ACIP updates schedules for vaccines against Japanese encephalitis, anthrax
The CDC’s Advisory Committee on Immunization Practices voted unanimously to recommend changes to booster schedules for vaccines against Japanese encephalitis virus and anthrax.
The ACIP conducted three separate 15-0 votes on recommendations regarding the Japanese encephalitis (JE) virus vaccine.
In information presented before the vote, the CDC noted that for most travelers to Asia, the risk for JE is low, “but varies based on travel destination, duration, season, activities and accommodations.”
The ACIP first voted on updating recommendations for the use of JE vaccine for travelers and those considering moving to JE-endemic areas.
“JE vaccine also should be considered for shorter-term (eg, < 1 month) travelers with an increased risk of JE-based travel duration, season, location, activities and accommodations,” the recommendation read. “Vaccinations also should be considered for travelers to endemic areas who are uncertain of specific duration of travel, destination or activities.”
The ACIP voted not to recommend the JE vaccine for travelers with “very low risk” itineraries, including shorter-term travel to urban areas or travel outside a defined JE virus transmission season.
The second vote regarding the JE vaccine was for a new recommendation that the primary vaccination schedule in adults aged 18 to 65 years should be two doses on days 0 and 7 to 28. The FDA approved an accelerated schedule of 0 and 7 days as an alternative to the standard schedule of 0 to 28 days for Ixiaro (Valneva) in October 2018.
The third vote was a new recommendation that a booster, or third, dose of JE vaccine be given at least 1 year after completing the primary JE vaccine series if ongoing exposure or re-exposure to the virus is expected.
The ACIP also voted 15-0 to recommend that “among persons not currently at high-risk of exposure to [Bacillus anthracis] who have previously primed with [anthrax vaccine absorbed (AVA)] and wish to maintain protection, a booster dose of AVA may be give every 3 years.”
The ACIP work group noted that data showed that a booster interval of up to 3 years provided “a robust amnestic immune response” in such people.
The committee held an initial vote on the wording of the recommendation, changing the word “should” to “may” because committee members thought it more accurately reflected the recommendation.
“The ACIP committee’s approval of the policy changes regarding anthrax vaccine use for pre-exposure prophylaxis will improve our ability to prepare for an anthrax event,” William Bower, MD, epidemiology team lead in the CDC’s Bacterial Special Pathogens Branch, told Infectious Disease News. “These changes give public health officials more tools to use in the face of an anthrax response.” – by Bruce Thiel
Disclosure: Bower works for the CDC.