What is Yellow Fever?
Yellow fever is a serious viral disease transmitted by infected mosquitoes, primarily Aedes and Haemagogus species. It occurs in parts of sub-Saharan Africa and tropical South America. The virus causes a wide range of illness, from mild flu-like symptoms to severe liver disease with bleeding and jaundice (yellowing of the skin and eyes). In severe cases, yellow fever can be fatal.

Why Vaccinate?
Yellow fever vaccination is:

• Highly effective — A single dose provides lifelong protection in most individuals

• Required for entry into certain countries (International Health Regulation requirement)

• Crucial for personal protection, especially when traveling to endemic or outbreak-prone areas

Who Should Get the Yellow Fever Vaccine?

• Travelers aged 9 months and older going to or through areas where yellow fever is endemic or where vaccination is a visa requirement

• People working in or traveling to rural or forested regions with high mosquito exposure

• Laboratory workers handling the yellow fever virus

Vaccine Details

• Name: YF-VAX® (U.S.) or Stamaril® (available globally)

• Type: Live, attenuated virus vaccine

• Dose: Single subcutaneous or intramuscular injection

• Protection begins: ~10 days after vaccination

• Duration: Usually provides lifelong immunity, though some countries may still require proof of recent vaccination

International Certificate of Vaccination (Yellow Card)

• Issued at the time of vaccination by an authorized yellow fever vaccination center

• Becomes valid 10 days after vaccination

• May be required for entry into certain countries — failure to provide proof can result in denied entry or quarantine

Who Should NOT Get the Vaccine?

Yellow fever vaccine is generally not recommended for:

• Infants under 6 months

• People with severe allergies to eggs or gelatin

• Individuals with weakened immune systems (e.g., HIV/AIDS, cancer, immunosuppressive therapy)

• Those with a history of severe allergic reaction to a previous yellow fever vaccine dose

• Pregnant or breastfeeding women (unless travel is unavoidable and benefits outweigh risks)

In such cases, a medical waiver may be issued for travel, though this may not be accepted by all countries.

Side Effects and Risks

Most people experience only mild side effects:

• Headache

• Low-grade fever

• Muscle aches

• Soreness at the injection site

Rare but serious risks include:

• Allergic reaction

• Yellow fever vaccine-associated neurotropic disease (YEL-AND)

• Yellow fever vaccine-associated viscerotropic disease (YEL-AVD)

These risks are rare, particularly in healthy individuals under 60.