Yellow Fever Vaccine Booster Doses: Recommendations of the Advisory Committee on Immunization Practices, 2015

J. Erin Staples, MD; Joseph A. Bocchini Jr., MD; Lorry Rubin, MD; Marc Fischer, MD

Disclosures

Morbidity and Mortality Weekly Report. 2015;64(23):647-650. 

In This Article

Yellow Fever Vaccine Long-term Immunogenicity Data

No data are available on vaccine efficacy or protective antibody titers (i.e., seroprotection) related to long-term immunogenicity after yellow fever vaccination. Benefits considered critical in assessing the need for booster doses of yellow fever vaccine for U.S. travelers or laboratory workers included vaccine effectiveness (i.e., a lack of vaccine failures) and evidence of seropositivity (i.e., yellow fever virus–specific antibodies detected in a blood sample).[3]

Vaccine Effectiveness

A total of 23 vaccine failures were identified after the administration of >540 million doses of yellow fever vaccine.[3] Of the 23 cases, five occurred <10 days after vaccination and were excluded because most persons are not expected to develop protective titers in that timeframe.[5] Of the remaining 18 cases, 16 (89%) occurred in persons who reported receiving a dose of the vaccine within the previous 10 years.[3] One vaccine failure occurred at 20 years and one at 27 years post-vaccination.

Seropositivity

Thirteen observational studies provided immunogenicity data on 1,137 persons vaccinated ≥10 years previously.[3] Using a random effects model, the estimated seropositivity rate for persons vaccinated ≥10 years previously was 92% (95% confidence interval [CI] = 85%–96%). Of the 164 persons vaccinated ≥20 years previously, the estimated seropositivity rate was 80% (CI = 74%–86%).

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