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Zika Virus: Vaccine, Symptoms, Contagious, Treatment & Risks During Pregnant

Things to know about Zika virus

Picture of an Aedes aegypti mosquito, a vector that transmits the Zika virus; Photo by James Gathany

  • Zika virus is a virus related to dengue, West Nile, and other viruses.
  • Zika virus may play a role in developing congenital microcephaly (small head and brain) in the fetus of infected pregnant women.
  • The viral disease was first noted in 1947 in Africa and has spread by outbreaks to many different countries, with an ongoing outbreak in Brazil and Puerto Rico; the first diagnosis of the Zika virus in the U.S. occurred in Harris County (Houston), Texas, in January 2016.
  • The virus is transmitted to most people by a mosquito (Aedes) vector; the risk factor for infection is a mosquito bite.
  • The Zika virus’ incubation period is about three to 12 days after the bite of an infected mosquito.
  • The vast majority of infections are not contagious from person to person; however, they may be passed from person to person during sex.
  • The Zika virus symptoms and signs are usually
    • fever,
    • rash,
    • joint pain, and
    • conjunctivitis.
  • The virus infection is usually diagnosed by the patient’s history and physical exam and by blood testing (testing for the virus genome; usually done in the United States by the Centers for Disease Control and Prevention [CDC]).
  • Treatment is related to symptom control, and over-the-counter medication is used in most infected people.
  • Rarely, complications such as dehydration or neurologic problems may develop.
  • In Brazil, an outbreak of Zika virus infections may be related to the development of congenital microcephaly; evidence comes from epidemiology and Zika viruses isolated from amniotic fluid and the brain and heart of an infant with microcephaly.
  • The prognosis for most Zika virus infections is good; however, complications such as microcephaly, if proven to be related to the infection in pregnancy, would be a poor outcome for the newborn. In addition, eye abnormalities, Guillain-Barré syndrome, and acute disseminated encephalomyelitis (ADEM) may occur, with fair to poor outcomes.
  • Prevention of Zika virus infections is possible if mosquito bites from infected mosquitoes are prevented.
  • Currently, there is no vaccine against Zika virus infection; however, the possible link to the development of microcephaly in the fetus has prompted physicians to lobby for the fast development of a vaccine.

Zika Virus, Pregnancy & Microcephaly

Microcephaly may be caused by genetic abnormalities or by drugs, alcohol, certain viruses, and toxins that are exposed to the fetus during pregnancy and damage the developing brain tissue. Unfortunately, a 2015-2016 outbreak of Zika virus in Brazil has been associated with a large number of infants born with microcephaly. Epidemiological and some viral isolations suggest that pregnant women who get Zika virus have a high chance of fetal infection that may lead to microcephaly, although a definitive link between Zika virus infection and microcephaly is not yet proven.

What is Zika virus?

The CDC reported that researchers now conclude from new data published in the New England Journal of Medicine in April 2016, that the Zika virus is responsible for (causes) microcephaly and other serious brain defects.

Zika virus (sometimes termed Zika fever) is a Flavivirus that is related to dengue, West Nile, yellow fever, and Japanese encephalitis viruses (Flaviviridae); the viruses are transmitted to humans by mosquito bites and produce a disease that lasts a few days to a week. Common symptoms include fever, rash, joint pain, and conjunctivitis (redness of the eyes). In Brazil, the viral infection has been linked to birth defects (mainly small head and small brain size, termed microcephaly) in babies (newborns) whose mothers became infected with the Zika virus during their pregnancy. The CDC reported that researchers now conclude from new data published in the New England Journal of Medicine in April 2016, that the Zika virus is responsible for (causes) microcephaly and other serious brain defects. According to CDC Director Dr. Tom Frieden and other experts, these findings should serve as a warning to the U.S. to take Zika virus infections very seriously.

The WHO (World Health Organization) declared Zika virus infections as a public-health emergency in February 2016, after the Zika virus had been reported transmitted to humans in 62 countries worldwide.


Zika Virus Baby, Symptoms, Vaccine, Treatments
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What is the history of Zika virus outbreaks?

Zika virus (ZIKV) was first isolated and identified in the Zika Forest of Uganda in 1947. Studies suggest that humans in that area of Africa could also have been infected with the virus. From 1951 to 1981, blood tests showed evidence of Zika virus infections in many other African countries and Indonesia (Tanzania, Egypt, Sierra Leone, Malaysia, Thailand, and the Philippines, for example), and researchers found that transmission of the virus to humans was done by mosquitoes (Aedes aegypti). In 2007, the virus was detected on Yap Island, the first report was that the virus spread outside of Africa and Indonesia to Pacific Islands. The virus has continued to spread to North, Central, and South America (Mexico, Columbia, Brazil, and the Caribbean islands from Aruba to Jamaica). The most recent outbreaks have been noted in Puerto Rico, Cape Verde Islands, and a large ongoing outbreak is occurring in Brazil that started in May 2015 and is ongoing. The first isolation of the Zika virus in the U.S. occurred in January 2016 in Harris County (Houston), Texas, from an individual who became infected in El Salvador in November and returned to Texas. Although there have not been documented mosquito transmissions in the U.S., Texas and other states have two mosquito strains (Aedes aegypti and Aedes albopictus) that could be capable of transmitting the viruses (see maps below). The CDC also reports 354 individuals who had locally acquired infection (acquired through mosquito bites) in the U.S. territories (Puerto Rico and the U.S. Virgin Islands) and 346 travel-associated infections in the U.S. as of Apr. 6, 2016, but none due to mosquito bites in the U.S. The CDC expects these numbers to steadily increase.

For a map of the world where Zika virus infections occur, see the CDC world map at

Latest Infectious Disease News

What are causes and risk factors of a Zika virus infection?

Picture of a CDC map of the estimated range of Aedes aegypti in the U.S. in 2016; SOURCE: CDC.

Zika viruses are the cause of the infection. The viruses are transmitted to humans by infected vectors (Aedes mosquitoes) that also transmit other similar diseases such as dengue and Chikungunya. Theoretically, the viruses may be transmitted through blood transfusions or organ donations, although to date there are no reports of this type of transmission; there are numerous reports of Zika transmission through sexual contact.

The major risk factors to get the infection are being in areas where infected mosquitoes reside, having unprotected sex with a person who has recently been diagnosed with Zika, and not taking precautions to prevent mosquito bites. The following U.S. maps provided by the CDC shows where the two mosquito species that are capable of transmitting Zika viruses reside.


Zika Virus (Zika Fever)
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Is the Zika virus contagious?

Picture of a CDC map of the estimated range of Aedes albopictus in the U.S. in 2016; SOURCE: CDC.

Initially, in most outbreaks, the virus requires a mosquito vector to pass the virus to humans. Theoretically, donated blood and organ transplantation can allow rare person-to-person transmission. However, once a person gets a Zika infection, the virus can be contagious from that person to another person — under certain conditions, by sexual contact. Transmission of Zika viruses to sexual contacts occurs more frequently than previously suspected; research is ongoing.

How is the Zika virus transmitted?

The virus is mainly transmitted by infected mosquitoes that act as vectors to infect individuals during a mosquito bite. However, the virus can be transmitted from person to person once an individual becomes infected. Investigators have evidence that the transfer of the Zika virus is transmitted by sexual contact more frequently than first suspected, thus providing another way the virus is transmitted. Because the sexual transfer of this virus may be more frequent, physicians are recommending the use of condoms to protect uninfected sex partners from getting the disease.

Transmission could also happen in some other instances (blood transfusions, organ transplants, and from mother to fetus).

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What is the incubation period for a Zika virus infection?

The incubation period for Zika viruses is about three to 12 days after the mosquito bite. Symptoms may last about four to seven days. Approximately 60%-80% of infections do not produce any symptoms or signs. The incubation period for the virus infection transmitted by sexual contact is under investigation.

What is the contagious period for a Zika virus infection?

Zika virus can remain in semen (up to 93 days) longer than in other body fluids such as vaginal fluids, urine, or blood. The contagious period is not completely defined for Zika; however, the CDC recommends the following for individuals:

  • Non-pregnant couples: If the female is diagnosed with Zika, use barrier methods (condoms) or abstinence (abstaining from sex) for at least eight weeks after illness.
  • Non-pregnant couples: If the male is diagnosed with Zika, use barrier methods (condoms) or abstinence (abstaining from sex) for at least six months.
  • Pregnant couples: If either partner is infected, use barrier methods (condoms) or abstinence (abstaining from sex) until the pregnancy ends.

CDC experts state that over time they expect to have more precise information about Zika infections.


What exams and tests do health-care professionals use to diagnose a Zika
virus infection?

Health-care professionals will start diagnosis with a history and physical exam; patients should tell the provider about any recent travel to areas where the virus is active. If Zika virus infection is suspected, blood tests (done at the CDC with virus reverse transcriptase-polymerase chain reaction tests or RT-PCR) are likely to be ordered to detect the viruses and to differentiate between similar infections such as dengue fever or Chikungunya virus infections.

