Vaccine Info

YF-VAX Yellow Fever Vaccine

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Last reviewed
September 6, 2022

YF-VAX® Yellow Fever Vaccine For 2022

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. FDA-approved YF-Vax vaccine (BL 103915) contains sorbitol and gelatin as a stabilizer, is lyophilized, and is hermetically sealed under nitrogen. 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 U.S. 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 identical to that induced by wild-type infection. This response is presumed to result from initial infection of cells in the dermis or other subcutaneous tissues near the injection site, with subsequent replication and limited spread of 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. 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. Twenty-seven countries in Africa have been classified as high-risk by the WHO Eliminate Yellow fever Epidemics global strategy. From January 2021 to August 26, 2022, a total of 12 countries in the African region reported 184 confirmed cases and 274 probable cases, including 21 deaths, reflecting ongoing complex viral transmission. 

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 is sufficient to confer sustained immunity and life-long protection against yellow fever disease. A booster dose of the vaccine is not needed and is not required of international travelers as a condition of entry. 

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

Additionally, Sanofi Pasteur announced that effective April 5, 2021, YF-VAX® is available for purchase 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 Vaccine Price

Sanofi Pasteur and the U.S. CDC confirmed the YF-VAX® vaccine is available for purchase in the U.S. Various pharmacies and services indicate the YF-Vax vaccine list price is over $150. 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 easily find lower-priced medicines and vaccines.

YF-VAX Availability

As of September 6, 2022, YF-VAX was available at Yellow Fever Vaccination Clinics. Additional yellow fever-certified pharmacies are identified on this Vax-Before-Travel webpage.

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 who are at increased risk for yellow fever to help prevent them from getting the disease. However, vaccination with YF-VAX may not protect all individuals. 

YF-VAX should not be given to an individual who has experienced a serious allergic reaction to eggs, egg products, or any vaccine component (gelatin). A severe allergic reaction (e.g., anaphylaxis) may occur following the use of YF-VAX, even in individuals with no prior history of hypersensitivity to the vaccine components. In addition, the following persons should not receive YF-VAX: infants younger than nine months of age due to an increased risk of inflammation of the brain, women who are breastfeeding infants younger than nine months of age, and individuals with a severely suppressed or compromised immune system. Rarely the yellow fever vaccine has been associated with disease affecting multiple organs, including brain inflammation. These serious adverse events occur more often in individuals 60 years of age and over. Therefore, the risk of disease versus a serious 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 less than 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 be given to a pregnant woman only if needed. 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 serious 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. In addition, the following persons should not receive the YF-VAX vaccine: infants younger than nine months of age, women who are breastfeeding infants younger than nine months of age, and individuals with a severely suppressed or compromised immune system. Rarely the yellow fever vaccine has been associated with disease affecting multiple organs, including inflammation of the brain.

YF-VAX Drug Interactions

Data are limited regarding 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 Yellow 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 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 YF vaccination coverage was 44% in the African region in 2020. The national coverage in the countries of concern were all under 80% except for Ghana (88%): Congo (69%), Cote D’Ivoire (69%), Niger (67%), Cameroon (57%), DRC (56%), Nigeria (54%), CAR (41%), and Chad (35%). These low YF vaccination coverages indicate the presence of an underlying susceptible population at risk of YF and risk of continued transmission.

And for Brazil, tthe U.S. CDC recommends for all travelers ≥9 months of age going to the following areas: the entire states of Acre, Amapá, Amazonas, Distrito Federal (including the capital city of Brasília), Espirito Santo,* Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraná,* Rio de Janeiro (including the city of Rio de Janeiro and all coastal islands),* Rio Grande do Sul,* Rondônia, Roraima, Santa Catarina,* São Paulo (including the city of São Paulo and all coastal islands),* and Tocantins and designated areas (see map) of the following states: Bahia and Piauí. Vaccination is also recommended for travelers visiting Iguaçu Falls.

Yellow Fever International Certificate of Vaccination or Prophylaxis (ICVP)

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

WHO's Eliminate Yellow Fever Epidemics Strategy

As of 2022, the WHO updated its background on Eliminate Yellow Fever Epidemics (EYE) and its communication rationale.

