Yellow Fever Vaccine

The yellow fever vaccine is administered subcutaneously to individuals above 9 months old who reside in or travel to yellow fever endemic regions, including tropical areas of Africa and Central and South America. Along with vaccination, it is necessary to take precautions against mosquito bites in these regions.

Yellow fever infections are typically asymptomatic, but in some cases, they can cause fever, headache, body pain, nausea, and vomiting. In severe cases, yellow fever can be life-threatening, affecting multiple organs such as the liver, kidneys, brain, and gastrointestinal tract, leading to jaundice, renal failure, hemorrhage, and shock. Serious yellow fever disease has a mortality rate of 20% or higher, according to studies.

The yellow fever vaccine is prepared using the 17D-204 strain of yellow fever virus, cultured in living avian leukosis virus-free (ALV-free) chicken embryos. The vaccine triggers a mild infection at the injection site, stimulating an immune response and production of antibodies that prevent disease when exposed to the wild-type yellow fever virus. It also contains substances that preserve, stabilize, and enhance immune response.

Yellow fever vaccine is used to prevent yellow fever in:

• People residing in or traveling to endemic areas
• Individuals traveling internationally through yellow fever countries
• Laboratory personnel handling virulent yellow fever virus or concentrated vaccine preparations

Warnings

• Do not administer yellow fever vaccine to individuals with a history of hypersensitivity to chicken eggs or any vaccine component
• Infants under 6 months should not receive the vaccine unless exposure to the virus is unavoidable
• Infants under 9 months should not receive the vaccine due to the risk of encephalitis
• Avoid vaccination in individuals with acute or febrile disease
• Avoid vaccination in individuals with compromised immunity
• Avoid vaccination in breastfeeding women
• Yellow fever vaccine can cause multi-organ failure or symptoms similar to wild-type yellow fever virus infection
• Individuals over 60 years are at higher risk and should assess the risks and benefits of vaccination based on exposure risk

Side Effects of Yellow Fever Vaccine

Common side effects of yellow fever vaccine include:

• Headache
• Malaise
• Chills
• Fever
• Asthenia (weakness)
• Myalgia (muscle pain)
• Injection site reactions such as pain, redness, swelling, blister, residual mass, and hypersensitivity
• Rash
• Urticaria (hives)
• Asthma
• Anaphylaxis (severe allergic reaction)

Rare side effects of yellow fever vaccine include vaccine-associated neurotropic disease and vaccine-associated viscerotropic disease, including multi-organ failure.

Seek immediate medical attention if you experience the following symptoms or serious side effects:

• Severe heart symptoms like fast or pounding heartbeats, fluttering in the chest, shortness of breath, and sudden dizziness
• Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, unsteadiness
• Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out
• Serious eye symptoms like blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights

This is not an exhaustive list of side effects or adverse reactions. Consult your doctor for medical advice about serious side effects or adverse reactions. Report side effects or health problems to the FDA at 1-800-FDA-1088.

Yellow Fever Vaccine Dosages

Injection (17D-204 strain)

• Minimum of 4.74 log 10 plaque-forming units/0.5ml

Yellow Fever

Adult:

• Prophylaxis: 0.5ml subcutaneously at least 10 days before travel
• A single, lifetime dose of yellow fever vaccine is generally sufficient, but some high-risk groups may require a booster dose as recommended by the CDC’s Advisory Committee on Immunization Practices

Pediatric:

• Infants over 6 months (off-label): 0.5ml subcutaneously for 1 dose at least 10 days before travel
• Infants over 9 months: 0.5ml subcutaneously for 1 dose at least 10 days before travel
• A single, lifetime dose of yellow fever vaccine is generally sufficient, but some high-risk groups may require a booster dose as recommended by the CDC’s Advisory Committee on Immunization Practices

Booster/additional doses for high-risk groups:

• A primary dose of yellow fever vaccine provides long-lasting protection for most travelers
• Additional doses may be necessary for specific groups, such as pregnant women, hematopoietic stem cell transplant recipients, individuals infected with HIV, and certain laboratory workers

Drug Interactions with Yellow Fever Vaccine

Inform your doctor about all medications you are taking to check for possible drug interactions. Do not start, stop, or change the dosage of any medication without your doctor’s recommendation.

• Severe interactions with yellow fever vaccine include: belimumab, certolizumab pegol, ibrutinib, ifosfamide, ixekizumab, lomustine, mechlorethamine, melphalan, methotrexate, onasemnogene abeparvovec, oxaliplatin, procarbazine, secukinumab, and ustekinumab
• Other interactions include: anthrax immune globulin, belatacept, betibeglogene autotemcel, and obinutuzumab
• Chloroquine may interact with yellow fever vaccine

The above list does not cover all possible interactions or adverse effects. For more information on drug interactions, use the RxList Drug Interaction Checker.

Always inform your doctor or healthcare provider about all medications you use, including prescription and over-the-counter drugs, along with their dosages. Keep a list of this information. If you have any questions regarding the medication, consult your doctor or healthcare provider.

Pregnancy and Breastfeeding

• There is limited information available on the use of yellow fever vaccine during pregnancy. It should be administered only if travel to an endemic area is unavoidable, and the infant should be monitored after birth.
• Women of pregnancy potential should avoid becoming pregnant for 4 weeks after receiving the yellow fever vaccine.
• Yellow fever vaccine should not be administered to breastfeeding mothers as it may pose serious risks to the breastfed infant, including encephalitis.

Additional Information about Yellow Fever Vaccine

• Prior to traveling to yellow fever endemic regions, consult your healthcare provider, travel agent, or airlines to acquire vaccination requirements. Some countries strictly enforce these requirements, particularly for travelers from Africa or South America to Asia.
• Local health departments, the CDC, and WHO can provide additional information.
• When in yellow fever endemic regions, take precautions to protect yourself from mosquito bites, such as using insect repellent, wearing protective clothing, and staying in well-screened or air-conditioned areas.

By clicking Submit, you agree to the MedicineNet’s Terms & Conditions & Privacy Policy and understand that you may opt out of MedicineNet’s subscriptions at any time.

Summary

Yellow fever vaccine is a live, attenuated viral vaccine used to prevent yellow fever, a viral infection transmitted by mosquitoes. Common side effects include headache, malaise, chills, fever, weakness, myalgia, injection site reactions, and hypersensitivity reactions. Do not take if trying to become pregnant or breastfeeding.