Can people who have returned from a country with active Zika outbreaks get tested for the infection?

Yes, it is possible to get tested for Zika. However, blood tests are not commonly done in many U.S. laboratories, so if your doctor agrees that you need such a test, the blood will be sent off to a specialty laboratory. The situation may change in the near future since laboratories may need to start testing for the viruses before releasing donated blood.

What is the treatment for a Zika virus infection?

There is no specific medicine that can treat the viral infection; the treatment is aimed at reducing the symptoms of the disease. Oral and/or IV hydration helps reduce symptoms and dehydration. The CDC has published highly detailed guidelines about Zika infections and treatment. However, they are too detailed (for example, see references 2 [6 pages] and 3 [90 slides]) to present in this article. In addition, the CDC is likely to modify these guidelines as data emerge from new studies of this virus. Pregnant women, in addition to receiving the symptomatic treatment described above, need to discuss assessments and treatments in detail with their OB/GYN doctor; each pregnant patient may need individualized treatment during pregnancy. The CDC provides an up-to-date podcast for pregnant women concerning the Zika virus (

What specialists treat Zika infections?

  • Many infected people do not require treatment or can be treated by their primary-care doctor, including family medicine specialists or internists.
  • With complications, OB/GYN doctors, maternal/fetal specialists, pediatric intensive-care specialists, and neurologists may be involved with the patient.
  • In addition, infectious-disease specialists and travel-medicine specialists may be consulted about Zika infections.

What are the complications of Zika virus infections?

Although complications of the virus infection are rare, some can be life-threatening, such as severe dehydration.

  • Neurological changes can occur; for example, Guillain-Barré syndrome.
  • In addition, a large increase in congenital malformations (mainly microcephaly) and other developmental issues have been associated with these viral infections in Brazil and are currently under study.
  • New studies suggest that eye abnormalities in microcephalic babies are linked to the virus infection (see the following section).
  • In addition, the infection may be the cause of another brain problem, acute disseminated encephalomyelitis (ADEM), in which the brain cells’ protective sheaths of myelin are disrupted, leading to symptoms like those of multiple sclerosis (MS).

What are the risks of contracting a Zika virus infection during pregnancy?

The risk to the mother of contracting a Zika virus infection during pregnancy is the same risk for individuals who are not pregnant, but the risk to the fetus to develop an abnormality such as microcephaly (small head and small brain) seems to be elevated in pregnancy, especially in Brazil. The epidemiological data and new research findings in Brazil suggest a likely association between congenital microcephaly and Zika infection in pregnant women. Zika virus infections first arose in Brazil in May 2015. Pregnant women, especially those in the first and early second trimester, in areas where the disease is prevalent should try to avoid any mosquito bites. Officials in Brazil are concerned since almost 4,000 babies (a very unusually high number as compared to similar time periods in which only about 150 babies were diagnosed with microcephaly) have been born with microcephaly since May 2015. In addition, Dr. R. Coeli, a pediatrician in Brazil, has reported Zika viruses isolated from the amniotic fluid of two women and one infant’s brain and heart tissue — results she concludes tie the Zika virus to microcephaly development. Officials have taken the unusual step to recommend women avoid pregnancy until the cause of the increase in microcephaly is definitively determined. Several agencies are intensively studying this problem, and a new study has data that researchers state definitively proves that the Zika virus causes microcephaly (see reference 3).

In addition, a new study of infants with microcephaly and presumed Zika virus congenital infection demonstrated that 10 of 29 infants studied (34.5%) had developed a range of vision defects from minor to vision-threatening lesions (focal pigment mottling, chorioretinal atrophy, and/or optic disc abnormalities). The researchers indicate there is no definitive link yet between the eye abnormalities and the virus infection, but if other diseases are ruled out, the investigators suggest the Zika virus maybe is linked to the development of these vision abnormalities. In a similar small study in Brazil, two people with Zika infection developed acute disseminated encephalomyelitis (ADEM) with brain cell damage to their brain’s white matter.

What is the prognosis of a Zika virus infection?

For the large majority of patients who get the viral infection, the prognosis is excellent with few or no complications developing. However, depending upon the association between the infection and congenital microcephaly, eye abnormalities, and Guillain-Barré syndrome being a cause-and-effect situation, the outcome of microcephaly is poor. Patients with ADEM may recover in about six months.

Is it possible to prevent a Zika virus infection?

Yes, it is possible to prevent Zika virus infections; this may be done by preventing any mosquito bites as the mosquitoes are the vector for the viral disease. In fact, some governments like those in Jamaica are encouraging residents to prevent infections by avoiding areas where mosquitoes breed, destroying areas where mosquitoes breed (for example, getting rid of old tires that contain water), wearing clothing that covers most of the skin areas of the body (long-sleeved shirts and pants), and by using mosquito repellents, such as DEET, oil of lemon eucalyptus, para-methane-diol, or permethrin (all are EPA-registered insect repellents).

Unfortunately, the two Aedes species of mosquitoes feed during the day, not only at dusk and at dawn; this increases the chances of a person getting a mosquito bite. Consequently, staying inside, removing standing water around the home, use of appropriate insect repellent, mosquito bed nets, and public-service spraying can help prevent Zika virus infections.

In addition, the CDC has recommendations for travel areas to avoid where the Zika virus is present in the mosquito population (see CDC travel recommendations below).

Is there a vaccine against Zika virus?

Currently, there is no vaccine to prevent Zika virus infections. The U.S. president and health officials are requesting emergency funding ($1.9 billion) to combat the Zika virus in the U.S. to help protect pregnant women and their fetuses from the disease, to develop a vaccine, and to reduce or eliminate Zika virus infections transmitted by mosquitoes. CDC officials are concerned that the problems such as neurological changes and microcephaly may be underestimated and the situation is “scarier than we initially thought,” according to Dr. Anne Schuchat, deputy director at the CDC.

CDC advisory on travel to areas with Zika virus, including the U.S. (Florida)

On Jan. 15, 2016, the CDC issued a travel alert concerning the Zika virus. The CDC recommended that pregnant women avoid traveling to areas with Zika outbreaks, and women thinking about becoming pregnant need to consult with their doctors before traveling to areas with Zika virus outbreaks. Women who must travel to areas with Zika virus outbreaks should consult with their doctors about pregnancy risks and take precautions to avoid any mosquito bites. The CDC is continually updating the world map of the locations where Zika virus outbreaks have and are occurring ( Some athletes have chosen to skip the Olympic Games scheduled in Brazil in 2016 because of the widespread Zika outbreak in the country.

In addition, the CDC has updated recommendations for travel areas to avoid where the Zika virus is present in the mosquito population so there is active transmission of the disease. This large list of countries can be found at the following site,, and now includes a neighborhood named Wynwood, in Miami, Florida. About 17 individuals have been infected with the virus by mosquito bites in this area. Public-health officials are actively trying to reduce or eliminate mosquito populations in Wynwood. However, CDC officials project there will be other neighborhoods or regions in the U.S. where mosquito populations will likely become infected with the virus and become vectors for the disease.

Medically Reviewed on 4/8/2022


Freitas, B., et al. “Ocular findings in infants with microcephaly associated with presumed Zika virus congenital infection in Salvador, Brazil.” JAMA Ophthalmol Feb. 9, 2016.

Goodman, Brenda. “CDC: Zika Virus Definitely Causes Microcephaly.” Apr. 13, 2016. .

Kelly, Janis C. “First Zika Virus Case in Continental United States Confirmed in Texas.” Jan. 11, 2016. .

Sweden. European Centre for Disease Prevention and Control. “Rapid Risk Assessment: Microcephaly in Brazil
Potentially Linked to the Zika Virus Epidemic.” Nov. 24, 2015. .

Sweden. European Centre for Disease Prevention and Control. “Zika Virus Infection.” Nov. 27, 2015.

United States. Centers for Disease Control and Prevention. “Update: Interim Guidelines for Health Care Providers Caring for Infants and Children with Possible Zika Virus Infection — United States, February 2016.” MMWR 65.7 Feb. 26, 2016: 182-187.

United States. Centers for Disease Control and Prevention. “Update on Interim Zika Virus Clinical Guidance
and Recommendations.” Jan. 26, 2016.

United States. Centers for Disease Control and Prevention. “Zika Virus.” Aug. 4, 2016. .

United States. Centers for Disease Control and Prevention. “Zika Virus: Areas With Zika.” Apr. 4, 2016.

United States. Centers for Disease Control and Prevention. “Zika Virus Disease in the United States, 2015-2016.” Feb. 11, 2016. .

Yaws Definition, Symptoms, Diagnosis, Treatment & Prevention

Yaws is an infectious disease that mainly occurs in the tropical areas of South and Central America, Asia, Africa, and the Pacific Islands. The disease is caused by a bacterium called Treponema pertenue, which causes lesions that look like bumps on the skin of the feet, hands, face, and genital area. Yaws is treated with penicillin or another antibiotic.

