Vaccine Info

YF-VAX Yellow Fever Vaccine

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Last reviewed
November 6, 2023

YF-VAX® Yellow Fever Vaccine 2023

Sanofi Pasteur YF-VAX® vaccine is prepared by culturing the 17D-204 strain of yellow fever virus in living avian leukosis-free chicken embryos. The U.S. Food and Drug Administration (FDA) Approved the YF-Vax vaccine (BL 103915), which contains sorbitol and gelatin as a stabilizer, is lyophilized, and is hermetically sealed under nitrogen, and no preservative is added. The YF-VAX vaccine must be reconstituted immediately before using the sterile diluent provided (Sodium Chloride Injection USP). After reconstitution, YF-VAX is a slight pink-brown suspension and complies with the yellow fever vaccine standards of the World Health Organization (WHO).

The FDA reported that 'two live, attenuated yellow fever vaccines, strains 17D-204 and 17DD, were derived in parallel in the 1930s. Historical data suggest that these "17D vaccines" have identical safety and immunogenicity profiles. Therefore, vaccination with 17D strain vaccines is predicted to elicit an immune response similar to wild-type infection. This response is presumed to result from the initial infection of cells in the dermis or other subcutaneous tissues near the injection site, with subsequent replication and limited spread of the virus leading to the processing and presentation of viral antigens to the immune system, as would occur during infection with wild-type yellow fever virus. Therefore, the humoral immune response to the viral structural proteins, as opposed to a cell-mediated response, is most important in the protective effect of 17D vaccines.

Yellow fever is an epidemic-prone, vaccine-preventable disease caused by an arbovirus transmitted to humans by the bites of infected  Aedes and  Haemagogus mosquitoes. The WHO publishes the Eliminate YelFeverever Epidemics global strategy. In accordance with the IHR (2005) third edition, the international certificate of vaccination against yellow fever becomes valid ten days after vaccination, and the validity extends throughout the life of the person vaccinated. A single dose of a WHO-approved yellow fever vaccine can confer sustained immunity and life-long protection against yellow fever disease. 

Sanofi Pasteur has worked with the U.S. FDA, Centers for Disease Control and Prevention (CDC), the U.S. Dept of Defense (DoD), and other stakeholders since 2016. As a result, vaccination against yellow fever remains available for travelers, U.S. government employees, the military, and other response groups. On December 26, 2020, the FDA licensed the new Sanofi Pasteur YF-VAX production facility, and doses continue progressing through manufacturing. Efforts are underway to build inventory and supply of YF-VAX, which will continue to be prioritized for the U.S. military.

Additionally, Sanofi Pasteur announced that effective April 5, 2021, YF-VAX® is available in the U.S. by authorized YF-VAX providers. NDC Code: 49281-915-01, STN: 103915/5220, issued on August 6, 2019.

Sanofi Pasteur, a Sanofi company, aims to support continued access to yellow fever vaccination for travelers to international destinations where the yellow fever vaccine is required or recommended. Sanofi is dedicated to supporting people through their health challenges.

YF-Vax Price

Sanofi Pasteur and the U.S. CDC confirmed the YF-VAX® vaccine is available in the U.S. Various pharmacies and services indicate the YF-Vax vaccine list price is over $150. Sanofi reported that third-quarter 2022 Travel Vaccine revenues increased 64.6% to €146 million. And Sanofi's Patient Connection® offers various vaccine price savings. Sanofi has live support specialists at (800) 633-1610 to answer patients' questions. The CDC's Vaccines For Children program provides vaccines at no cost to qualifying children. And InstantRx™ is a digital gateway empowering people to find lower-priced medicines and vaccines easily.

YF-VAX Availability 2023

As of 2023, YF-VAX was available at Yellow Fever Vaccination Clinics in the U.S. Additional yellow fever-certified pharmacies.

YF-VAX Indication

Yellow fever is an acute viral hemorrhagic disease transmitted by infected mosquitoes. The "yellow" in the name refers to jaundice that affects some patients. The YF-VAX vaccine is indicated for active immunization to prevent yellow fever in persons nine months of age and older at increased risk for yellow fever to help prevent them from getting it. However, vaccination with YF-VAX may not protect all individuals. 

YF-VAX should not be given to individuals who have experienced a severe allergic reaction to eggs, egg products, or any vaccine component (gelatin). In addition, the following persons should not receive YF-VAX: infants younger than nine months of age due to an increased risk of brain inflammation, women breastfeeding infants younger than nine months, and individuals with a severely suppressed or compromised immune system. Therefore, the disease risk versus a severe adverse event should be assessed before vaccine administration. 

Geriatrics: YF-VAX® is indicated in persons 60 years of age and above. Pediatrics: YF-VAX® is indicated in persons nine months of age or older. Vaccination of infants under nine months of age IS CONTRAINDICATED because of the risk of encephalitis, and travel of such persons to rural areas in yellow fever endemic zones or countries experiencing an epidemic should be postponed or avoided whenever possible. Pregnant Women: Pregnant women should be considered for immunization only if travel to an area with a risk of yellow fever is unavoidable. It is also unknown whether the YF-VAX vaccine can cause fetal harm when administered to a pregnant woman or affect reproductive capacity. Therefore, the YF-VAX vaccine should only be given to a pregnant woman if needed. In addition, the seroconversion rate to 17D vaccines is markedly reduced in pregnant women. 

