Evolving Epidemiology of Japanese Encephalitis: Implications for Vaccination
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Purpose of Review
We examine the present global burden of Japanese encephalitis (JE) in endemic populations, summarize published cases in travelers since 2009, examine current guidelines for vaccination for international travelers, and consider challenges in prevention of this vector-borne disease.
We identified 11 JE cases in travelers that were published in peer-reviewed literature since 2009. JE incidence in endemic countries appears to be declining but the number of JE cases reported to the World Health Organization (WHO) varied from estimates derived from other published reports based on serosurveys or sentinel surveillance. Current JE vaccines appear to be safe and are not associated with delayed hypersensitivity in contrast to the older mouse brain vaccine.
Given differences between WHO-reported cases and local surveillance data, future research on true incidence is needed. Regular assessment will inform JE risk in travelers. National and international guidelines on JE vaccination varied; we suggest areas for improvement.
KeywordsJapanese encephalitis Epidemiology Risk estimates Travelers Vaccination
The authors thank Dr. Susan Hills for her thoughtful review and suggestions.
Compliance with Ethical Standards
Conflict of Interest
JPC declares that he has no conflict of interest. LHC reports serving as advisor for Shoreland, Inc. and DSMB for Valneva (unrelated vaccine). DHH reports serving on advisory boards for Valneva and iJET.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as • Of importance •• Of major importance
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