Yaws is a common chronic infectious disease that occurs mainly in warm humid regions such as the tropical areas of Africa, Asia, South and Central Americas, plus the Pacific Islands. The disease has many names (for example, pian, parangi, paru, frambesia tropica). Yaws usually features lesions that appear as bumps on the skin of the face, hands, feet, and genital area. 

Almost all cases of yaws begin in children under 15 years of age, with the peak incidence in 6- to 10-year-old children. The incidence is about the same in males and females. Yaws is a member of the treponematoses, which are diseases caused by spiral bacteria in the genus Treponema.

Besides yaws, the disease includes endemic syphilis (bejel) and pinta. Of these three diseases, yaws is the most common.

What are the symptoms of yaws?

  • Yaws most often starts as a single lesion that becomes slightly elevated, develops a crust that is shed, leaving a base that resembles the texture of a raspberry or strawberry.
  • This primary lesion is termed the mother yaw (also termed buba, buba madre, or primary frambesioma). Secondary lesions, termed daughter yaws, develop in about six to 16 weeks after the primary lesion.

Yaws Sign

Bumps on the Skin

Infections, tumors, and the body’s response to trauma or injury can all lead to lumps or bumps that appear to be located on or underneath the skin.

Depending upon the cause, skin lumps or bumps may vary in size and be firm or soft to the touch. The overlying skin may be reddened or ulcerated. Skin bumps may or may not be painful or tender, depending upon the cause of the lesions.

What causes yaws?

  • Yaws is caused by a particular bacterium called a spirochete (a spiral-shaped type of bacteria). The bacterium is scientifically referred to as Treponema pertenue. This organism is considered by some investigators to be a subspecies of T. pallidum, the organism that causes syphilis (a systemic sexually-transmitted disease).
  • Other investigators consider it to be a closely related but separate species of Treponema. T. carateum, the cause of pinta (a skin infection with bluish-black spots), is also closely related to T. pertenue.
  • The history of yaws is unclear; the first possible mention of the disease is considered to be in the Old Testament. D. Bruce and D. Nabarro discovered the spirochete causing yaws (T. pertenue) in 1905.

What are risk factors for yaws?

  • The main risk factor for yaws is direct contact with another person (nonsexual contact) that has yaws lesions on the skin or being a member of the community where yaws infections are endemic.
  • The bacteria that cause yaws only infect humans if there is a break (cut) or abrasion of the skin.
  • Consequently, having a break (cut) or abrasion of the skin while in a geographic area where yaws is endemic is another risk factor for yaws.
  • Poor hygiene and crowded conditions are also risk factors.

How does yaws begin and spread?

  • Yaws begins when T. pertenue penetrates the skin at a site where skin was scraped, cut, or otherwise compromised. In most cases, T. pertenue is transmitted from person to person.
  • At the entrance site, a painless small lesion, or bump, arises within two to eight weeks and grows. The initial lesion is referred to as the mother yaw.
  • The lymph nodes in the area of the mother yaw are often swollen (regional lymphadenopathy). When the mother yaw heals, a light-colored scar remains.


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Why is this disease called yaws?

  • The term yaws is thought to be of Caribbean origin. In the language of the Carib Indian people, yaya is the word for “a sore.”
  • Alternatively, the disease term yaws may have come from Africa where the word yaw may have meant “a berry.”
  • Because the lesions of yaws look like berries, the disease is also called frambesia (or frambesia tropica) from the French framboise, meaning “raspberry.”
  • Other older names for yaws include granuloma tropicum, polypapilloma tropicum, and thymiosis.

What are developmental stages in the course of yaws?

  • Yaws has four stages: primary, secondary, latent, and tertiary.
  • The primary stage is the appearance of the mother yaw. Patients with yaws develop recurring (“secondary”) lesions and more swollen lymph nodes. This represents the secondary stage.
  • These secondary lesions with rashes may be painless like the mother yaw or they may be filled with pus, burst, and form ulcers. The affected child often experiences malaise (feels poorly) and anorexia (loss of appetite).
  • The latent stage occurs when the disease symptoms abate, although an occasional lesion may occur.
  • In the tertiary stage, yaws can destroy areas of the skin, bones, and joints and deform them with pains in the joints and/or bones. The palms of the hands and soles of the feet tend to become thickened and painful (crab yaws).

What types of specialists treat yaws?

  • Usually, clinics or traveling doctors treat yaws because the populations that get the disease are usually the poor who have no medical care.
  • However, specialists like infectious-disease doctors, travel-medicine specialists, rheumatologists, dermatologists and others, depending on the extent of the disease, may be consulted if the patient is treated in more modern facilities.

Latest Infectious Disease News

How is yaws diagnosed?

  • Yaws is suspected in any child who has the characteristic clinical features and lives in an area where the disease is common. With increasing travel, a child once in the tropics may carry the disease to a more temperate area of the world.
  • Laboratory confirmation of the diagnosis is by blood serum tests (for example, RPR or rapid plasma reagent test, VDRL test or venereal disease research laboratory test, TPHA or Treponema pallidum hemagglutination test, FTA-ABS or fluorescent treponema antibody absorption), but most frequently the diagnosis is made on clinical findings.
  • The reason that T. pallidum serum tests are used is that the spirochetes are so closely related, they have similar antigens on their surfaces so that T. pallidum and T. pertenue are cross-reactive (detected by the same serological tests). Special (dark-field) examination under the microscope in which technicians can actually see the spirochete bacterium is also used to help diagnose yaws.
  • The lesions (both the mother yaw and the secondary lesions) usually have many T. pertenue organisms that can be visualized with dark-field examination of lesion scrapings.
  • On a typical Gram stain (a procedure for identifying bacteria when viewed microscopically), the organisms are considered to be Gram-negative but stain so poorly and are so small and thin, the Gram stain often does not reveal the organisms; hence the use of the dark-field examination.
  • Other tests that detect spirochetes such as a silver stain or electron microscopy are used mainly by research scientists. PCR tests can confirm yaws by detecting genetic material from organisms in samples from skin lesions.

What is the treatment for yaws?

  • Treatment of yaws is simple and highly effective. Penicillin G benzathine given IM (intramuscularly) can cure the disease in the primary, secondary, and usually in the latent phase.
  • Penicillin V can be given orally for about seven to 10 days, but this route is less reliable than direct injection. Anyone allergic to penicillin can be treated with another antibiotic, usually erythromycin, doxycycline, or tetracycline.
  • Azithromycin (in a single oral dose of 30 mg/kg or the maximum 2 g) is the choice that the World Health Organization (WHO) recommends because of the ease of administration.
  • Tertiary yaws, which occurs in about 10% of untreated patients five to 10 years after initially getting the disease, is not contagious. The tertiary yaws patient is treated for the symptoms of the chronic conditions (altered or destroyed areas in bones, joints, cartilage, and soft tissues) that develop as complications of the infection.
  • There is no vaccine for yaws.


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Why is yaws a serious problem?

  • Yaws is a major public-health threat in the tropics. Tropical regions in Central and South America, Africa, Asia, and Oceania are all at continuing risk for yaws.
  • A high percentage of children in such areas can be infected. Transmission of the disease is facilitated by overcrowding and poor hygiene, and yaws tends to be more prevalent in poor areas. In addition to making young children sick, approximately 10% of untreated children develop into young adults with deformities that are severely debilitating in the tertiary-yaws phase. For example, some patients develop destructive ulcerations of the nasopharynx, palate and nose (termed gangosa), painful skeletal deformities, especially in the legs (termed saber shins), and other soft-tissue changes (gummas, inflammatory cell infiltration).
  • Yaws can be completely eradicated from an area by giving penicillin or other appropriate antibiotics to everyone in the population. This may, unfortunately, cost more than a poor country can afford.
  • From 1950-1970, a worldwide effort to eradicate yaws was begun and made progress in reducing the approximately 50 million worldwide cases; after its end, yaws has seen a resurgence.
  • In the 1990s, attempts to eliminate yaws started again, with limited success as the effort is not worldwide or coordinated but done by individual countries. The WHO (World Health Organization) in 2007 reported about 2.5 million cases worldwide but freely admits their data is faulty, as most countries do not calculate the prevalence of yaws.
  • WHO estimates that about 460,000 new cases of yaws occur each year.

What is the prognosis of yaws?

  • The prognosis of yaws depends upon effective treatment so that the patient will not develop complications.
  • If appropriate treatment of yaws takes place before tertiary yaws develops, the prognosis for a possible cure with little or no complications is good. However, if tertiary yaws develops, the prognosis is worsened depending upon the severity of complications.

Is it possible to prevent yaws?