YF-VAX Side Effects

The most common side effects of YF-VAX include swelling and pain at the injection site, headache, generalized muscle aches or discomfort, and fever. Other side effects may occur. YF-VAX vaccine should not be given to an individual who has experienced a severe allergic reaction to eggs, egg products, or a vaccine component using gelatin. A severe allergic reaction (e.g., anaphylaxis) may occur following the use of the YF-VAX vaccine, even in individuals with no prior history of hypersensitivity to the vaccine components. Rarely the yellow fever vaccine has been associated with disease affecting multiple organs, including brain inflammation.

YF-VAX Breast Milk

Since 2010, there have been health concerns about lactating mothers breastfeeding infants following yellow fever vaccinations. As of 2023, two serious adverse events have been reported in breastfed infants whose mothers were vaccinated with the Yellow Fever vaccine. Until more information is available, the Yellow Fever vaccine should be avoided in breastfeeding women, says the U.S. CDC.

YF-VAX Drug Interactions

Data are limited regarding the drug interaction of the YF-VAX vaccine with other vaccines, such as the Measles (Schwartz strain) vaccine, diphtheria, tetanus toxoid, and pertussis vaccine adsorbed. Hepatitis A and Hepatitis B vaccines, meningococcal vaccine, Menomune® – A/C/Y/W-135, and typhoid vaccine, Typhim Vi®,2,12,34 have been administered with yellow fever vaccine at separate injection sites. No data exist on possible interference between yellow fever and rabies or Japanese encephalitis vaccines.

YF-VAX Dosage

YF-VAX is administered as a single subcutaneous injection of 0.5 mL of reconstituted vaccine. Do not administer YF-VAX by intravascular, intramuscular, or intradermal routes. A single dose protects most for ten years for most people. Sanofi Pasteur's complete YF-VAX Vaccine Prescribing Information is available. The vial stoppers for YF-VAX and diluent are not made with natural rubber latex.

Yellow Fever Endemic Countries

Yellow fever vaccination is required by law upon entry to certain countries irrespective of the traveler's country of origin and in other countries when travelers are coming from endemic areas. The WHO and UNICEF reported that the routine Y.F. vaccination coverage was 48% in the African region in 2021. However, the national coverage in the countries of concern was low except for Ghana (88%): Congo (69%), Cote D'Ivoire (69%), Niger (67%), Cameroon (57%), DRC (56%), Nigeria (54%), CAR (41%), and Chad (35%).

Yellow Fever International Certificate of Vaccination or Prophylaxis (ICVP)

Certain countries may have requirements to protect individual travelers and countries from the risk of importing or spreading the yellow fever virus. These requirements apply to the country you will be visiting; in that case, you may need the 'yellow fever card,' the International Certificate of Vaccination (ICVP), or Prophylaxis as proof of vaccination. The ICVP becomes effective ten days after vaccination.

YF-VAX Vaccine News

October 28, 2023 - The Africa CDC confirmed active yellow fever outbreaks in seven countries.

April 25, 2023 - The PAHO confirmed additional yellow fever cases and related fatalities.

January 15, 2023 - The WHO Africa reported one yellow fever-related fatality in unvaccinated young women in Guinea.

January 3, 2023 - The WHO African Region reported the risk at the regional level was re-assessed as moderate in December 2022 (high in November 2021 and June 2022). The global risk remains low, as no cases related to this current African outbreak have been reported outside the African region. 

September 2, 2022 - According to the WHO EYE strategy, twenty-seven African countries are at high risk for yellow fever based on the timing and intensity of yellow fever virus transmission, transmission potential, and urban risk assessment. The chance at the global level is assessed to be low as no exported cases of yellow fever linked to these 12 countries with probable or confirmed cases since January 2021 have been reported.

July 31, 2022 - According to the U.S. CDC, about thirty countries are 'endemic' for the mosquito-carrying yellow fever virus. 

March 8, 2022 - BMC reported, 'Changing epidemiology of yellow fever virus in Oyo State, Nigeria.'

April 5, 2021 - The U.S. CDC confirmed Sanofi Pasteur announced that YF-VAX is once again available for purchase in the USA. Providers with a current Yellow Fever Vaccination Stamp issued by their state or territorial health department may order YF-VAX from the manufacturer.

December 23, 2020 - Sanofi Pasteur confirmed the U.S. Expanded Access Investigational Drug Application Program (EAP) for STAMARIL® would continue into 2021. Therefore, when YF-VAX returns, there will be a brief period of transition to discontinue the STAMARIL EAP.

June 25, 2020 - The U.S. FDA has licensed Sanofi Pasteur's new U.S. YF-VAX® vaccine production facility, and doses continue progressing through manufacturing. 

December 23, 2019 - Sanofi has worked with the U.S. FDA to provide the STAMARIL vaccine through an Expanded Access Program (EAP) during the YF-VAX vaccine shortage.

August 6, 2019 - The U.S. FDA approved an Expanded Approval Letter for the YF-VAX yellow fever vaccine.

May 2, 2019 – A new state-of-the-art Yellow Fever Vaccine production facility in the USA has been licensed by the Food & Drug Administration (FDA). The production transition of YF-VAX continues, said Sanofi Pasteur in a statement.

January 25, 2018 - Brazil launched a mass immunization campaign to deliver fractional doses of yellow fever vaccine to residents of 69 municipalities in Rio de Janeiro and São Paulo. 

June 15, 2016 - FDA Approval Letter - To revise the YF-VAX  package insert to align Booster Dosing language with recent changes to International Health Regulations and WHO/ACIP recommendations and modify the text throughout the document to clarify and update the presented information.

YF-VAX Yellow Fever Vaccine Clinical Trials

YF-VAX continues to be studied in various clinical trials.