according to a vote at a meeting of the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices.
Japanese encephalitis (JE) virus is a mosquito-borne flavivirus and those at risk for infection include travelers to countries where JE is endemic, as well as laboratory personnel who work with the virus.
The committee voted unanimously 15-0 in favor of the recommendations, which also advised vaccination for those whose travels in endemic areas are uncertain, but not for travelers with low-risk itineraries “such as shorter term travel limited to urban areas or travel that occurs outside of a well-defined JE virus transmission season.”
Susan Hills, MD, of the of the CDC’s National Center for Emerging and Zoonotic Infectious Diseases, presented data in support of the recommendations.
A second unanimous vote confirmed recommendations for a primary series schedule for JE vaccination for adults aged 18-65 years as “two doses of vaccine administered on days 0 and 7-28.”
The third vote, also a unanimous 15-0, updated recommendations for a JE booster dose. The new recommendation is that adults and children receive a booster dose (a third dose) at least a year after completion of the primary JE vaccine series “if ongoing exposure or re-exposure to JE virus is expected.”
The currently available Japanese encephalitis vaccine in the United States is an inactivated Vero cell culture-derived vaccine marketed as IXIARO that was approved in March 2009 for individuals aged 17 years and older and approved in May 2013 for children aged 2 months through 16 years.
The ACIP members had no financial conflicts to disclose.