  • There is no vaccine available to prevent yaws. However, the WHO has established a yaws eradication strategy also referred to as the Morges strategy by which the organization has established a goal of eradicating yaws by about 2020. Because this disease is spread by person-to-person transfer and has no animal reservoir, the WHO considers this a realistic goal.
  • Currently, for individuals, prevention is based on interrupting the transmission of the disease from person to person by practicing good hygiene and by early diagnosis and rapid appropriate treatment with azithromycin to prevent spread in the community.

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Medically Reviewed on 8/5/2021


Switzerland. World Health Organization. “Yaws.” June 2016. .

Yeast Infection vs. Diaper Rash Pictures, Treatment, Remedies

What are yeast infections and diaper rash in infants, babies, toddlers, and children?

A yeast diaper rash infection can be caused by many things.

Yeast infections are infections by fungi (yeast) predominantly of the genus Candida, species albicans that may, depending on the health of an individual’s immune system, cause superficial infections of mucocutaneous disease like thrush, to life-threatening invasive infections. 

Diaper rash is a term used to describe rashes that occur due to wearing a diaper (here confined to those worn by babies, infants, toddlers, and children up to about age 2. Peak incidence in diaper rash is ages 9-12 months.

What is the difference between a yeast infection and diaper rash?

Diaper rash lasting about 3 or more days may be caused by Candida in about 45%-75% of all diaper rashes in infants, babies, toddlers, and kids that wear diapers, and is considered Candidal diaper dermatitis or superficial mucocutaneous fungal infection. Consequently, a superficial yeast infection and diaper rash can be the same infection in many infants, babies, toddlers, and children.


How can you tell if it’s a yeast infection or diaper rash?

If yeast cells are seen microscopically in diaper rash skin samples or in cultures, the rash is likely due to the fungi; if fungi is not found or cultured, the diaper rash probably has another cause.


Is a Yeast Infection from Diaper Rash Contagious?

Most yeast infections are not contagious. Usually, infections occur when conditions on the skin, mouth (mucosal surface), vagina and penis/foreskin develop extra moisture and warmth, often associated with a suppressed immune system. It is in these situations where Candida can ideally grow and multiply.

Candida infections are the major cause of diaper rash in children. Most
commonly, yeast can cause infection of skin and mucous membranes. Such
infections are called mucocutaneous candidiasis, which occur mainly in warm, moist areas of the body where the skin is often folded together,
for example,

  • diaper rash in infants, babies, toddlers, and children.
  • the groin,
  • armpits,
  • underneath the breasts, and
  • occasionally, the fingernails.

Candida infection also can infect;

  • the mouth (oral thrush),
  • vagina (yeast vaginitis), and
  • infect or inflame of the male head of the penis and/or the foreskin (balanitis).

What are the differences in the symptoms and signs of a yeast infection vs. diaper rash?

If diaper rash is caused by yeast. There are no significant differences in the signs and symptoms of yeast infections and diaper rash; however, diaper rash caused by yeast is reddish and macerated skin that is painful when touched or rubbed against the diaper, and may extend past the diaper and include the genitals. About 75% of female babies/young girls may develop vaginal yeast infections (vulvovaginal candidiasis).

What are the differences in the causes of yeast infections and diaper rash?

The main cause of most yeast infections are fungi in the genus Candida. Although this genus causes about 45%-75% of all diaper rashes, some diaper rashes are caused by:

  • Skin overhydration
  • Skin maceration
  • Skin with prolonged contact with urine and feces
  • Diaper soaps
  • 3 or more diarrheal stools per day
  • Biotin deficiency
  • Contact dermatitis
  • Allergic reactions
  • What exams or tests diagnose yeast infections and diaper rash?

    Skin scrapings or biopsy material can be cultured or examined with a microscope after potassium hydroxide treatment that reveals the fungi, but is seldom used to diagnose diaper rash. Usually, observing a yeast infection and/or diaper rash is all that is needed. 


    Parenting Guide: Healthy Eating for Kids
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    What are the treatments for yeast infections and diaper rash?

    • Creams that contain zinc oxide are the first treatments for almost all diaper rash causes. 
    • If yeast are the causes of infection/diaper rash, antifungal treatment (for example, nystatin cream and
    • others) may be used.
    • One percent hydrocortisone cream may reduce discomfort and inflammation. 
    • There are many over-the-counter (OTC) antifungal medications, creams and ointments available.

    Check with your pediatrician for their recommendations.

    Can yeast infections or diaper rash be treated at home with natural remedies?

    • Changing diapers more often and keeping the diaper area clean and dry helps prevent all causes of diaper rash, including yeast. 
    • The chance of a yeast infection decreases when you allow some time for the child to be without a diaper, for example, lying the baby on a dry towel. 
    • Do not use diapers that fit too tightly against the skin. 
    • Over-the-counter home remedies are available, to treat yeast infections, for example, Desitin, A+D ointment, Triple Paste, and Vaseline for both prevention and treatment. 
    • Check with the child’s doctor before using any product on infants, babies, toddlers, and children for yeast infections and diaper rash. 
    • Severe diaper rash and/or yeast infections usually require additional treatments that may include systemic antifungals and even hospitalization.

    Can yeast infections or diaper rashes be dangerous to infants, babies, toddlers, and children?

    • In general, most diaper rashes caused by yeast are not dangerous. The exceptions are those individuals; who are immunocompromised because yeast may proliferate and become systemic. 
    • Severe yeast infections and/or diaper rash may lead to skin breaks that allow other organisms to infect the person.

    Can yeast infections and diaper rash be cured?

    Yes. Most yeast infections and diaper rash can be cured. However; bad or severe yeast infections in munocompromised individuals may be difficult to cure.


    Newborn babies don’t sleep very much.
    See Answer


    Agrawal, R, et al. Diaper Dermatitis (Diaper Rash). Medscape. Updated: Aug 23, 2019.

    Hidalgo, J, et al. Candidiasis. Medscape. Updated: Apr 4, 2019.

    Yeast Infection vs. Bacterial Vaginosis (BV): Similarities, Differences & Treatment

    What is a yeast infection? What is bacterial vaginosis?

    A yeast infection and bacterial vaginosis both cause vaginal discharge.

    A yeast infection is an infection with any type of yeast. In women, vaginal yeast infections are common. This article will focus on the similarities and differences between vaginal yeast infections and bacterial vaginosis (BV), another condition of the vagina that causes vaginal discharge.

    What the causes and risk factors of a yeast infection and bacterial vaginosis?

    A vaginal yeast infection usually occurs when the normal balance of yeast and bacteria in the vagina is altered, allowing excessive growth of the yeast. The yeast known as Candida is the main cause of vaginal yeast infections. Vaginal Candidiasis is another name for this infection. Suppression of immune function can increase the likelihood of developing yeast infections. Similarly, an abnormal overgrowth or imbalance of the bacteria that are normally present in the vagina cause bacterial vaginosis. BV is not a true infection but rather a disruption in the balance of normal bacteria. BV was formerly referred to as Gardnerella vaginitis, because people believed that Gardnerella bacteria were responsible for the condition.

    Risk factors for both BV and yeast infection can include recent antibiotic use. Other risk factors for a yeast infection include

    • high estrogen levels,
    • pregnancy,
    • uncontrolled diabetes, and
    • suppression of the immune system.

    A number of factors can increase a woman’s risk of BV, including

    • multiple or new sex partners,
    • IUD use,
    • vaginal douching, and
    • cigarette smoking.

    What are the signs and symptoms of yeast infections and bacterial vaginosis?

    BV often does not cause specific symptoms. When it does cause symptoms, both BV and yeast infections cause vaginal discharge. With a yeast infection, the discharge is white-gray, thick, and often having the consistency of cottage cheese. Other symptoms of yeast infections include

    • intense itching,
    • vaginal burning or irritation,
    • painful intercourse, and
    • pain or burning during urination.

    The discharge typically seen with BV is thinner and grayish-white in color. BV also can cause vaginal odor and sometimes pain or irritation.

    Yeast Infection Treatment

    Topical antibiotic (antifungal) treatments (applied directly to the affected area) are available without a prescription. These include vaginal creams, tablets, or suppositories. Regimens vary according to the length of treatment and are typically 1- or 3-day regimens. Recurrent infections may require even longer courses of topical treatment. These topical treatments relieve symptoms and eradicate evidence of the infection in up to 90% of those who complete treatment.

    What exams do doctors use to diagnose a yeast infection and bacterial vaginosis?

    Doctors diagnose both yeast infection and BV by examination of a sample of the vaginal discharge in the laboratory. There is also a whiff test for BV that involves testing the vaginal discharge with a chemical that produces a characteristic odor when BV is present.

    What are treatments and home remedies for yeast infections and bacterial vaginosis?

    There are no home remedies that can cure either a yeast infection or BV. Prescription and over-the-counter antifungals (for example, miconazole and fluconazole) are the most common treatments of yeast infections. Antibiotics (for example, metronidazole and clindamycin) are the treatment of choice for bacterial vaginosis conditions.

    What the prognosis of a yeast infection and bacterial vaginosis?

