Comparative frequency of specified adverse events following Vero cell culture-derived Japanese encephalitis and Vi capsular polysaccharide typhoid vaccines in U.S. military personnel, July 2011–August 2019. Issue 9 (24th February 2023)

• Record Type: Journal Article
• Authors: Seshadri, Srihari; Martin, Stacey W.; Hills, Susan L.; Collins, Limone C.
• Is Part Of: Vaccine. Volume 41:Issue 9(2023)
• Page Start: 1537
• Page End: 1540
• Publication Date: 2023-02-24
• Subjects: Japanese encephalitis -- Japanese encephalitis vaccine -- Vero cell-derived -- Adverse event -- Retrospective -- Vaccine safety -- Delayed Hypersensitivity -- Convulsions -- Typhoid vaccine; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2023.01.061
• Languages: English
• ISSNs: 0264-410X

Abstract

Highlights: Vero cell culture-derived Japanese encephalitis vaccine (JE-VC; Ixiaro) was approved for adults in 2009. We retrospectively evaluated adverse events of special interest following JE-VC, including hypersensitivity and neurologic events. Data from U.S. military personnel who received JE-VC were compared to data from recipients of Vi capsular polysaccharide typhoid vaccine, a vaccine with a favorable safety profile. The risk of adverse events of special interest was similar between groups, supporting the safety of JE-VC. Abstract: Vero cell culture-derived Japanese encephalitis (JE) vaccine (JE-VC; Ixiaro) was approved in the United States in 2009. The previous JE vaccine, an inactivated mouse brain-derived vaccine, had been associated with rare, but serious, allergic and neurologic adverse events (AE). Studies and AE surveillance have supported JE-VC's safety, but one evaluation among military personnel found elevated hypersensitivity and neurologic AE rates. However, co-administration of multiple vaccines to some personnel might have affected results. We retrospectively compared rates of hypersensitivity and neurologic AEs within 28 days following vaccination of military personnel with JE-VC or parenteral Vi capsular polysaccharide typhoid vaccine administered without other vaccines from July 1, 2011, through August 31, 2019. Rates of most events were similar between the vaccines. Only delayed hypersensitivity reactions occurred more frequently following JE-VC (rate ratio: 4.2, 95 % CI 1.2–15.3; p = 0.03), but rates were low for both vaccines. These results support JE-VC's safety.