YF-VAX News For 2016 - 2022

September 2, 2022 - According to the WHO EYE strategy, twenty-seven countries in the African region are high-risk countries for yellow fever based on the timing and intensity of yellow fever virus transmission, transmission potential, and assessment of urban risk. The risk 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. 

April 13, 2022 - The manager of Arboviruses at SES-TO, Cristiane Bueno, stated, 'An unvaccinated tourist in the Tocantins, performing sport fishing, on Lake Peixe/Angical, between the municipalities of Peixe, São Salvador and Paranã, in March 2022, died from yellow fever.'

March 20, 2022 - Nigeria's Under-Vaccinations Empower Yellow Fever Outbreaks.

March 18, 2022 - The Republic of Rwanda's MoH issued a statement saying anyone traveling to yellow fever endemic countries should be vaccinated at least ten days before traveling.

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

December 14, 2021 - The U.S. CDC says since October 2021, there has been a yellow fever outbreak in Ghana with numerous cases, including some deaths, in the following regions: Savannah, Upper West, Bono, and Oti.

December 1, 2021 - The WHO confirmed there is high overall population immunity against YF in Ghana (88% in 2020), pockets of the population, including unvaccinated nomadic people, remain at risk for YF which could result in continued YF transmission. And the International Coordinating Group on Vaccine Provision for Yellow Fever has approved a vaccination campaign targeting over 350 thousand people (9 months - 60 years) in five affected districts. A catch-up vaccination campaign of unvaccinated individuals is also being organized as part of routine immunization strengthening.

November 22, 2021 - MedpageToday wrote: What Caused Brazil's First Urban Yellow Fever Outbreak in 80 Years?

November 18, 2021 - The Municipal Chief Executive for West Gonja Municipal Assembly has urged residents in the Savanna Region to take part in the ongoing mass vaccination exercise for Yellow Fever. Twenty-two people have, so far, been reported to have died from the disease in three districts, including West Gonja Municipal, North Gonja District, and the Bole District.

October 28, 2021 - Sanofi reported its third-quarter 2021 results, revealing travel and other endemic vaccines sales increased 16.9% versus a low 2020 basis.

October 14, 2021 - A team of technical officers in the WHO Africa National Public Health Laboratory have been trained over the last week, aiming at building their capacity to contribute to controlling yellow fever outbreaks.

September 30, 2021 - The U.S. CDC announced an outbreak of yellow fever in Nigeria, first reported in November 2020. Furthermore, 'Travelers to Nigeria should take steps to prevent yellow fever by getting vaccinated at least ten days before travel.'

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 now 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.

October 23, 2020 - The South Sudan Ministry of Health and other partners launched a reactive yellow fever vaccination campaign in Kajo, Keji, Central Equatoria State. The campaign aims to protect over 90,000 individuals aged nine months to 60 years from yellow fever infection.

June 25, 2020 - Sanofi Pasteur's new U.S. YF-VAX® vaccine production facility has been licensed by the U.S. FDA, and doses continue to progress through manufacturing. Efforts are underway to build vaccine supplies, and the U.S. supplies of YF-VAX will continue to be prioritized for the U.S. military. We expect to have more information on the return of YF-VAX in December 2020. The Expanded Access Investigational New Drug Application program for STAMARIL® is expected to continue through 2020. When YF-VAX returns, supplies will be limited, resulting in a gradual transition away from STAMARIL and back to YF-VAX.

December 23, 2019 - Sanofi has worked with the U.S. Food and Drug Administration (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 transition of production of YF-VAX continues, said Sanofi Pasteur in a statement.

March 16, 2018 - Brazil is amidst a yellow fever outbreak, with the mosquito-borne virus reaching popular tourist destinations that do not normally see the disease. Since January 2018, 10 cases of yellow fever have been confirmed in international travelers visiting Brazil, including 4 deaths.

January 25, 2018 - Brazil launched a mass immunization campaign that will deliver fractional doses of yellow fever vaccine to residents of 69 municipalities in the states of 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.