    Symptoms of both a BV and yeast infection typically resolve once appropriate treatment starts. In both cases, recurrence of the yeast infection or repeat bouts of BV are common. However, they typically do not produce long-term complications.

    Is it possible to prevent yeast infections and bacterial vaginosis?

    Careful attention to hygiene may help prevent some yeast infections, as well as changing out of wet bathing suits or damp clothes as soon as possible. Loose-fitting cotton underwear decreases moisture in the genital area and may help prevent yeast infections. Avoidance of vaginal douching can also help prevent both conditions. Reducing certain risk factors, such as limiting the number of sex partners and taking all medications as directed when being treated for bacterial vaginosis, can also help reduce a woman’s risk of developing bacterial vaginosis. However, it is not possible to completely prevent either condition.


    Bacterial Infections 101: Types, Symptoms, and Treatments
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    United States. Centers for Disease Control and Prevention. “Bacterial vaginosis.” .

    United States. Centers for Disease Control and Prevention. “Candidiasis.”

    Yeast Infection vs. Urinary Tract Infection (UTI): Similarities & Differences

    What is a yeast infection? What is a urinary tract infection (UTI)?

    Yeast infections and UTIs both cause painful urination.

    A yeast infection is an infection with any type of yeast, but
    people commonly use the term to refer to vaginal yeast infections in women. A yeast known as
    Candida albicans typically causes vaginal yeast infections. Vaginal yeast infections are also referred to as vaginal Candidiasis. In contrast, a urinary tract infection (UTI) is not an infection of the vagina but of the urinary tract (the lower urinary tract is made up of the urethra and bladder). Bacteria are the main cause of UTIs, and the most common bacterial cause of a UTI is
    E. coli.

    How do the causes and risk factors of a yeast infection differ from the causes of a UTI?

    UTIs occur when bacteria enter the urinary tract at the urethra. This can happen during sexual intercourse in women or due to improper wiping after a bowel movement. A vaginal yeast infection usually occurs when
    something alters the normal balance of yeast and bacteria in the vagina, allowing excessive growth of the yeast. Suppression of immune function can increase the likelihood of developing both UTIs and yeast infections. Antibiotic use, diabetes, and impaired immune systems are all possible causes of a yeast infection.

    Are UTIs and yeast infections contagious?

    It is possible for a woman to transmit a yeast infection to a male sex partner, even though yeast infection is not considered to be a sexually transmitted disease (STD). Yeast infections can occur in women who are not sexually active. UTIs are not contagious.

    What are the signs and symptoms of yeast infections and UTIs?

    The most common symptoms of a UTI include

    • pain with urination (dysuria),
    • frequent urination,
    • feeling an urgent need to urinate,
    • blood in the urine, and
    • cloudy urine or pus visible in the urine.

    A mild fever may be present. Yeast infections are characterized by

    • intense itching,
    • a thick white-gray vaginal discharge that may resemble cottage cheese,
    • vaginal burning or irritation,
    • painful intercourse, and
    • pain or burning during urination.

    Vaginal or vulvar swelling, redness, and soreness may be present.

    Symptom of UTI & Yeast Infection

    Painful Urination

    Burning urination or painful urination is also referred to as dysuria. A burning sensation with urination can be caused by infectious (including sexually transmitted infections, or STDs such as chlamydia and gonorrhea) and noninfectious conditions, but it is most commonly due to bacterial infection of the urinary tract affecting the bladder. It is often accompanied by other symptoms of urinary tract infections (UTI), such as dysuria (painful urination) or blood in the urine, and it can occur after intercourse in women when infection is present. Burning or painful urination during pregnancy is also suggestive of a urinary tract infection.

    What exams do doctors use to diagnose a yeast infection and a UTI?

    Urine tests diagnose a UTI. Abnormalities can appear on a dipstick urinalysis test that suggest a UTI is present. Sometimes
    medical professionals take a culture of the urine to determine the type of bacteria causing the infection.
    A physical exam and an examination of a sample of the vaginal discharge in the laboratory can confirm the presence of a yeast infection.

    What are treatments and home remedies for yeast infections and UTIs?

    There are no home remedies that can cure either a yeast infection or a UTI. Prescription antibiotics are required for the treatment of a UTI, and antifungal drugs are required for treatment of a yeast infection. Some antifungal drugs are available over the counter. Depending on the frequency and duration of yeast infections, your provider will choose different therapies and lengths of treatment.

    What is the prognosis and duration of a UTI compared to a yeast infection?

    Both a UTI and yeast infection should resolve rapidly once appropriate treatment has begun. With both conditions, repeat infections or recurrences are common, but long-term complications are very rare.

    Is it possible to prevent UTIs and yeast infections?

    Careful attention to hygiene may help prevent some UTIs. This includes always cleaning the genital area from front to back. This practice can also help prevent yeast infections, as well as changing out of wet bathing suits or damp clothes as soon as possible. Loose-fitting cotton underwear can help reduce moisture in the genital area and may help prevent yeast infections. Avoiding products with potential irritants like douches or scented tampons can also help prevent yeast infections. However, it is not possible to completely prevent either condition from developing.


    Urinary Incontinence in Women: Types, Causes, and Treatments for Bladder Control
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    Jameson, J. Larry, et al. Harrison’s Principles of Internal Medicine, 20th Ed. New York: McGraw-Hill Education, 2018.

    Yeast Infection vs. STDs Differences, Symptoms, Causes, Treatment

    What are STDs?

    Even men can get yeast infections from women.

    STDs, also termed sexually transmitted diseases, are infections that are mainly transmitted to others during direct sexual contact (genital, anal and/or oral); a few types may be contracted by nonsexual means like needle sticks (for example, hepatitis B, AIDS).

    What is a yeast infection?

    A yeast infection is the invasion and multiplication of a fungus (yeast) in or on the body. Yeast infections are not usually transmitted person to person and are not considered to be an STD. There are three types of yeast infections:  Vaginal candidiasis, Thrush (oral and esophagus) and Invasive. This article will emphasize the vaginal (genital) type vs STDs.

    What yeast infections feel like STDs?

    In women, a vaginal yeast infection may mimic STDs while in men, a yeast infection of the urethra and/or foreskin may feel like an STD.

    15 Signs and Symptoms of STDs in Women

    Common STDs (Sexually Transmitted Diseases) and Symptoms in Women

    Gonorrhea symptoms and signs include;

  • burning during urination,
  • frequent urination,
  • a yellowish vaginal discharge,
  • redness and swelling of the genitals, and
  • vaginal itching or burning.
  • Chlamydia symptoms and signs include;

  • abdominal pain
  • urethra infection,
  • urinary tract infections (UTIs), and
  • pelvic inflammatory disease (PID).
  • Syphilis symptoms and signs include;

  • ulcers or chancres
  • rash
  • hair loss,
  • sore throat,
  • fever, headaches,
  • white patches in the nose, mouth, or vagina.
  • How do you get a yeast infection or an STD?

    • Most yeast infections occur when yeast, (Candida albicans, mainly) that are normally present on the body, develop conditions that allow the yeast to proliferate and produce symptoms.
    • STDs are mainly transmitted person to person through sexual contact and occasionally by contaminated items like needles.


    What tests diagnose yeast infections and STDs?

    Tests to diagnose yeast infections include microscopic visualization of the yeast and/or culture of the fungi. However, blood tests or culture swabs for STDs are often done to prove or diagnose if an individual has an STD.


    Bacterial Infections 101: Types, Symptoms, and Treatments
    See Slideshow

    What is the treatment for yeast infections and STDs?

    • The treatment for yeast infections are usually over-the-counter (OTC) creams, ointments or suppositories containing antifungal medication like miconazole or fluconazole in women and mainly creams for men.
    • Treatment for STDs vary depending on the cause of the STD (for example, antivirals for some and antibiotics for other STDs).

    Can condoms protect against yeast infections and STDs?

    Because most yeast infections are not transmitted person to person, there is little evidence that a condom can protect against yeast infections. However, condoms have a good chance to prevent some STDs (estimated to be about 85-98% effective).

    How long does it take for yeast infections and STDs to heal and cure?

    • Mild yeast infections may clear in about 3 days.
    • More severe infections may take 1-2 weeks.
    • Almost all yeast infections can be cured. In contrast, STDs time of infection and cure potential vary widely; some, depending on the cause, may last a lifetime and never be cured.

    Are there home kits to test for a yeast infection or STD?

    There are home kits to test for yeast infection (for example, Monistat Vaginal Health Test). Also, there are separate STD test kits for men and women that claim to be able to detect seven common STDs (for example, Everlywell STD for men). 

    Latest Sexual Health News

    Are there free or pay for clinics to get tested for yeast infections and STDs?

    • Free clinics in your area that can test or diagnose yeast vs STDs infections may be located by contacting your local Community Health Center or simply by going to the internet and searching for free clinics in your area.
    • Almost all pay clinics and urgent care centers can test you for yeast infections and STDs.



    Bowel regularity means a bowel movement every day.
    See Answer


    Agrawal, R, et al. Diaper Dermatitis (Diaper Rash). Medscape. Aug 23, 2019.

    Hidalgo, J, et al. Candidiasis. Medscape. Apr 8, 2019.

    Yellow Fever Symptoms, Vaccine, Treatment & History

    Yellow fever facts

    • Yellow fever is an infectious disease caused by the yellow fever virus.
    • Yellow fever is a vector-borne disease transmitted to humans by the bite of infected mosquitoes.
    • Yellow fever is endemic in areas of Africa and South America.
    • The symptoms of yellow fever include fever, headache, and muscle aches, with some patients going on to develop life-threatening complications.
    • Health care professionals diagnose yellow fever clinically, with laboratory confirmatory testing available.
    • The treatment for yellow fever is supportive.
    • It is possible to prevent yellow fever with vaccination and mosquito-control measures.

    What is yellow fever? What is the history of yellow fever?

    Yellow fever is an acute viral infectious disease transmitted to humans through the bite of infected mosquitoes. Though many cases of yellow fever are mild and self-limiting, yellow fever can also be a life-threatening disease causing hemorrhagic fever and hepatitis (hence the term “yellow” from the jaundice it can cause). This viral disease occurs in tropical areas of Africa and South America, and each year there are an estimated 200,000 cases of yellow fever worldwide, leading to approximately 30,000 deaths. An increase in the number of cases of yellow fever in the last few decades has led to campaigns aimed at improving public awareness and disease prevention for this re-emerging infectious disease.

    Several significant yellow fever outbreaks have occurred throughout history, with the first documented outbreak occurring in the Yucatan peninsula during the 17th century. During the late 18th century, a severe yellow fever outbreak struck New England and several North American port cities. The city of Philadelphia lost about one-tenth of its population during the 1793 yellow fever epidemic, causing many notable figures in American politics to flee the city. The last major yellow fever outbreak in North America occurred in New Orleans in 1905.

    In the late 19th century, Dr. Carlos Finlay, a Cuban physician, first proposed the theory that a mosquito transmits yellow fever. It was not until 1900, using earlier research from Dr. Finlay as a foundation, that U.S. Army Major Dr. Walter Reed and his team proved that mosquitoes, in fact, transmit yellow fever. This groundbreaking idea was instrumental in leading to the subsequent control of yellow fever in various regions. The virus responsible for yellow fever was later isolated in the late 1920s, and this breakthrough discovery later allowed Max Theiler to develop the first vaccine against yellow fever in the 1930s. This successful vaccine helped control and eliminate yellow fever from various countries in Africa and South America during the mid-20th century.

    Unfortunately, yellow fever has had a large outbreak of the disease that began in 2017 and has spread to several Brazilian states. In addition, some unvaccinated travelers became infected and several died. The CDC recommends travelers (age 9 months and older) are vaccinated against the disease at least 10 days before arriving in Brazil. Those people who are unvaccinated and traveling in Brazil should avoid areas where vaccination is recommended (see map below from CDC; most areas of Brazil are included).

    This picture shows multiple virions of the yellow fever virus. Source: CDC

    Yellow Fever Vaccination

    Do you need vaccinations before traveling abroad?

    Travelers to other countries often face health issues
    they wouldn’t ordinarily experience at home. To minimize your risks of becoming
    seriously ill when traveling abroad, you should find out in advance whether any
    specific immunizations may be recommended for travel to the region of the world
    you’ll be visiting. It’s also a good time to review your own immunization

    What causes yellow fever?

    A virus causes yellow fever. The yellow fever virus is a single-stranded RNA virus that belongs to the Flavivirus genus. After transmission of the virus occurs, it replicates in regional lymph nodes and subsequently spreads via the bloodstream. This widespread dissemination can affect the bone marrow, spleen, lymph nodes, kidneys, and liver, in addition to other organs. Tissue damage to the liver, for example, can lead to jaundice and disrupt the body’s blood-clotting mechanism, leading to the hemorrhagic complications sometimes seen with yellow fever.

    How do people contract yellow fever?

    The bite of infected mosquitoes transmits yellow fever to humans. Various species of Aedes and Haemagogus mosquitoes serve as vectors and are responsible for the transmission to human and nonhuman primates, which serve as reservoirs for the disease. There are three transmission cycles for yellow fever.

    • Sylvatic (jungle) cycle: In tropical rainforests, infected monkeys pass the virus to mosquitoes that feed on them. These infected mosquitoes then bite humans who enter the rainforest for occupational (for example, loggers) or recreational activities.
    • Intermediate (savannah) cycle: In humid or semi-humid regions of Africa, mosquitoes that breed around households and in the wild (semi-domestic mosquitoes) infect both humans and monkeys. The virus can be transmitted from monkeys to humans, or from human to human by the mosquitoes. This is the most common type of outbreak in Africa.
    • Urban cycle: When infected humans introduce the virus into urban areas with large numbers of unvaccinated individuals, infected mosquitoes (Aedes aegypti) transmit the disease from human to human. This form of transmission can lead to large epidemics.

    This picture shows a female Aedes aegypti mosquito. Source: CDC


    Yellow Fever
    See pictures of Bacterial Skin Conditions
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    What areas are high risk for contracting yellow fever?

    Yellow fever is endemic in tropical and subtropical regions of both Africa and South America, though an estimated 90% of the worldwide reported infections occur in Africa. Most of the infections on the African continent occur in unvaccinated individuals who inhabit the sub-Saharan region. In Asia, there have been no cases of yellow fever outbreaks. However, this area remains a theoretical risk because the mosquitoes responsible for transmission, as well as the susceptible primates, are there.

    Countries where yellow fever is presentSource: CDCAngolaGuyanaArgentinaKenyaBeninLiberiaBoliviaMaliBrazilMauritaniaBurkina FasoNigerBurundiNigeriaCameroonPanamaCentral African RepublicParaguayChadPeruCongoRwandaCongo, DRCSao Tome & PrincipeColombiaSenegalCote d’Ivoire (Ivory Coast)Sierra LeoneEcuadorSomaliaEquatorial GuineaSudanEthiopiaSurinameFrench GuianaTanzaniaThe GambiaTrinidad & TobagoGabonTogoGhanaUgandaGuineaVenezuelaGuinea-BissauZambia

    Several factors determine an individual’s risk of acquiring yellow fever during travel, including the area of travel, season, immunization status, duration of exposure, activities during travel, and the local rate of virus transmission. Review this information before any travel to endemic areas. Below is a map of areas of risk for yellow fever in Africa (CDC map, 2018).

    Picture of countries with risk of yellow fever virus transmission; Source: CDC

    Latest Infectious Disease News

    What is the incubation period for yellow fever?

    The period from contracting the infection to the development of symptoms (incubation period) is generally between three to six days.

    Is yellow fever contagious? How long is the contagious period for yellow

    The bite of infected mosquitoes (for example, Haemagogus leucocelaenus and/or Aedes serratus mosquitoes) transmits yellow fever to humans. Direct contact with other infected individuals does not transmit yellow fever. Humans with yellow fever are infectious and can transmit the virus to uninfected mosquitoes shortly before the onset of fever and for three to five days after the onset of symptoms.

    What types of specialists treat yellow fever?

    A variety of specialists may become involved in the care of patients who develop symptoms of yellow fever. Initially, primary care physicians, including family physicians, internists, emergency physicians, and pediatricians, may encounter patients with yellow fever. Infectious-disease specialists care for individuals diagnosed with yellow fever, as well. Patients with yellow fever may see other specialists depending on the severity of their illness and the development of complications (for example, a nephrologist in cases of kidney failure).

    What are yellow fever symptoms and signs?

    After infection with the yellow fever virus, many individuals will experience no clinically apparent manifestations of the mosquito-borne disease (asymptomatic), while others will go on to develop a mild, self-limiting flu-like illness characterized by the following symptoms and signs:

    • Fever
    • Chills
    • Generalized muscle pain
    • Back pain
    • Headache
    • Malaise
    • Weakness
    • Lack of appetite
    • Nausea
    • Vomiting

    Most patients with this initial acute phase of the disease improve spontaneously after approximately three to four days. However, approximately 15% of patients may enter a second phase of the disease that typically appears after a short remission of symptoms (about 24 hours) from the initial phase of the illness. This next toxic phase of the disease is more severe, at which time the high fever returns and more organ systems become involved. In addition to the above symptoms, the following symptoms and signs may also develop:

    • Abdominal pain
    • Jaundice
    • Bleeding from the gums, nose, eyes, and/or stomach
    • Blood in the stool and blood in the vomit
    • Easy bruising of the skin
    • Kidney failure
    • Confusion
    • Seizures
    • Coma


    Infectious Disease: Are These Historical Illnesses Coming Back?
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    How do health care professionals diagnose yellow fever?

    Because the symptoms during the initial phase of yellow fever are nonspecific and similar to a flu-like illness, diagnosis during this stage can be difficult. Therefore, health care professionals make a preliminary clinical diagnosis based on the patient’s signs and symptoms, the travel history (when and where), the related travel activities, and vaccine history.

    Various blood test abnormalities may be present in individuals with yellow fever, particularly those who go on to develop the second toxic phase of the disease. Blood test abnormalities may include a low white blood cell count (leukopenia), a low platelet count (thrombocytopenia), elevations in liver function tests, abnormally prolonged blood clotting times, and abnormal electrolyte and kidney function tests. None of these test results is specific to yellow fever and alone allow the health care provider to make a diagnosis. Urine tests may demonstrate elevated levels of urinary protein and urobilinogen. An electrocardiogram (ECG) may reveal heart conduction or rhythm disturbances if cardiac involvement has occurred.

    The laboratory diagnosis of yellow fever requires specialized testing. Blood tests may demonstrate the presence of virus-specific antibodies (IgM and IgG) produced by the immune system in response to the infection, though cross-reactivity with antibodies from other flaviviruses may occur. Therefore, specific antibody testing, such as a plaque reduction neutralization test, may be done for confirmation of yellow fever virus versus others like Zika virus.

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    What is the treatment for yellow fever?

    There is no specific curative treatment for yellow fever. Treatment is supportive and aimed at relieving the symptoms of the disease, including the pain and fever. As previously mentioned, the majority of patients who do develop symptoms from yellow fever will experience a mild course of illness that will resolve on its own.

    Supportive measures implemented depend on the severity of the disease, and may include

    • oxygen administration,
    • intravenous fluid administration for dehydration,
    • medications to increase blood pressure in cases of circulatory collapse,
    • transfusion of blood products in cases of severe bleeding,
    • antibiotics for secondary bacterial infections,
    • dialysis for kidney failure, and
    • endotracheal intubation (placement of a breathing tube) and mechanical ventilation in cases of respiratory failure.

    Avoid acetylsalicylic acid (Aspirin) and nonsteroidal anti-inflammatory drugs (NSAIDs) because of the increased risk of bleeding.

    For the first few days of illness, infected individuals should also be isolated indoors and/or under mosquito netting in order to prevent further mosquito exposure, thus eliminating the potential for further transmission of the disease.


    How long does yellow fever last?

    For individuals with yellow fever who develop the acute mild course of the illness, the symptoms will generally last about three to four days, and most patients will recover fully. For those individuals who develop the more serious toxic phase of the disease and survive, the course of the illness may last for several weeks depending on the severity of illness and any associated complications.

    What is the prognosis for people with yellow fever?

    The prognosis for individuals who develop uncomplicated yellow fever is generally excellent. However, for those patients who go on to develop the toxic phase of yellow fever, case-fatality rates range from 20%-50% depending on the underlying condition of the patient and the availability of supportive resources. If death occurs, it is typically within 10-14 days after the onset of the toxic phase. Infants and those older than 50 years of age tend to have more severe disease and higher mortality rates. Furthermore, host susceptibility and the virulence of the particular infecting strain can also influence mortality rates. In those individuals who survive yellow fever, generally there is no residual permanent organ damage.

    Is it possible to prevent yellow fever?

    Vaccination remains the most effective way of preventing yellow fever. The yellow fever vaccine is a safe vaccine with only rare serious adverse events reported. Since the undertaking of the Yellow Fever Initiative in 2006, health care professionals have made visible progress in combating the disease in West Africa with more than 105 million people receiving the vaccine in mass campaigns.

    The yellow fever vaccine is a live virus vaccine that provides long-lasting immunity after a single dose. It provides immunity (boosts the immune system) against yellow fever in 95% of individuals within one week of its administration. In select cases, certain individuals should get a booster dose. The vaccine is available for adults and children older than 9 months of age. Health care providers recommended vaccination for travelers going to areas where yellow fever is endemic (at least 10 days before going to the area) and to vaccinate local populations who are at risk. Several countries require travelers to demonstrate proof of yellow fever vaccination status for entry in order to prevent the importation and transmission of yellow fever. Check with a local health department for information regarding designated yellow fever vaccination centers.

    Effective mosquito-control measures are also an important component for preventing or minimizing the risk of yellow fever. Avoid mosquito bites by wearing protective clothing (long sleeves and long pants) and remaining in properly screened or air-conditioned accommodations. Furthermore, health care providers advise individuals to apply an EPA-registered insect repellant containing DEET or picaridin on exposed skin; IR 3535 repellent may also be used. These precautions may also help to prevent other mosquito-related infections like Zika.

    What are the side effects of the yellow fever vaccine?

    The yellow fever vaccine can have rare but serious adverse side effects. Health care professionals administer the yellow fever vaccine in designated vaccination centers. Health care providers need to consider the individual’s underlying health, their risk of exposure to yellow fever, and the contraindications to vaccine administration before recommending it. To minimize the risk of serious adverse events, the Centers for Disease Control and Prevention (CDC) provides the following vaccination recommendations:

    Contraindications (conditions in which the vaccine should not be given)

    Which Type of Diabetes Is Worse for COVID?

    Types of diabetes

    COVID-19, the disease caused by the SARS-CoV-2 virus, is a mild illness in most people. People with type 1 diabetes have 3.5 times the risk of dying compared to people without diabetes and people with type 2 diabetes have double the mortality risk with this viral infection.

    COVID-19, the disease caused by the SARS-CoV-2 virus, is a mild illness in most people. But certain conditions increase your risk of having severe symptoms. Among these conditions, diabetes, hypertension, and obesity are common and often cause life-threatening disease.

    Diabetes isn’t the same for everyone. There are two main types of diabetes, type 1 and type 2. They differ in their natural history, treatment, and risk for dangerous COVID-19 disease. You may be concerned about which is worse — type 1 or type 2 diabetes.

    Diabetes is a disorder of glucose management. Glucose is a type of sugar that your body’s cells need to create energy. Insulin, a hormone produced by the pancreas, allows glucose to enter your cells. This hormone is crucial to glucose utilization and control of blood glucose levels. Your glucose levels need tight control. Both too much and too little are harmful.

    There are two types of diabetes:

    In type 1 diabetes, the body’s own immune system destroys the insulin-producing cells in the pancreas. The pancreas can’t produce insulin, and blood glucose levels are uncontrolled. About 5% to 10% of people with diabetes have this type. If you have type 1 diabetes, you need insulin injections every day.

    In type 2 diabetes, the body is unable to produce enough insulin, or the cells don’t respond to it. About 90% or more of people with diabetes have this type. You can control type 2 diabetes with a planned diet, regular exercise, weight loss, and anti-diabetic medications taken by mouth.

    Gestational diabetes is a temporary disorder that happens during pregnancy. 

    Dangers of diabetes in COVID 

    Having diabetes does not increase your risk of getting a COVID infection. But if you do get the disease, it increases your risk of respiratory failure, heart failure, and intensive care unit admission. Severe COVID with diabetes is also associated with high mortality.

    In the U.K., about 5% of the population has diabetes — but almost 30% of COVID deaths are among people with diabetes.

    Severe COVID with diabetes is related to blood glucose control. Among people with diabetes hospitalized with COVID, those with well-controlled blood sugar have better outcomes. People who have high blood sugar levels when admitted to the hospital with COVID have a higher risk of complications and death. 

    People with diabetes have a higher risk of kidney failure during hospitalization with COVID. They are also more likely to need intensive care and ventilator support. That means they have respiratory failure more often than people without diabetes.

    Which is worse — type 1 or type 2 diabetes?

    Both types of diabetes put you at high risk for severe COVID-19 illness. People with type 1 diabetes have 3.5 times the risk of dying compared to people without diabetes. People with type 2 diabetes have double the mortality risk with this viral infection. 

    Scientists have found that people who use insulin have 3.58 times the risk of a bad outcome when they have COVID-19. All people with type 1 diabetes use insulin, but very few with type 2 need it. 

    What increases your risk of severe COVID with diabetes?

    Apart from the type of diabetes you have, a few factors increase your risk for dangerous disease with COVID-19.

    • Male sex
    • Older age
    • Kidney disease
    • Socioeconomic deprivation
    • Previous stroke 
    • Previous heart failure

    You’ll notice that most of these are unchangeable. You can’t do much to reduce your risk if you get COVID. If you have diabetes with one or more of these factors, you should take additional precautions to keep yourself safe from COVID infection.

    Safety from severe COVID

    If your diabetes puts you at risk of severe COVID, you need to safeguard yourself.

    • Keep your diabetes under control. See your doctor regularly, and follow testing and treatment diligently. 
    • Avoid contact with people, especially crowds. Meet people outdoors if possible. 
    • Get vaccinated. You’ll have protection 14 days after the second dose. 
    • Consider using telehealth services for your medical consultations. 
    • Wear a mask in stores, on public transport, and in other enclosed places where you come in contact with people.
    • Wash or sanitize your hands frequently.

    Type 1 diabetes appears to be more dangerous than type 2 during COVID infection — but diabetes of either type increases your risk of a bad outcome. If you have diabetes, you should take all the recommended precautions to avoid the infection.

    Other conditions, like obesity and high blood pressure (hypertension), also increase the risk of severe COVID disease. If you have diabetes with hypertension, make sure to get effective treatments for both. Reducing obesity will also benefit your diabetes control and reduce your risk of severe COVID. 

    Regardless of the type of diabetes you have, high blood sugar levels increase your risk. If your blood sugar is high when you get COVID, you’re at a higher risk of getting severe symptoms. Regular diabetes treatment and monitoring will keep your glucose at the recommended levels. That will help keep you safe from severe COVID.


    Diabetes: What Raises and Lowers Your Blood Sugar Level?
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    Medically Reviewed on 1/24/2022



    Centers for Disease Control and Prevention: “Underlying Medical Conditions Associated with Higher Risk for Severe COVID-19: Information for Healthcare Providers,” “What is Diabetes?”

    Diabetes Care: “Clinical Characteristics and Outcomes of Patients With Diabetes and COVID-19 in Association With Glucose-Lowering Medication.”

    Journal of the American Medical Association: “Presenting Characteristics, Comorbidities, and Outcomes Among 5700 Patients Hospitalized With COVID-19 in the New York City Area.”

    Journal of Clinical Medicine: “COVID-19 and Diabetes.”

    The Lancet Diabetes & Endocrinology: “Associations of type 1 and type 2 diabetes with COVID-19-related mortality in England: a whole-population study,” “Risk factors for COVID-19-related mortality in people with type 1 and type 2 diabetes in England: a population-based cohort study.”

    National Health Service: “Advice for people at high risk from coronavirus (COVID-19),” “Diabetes.”

    Which Types of Implants Are the Best?

    Breast implantations are performed for breast reconstructive or augmentation purposes

    Breast implantations are performed for breast reconstructive or augmentation purposes because of certain reasons such as:

    • Post mastectomy as a treatment for breast cancer or preventive treatment against breast cancer
    • For cosmetic purposes to make the breasts look bigger and fuller

    Two basic types of breast implants that are considered safe and best for breast augmentation and breast construction:

  • Saline-filled implants: In this, silicone shells are filled with sterile saline (saltwater). Some are pre-filled, and others are filled during the implant operation.
  • Silicone gel-filled implants: In this, silicone shells are filled with silicone (a plastic gel). Although many women say that silicone gel implants feel more like real breasts than saline implants, they possess more risk of leakage and subsequent complications.
  • Both types have their advantages and disadvantages. You must talk to your surgeon and make an informed choice.

    • Risk and complications: There is a possibility of rupture and leakage from breast implants. If the saline implant ruptures, saline water gets safely absorbed by the body and the implant deflates. However, silicone may leak outside the shell and cause painful complications. The important thing is when silicone breast implants rupture, they may not show any immediate symptoms, and this is known as silent rupture.
    • Age limit: Because the breasts continue to develop until women reach their late teens or early 20s, the U.S. Food and Drug Administration (FDA) requires women to be at least 18 years old to get breast augmentation with saline-filled implants and at least 22 years old to receive silicone implants.

    How much does it cost?

    The cost of breast implants depends on the location and type of implants used. It may also be varied based on surgeons’ skills and procedure techniques used. Generally, these types of surgeries range from $5,000 to $10,000. The health insurance does not cover surgeries because these surgeries are performed for cosmetic purposes.

    What happens during breast implantation surgery?

    Before breast implantation, your surgeon will perform medical evaluation and ask you about your preferences. They will request you to stop using certain medications such as anti-blood-clotting medications a few days or weeks before surgery.

    There are certain surgical techniques in which you can perform your breast augmentation on an outpatient basis. The procedure time is just 2-2.5 hours.

    • The surgeon will perform the surgery under general anesthesia, during which you will fall asleep and will not feel any pain.
    • The surgeon will make a cut under your breast, under your arms, or around your nipples depending on your preferences, implant type, your body type, and requirements.
    • Then, the surgeon will place the breast implants inside the pockets made above or below your chest muscles.
    • The surgeon will close the cuts with sutures or surgical tape after the procedure is completed.


    Plastic Surgery: Before and After Photos of Cosmetic Surgeries
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    What to expect after breast implantation surgery?

    After breast implantation, you can expect the following things:

    • Hospital stay: You will require a short hospital stay, depending on the procedure type and your condition.
    • Dressing and draining of the wound: The surgeon will cover your breasts with a gauze and drainage tube. They will remove this in a few days, and you may need to wear a surgical bra until full recovery.
    • Swelling and scars: You will probably have some swelling in the area where the surgery was performed. The swelling will improve, and the scar will fade overtime.
    • Pain-relievers: Your doctor may prescribe some pain relievers such as acetaminophen to relieve discomfort.
    • Precautions: Avoid any heavy lifting for up to 6 weeks after getting breast implantation surgery.

    How to take care of breast implants after the surgery?

    Aftercare includes:

    • Implant replacement: These breast implants are not designed to last a lifetime. Therefore, you may require to replace them whenever there are any complications such as asymmetrical or abnormal shapes and sizes of your breasts over the time.
    • Safety reassurance: If you have silicone gel-filled implants, you will need a magnetic resonance imaging (MRI) scan 3 years after the implant surgery and then after every 2 years to receive reassurance of implant safety and check for any ruptures. If any rupture is suspected in the implants, you will need to remove or replace them.
    • Difficult to locate the breast cancer tissue: Breast implants can make any breast cancer tissue difficult to locate on a mammogram (testing of your breasts for any tumors/cancerous growth). Therefore, the risk of breast cancer increases after these breast implants.
    • Breastfeeding issues: Some nursing mothers who underwent breast implantation may face difficulty in breastfeeding.

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    Medically Reviewed on 4/3/2021


    Which Way Should You Face Your Bed? Rules for a Better Sleep

    Ayurveda and vastu shastra

    There is no convincing evidence that your bed should face a certain way. However, feng shui recommends that you should point your headboard toward the south.

    There is a lack of convincing scientific evidence to say that you should face your bed in a “particular” way or direction. However, as per the ancient Chinese practice, feng shui, you should face your headboard toward the south. The practice also recommends keeping your bed away from doors and windows.

    Ayurveda suggests sleeping on your left side so that you breathe properly and the body functions well.

    Vastu shastra is the traditional Indian system of architecture. Sleeping with your head pointing north draws energy out of the body, disturbing body-mind-spirit integration. Sleeping with the head facing north and feet toward the south is the worst sleeping position. It is based on the belief that our body is polar, and it needs to face toward the south to attract opposite poles during sleep.

    While many of the beliefs in both feng shui and vastu shastra are anecdotal, clinical research on the same is lacking. However, it would not harm you to sleep in the way the practices recommend. Ultimately, it is your personal choice to face your bed the way you prefer. More than the direction of the bed, it is important to have good sleep hygiene for a good night’s sleep.

    Which sleeping position is the healthiest?

    Most doctors recommend fetal and log positions to be the healthiest positions to sleep in. When your back is straight, it is generally a good sleeping position. The two positions allow you to sleep with a straight spine

  • Fetal position: Fetal position is the most popular sleeping position. Sleeping in the fetal position allows your spine to rest in its natural alignment. Per research, this position might also help prevent neurological conditions such as Alzheimer’s disease or Parkinson’s disease.
  • Log position: Log position is when you sleep on your side but with both arms down, close to your body. Nearly 15 percent of people sleep like this. To make it better, try placing a soft pillow or folded blanket between your knees. This will ease the pressure on your hips. 
  • We usually prefer to sleep in the most comfortable position. However, not all things that are comforting turn out to be healthy. Some sleeping positions that may not be healthy include the following

    • Freefall position: The freefall position is lying on your stomach, that is, in the direction of gravity. Your arms are tucked under your pillow or on either side of your head. Sleeping in the freefall position can lead to low back, neck pain and sleep apnea attacks. If you find difficulty sleeping in positions other than freefall, at least use a soft pillow under your forehead and sleep facing the mattress. This can prevent neck pain and keep your airway open.
    • Soldier position: Soldier position is when you sleep on your back, that is, facing the ceiling. This position is known for causing snoring and can give rise to back pain. For people with sleep apnea, this is the worst position. Try sleeping in the fetal or the log position. If you find difficulty leaving the soldier position, try placing a pillow or folded blanket under the knees.
    • Starfish position: Starfish is the soldier position with the legs spread out sideways. Like the soldier position, the starfish position is also not a suitable sleeping position for people with sleep apnea. To make it better, place a pillow under your knees before you doze off.

    Medically Reviewed on 1/27/2021


    Medscape Medical Reference

    International Journal of Scientific & Technology Research

    The Better Sleep Council