ATLANTA -- The World Health Organization's (WHO) delay in selecting the influenza A (H3N2) strain for the 2019-2020 flu season is expected to affect the FDA, leading to a delay in the agency's own decision on strains for next season's vaccines.
These questions came up during a presentation at the Advisory Committee on Immunization Practices (ACIP) meeting here, where committee members also voted 15-0 on updates to recommendations for both vaccines against Japanese encephalitis for travelers and 15-0 for recommendations for a booster dose of anthrax vaccine for persons not at high risk.
Next week, the FDA's will meet. It was expected to select the influenza strains for the vaccine for the 2019-2020 influenza season, which has always followed the WHO's recommendations from a meeting in February. But at the meeting , the WHO elected to delay their selection on the influenza A (H3N2) strain until March 21, citing the need for more time to review data.
When asked about the WHO delay, Doran Fink, MD, an ex officio member of ACIP representing the FDA, said the agency would "likely delay" their decision on the influenza A (H3N2) strain until the WHO makes their decision. One member of the ACIP asked about the "programmatic implications" of this delay, such as not being able to produce enough vaccine in time for the next flu season; Fink replied that he could not comment on "downstream effects" of the potential decision at this time.
This meeting was also the first unveiling of the new procedure the ACIP has for public comment, which was 75 minutes long and prior to the votes. However, hardly any of the comments were actually about Japanese encephalitis or anthrax vaccines, but instead, lectured the ACIP about vaccine science and shared personal anecdotes. One commenter stated that recent approval of a hepatitis B vaccine was akin to "a violation of the Nuremberg codes."
Updated Recommendations
A vote was taken on the timing of the booster dose for the anthrax vaccine in persons not at current high risk of exposure, such as potential first responders in a mass event and veterinarians who deal with infected animals. After the committee engaged in some wordsmithery, the ACIP members voted that a booster dose of anthrax vaccine (AVA) may be given every 3 years to persons not currently at high risk who had been previously primed with AVA and wish to maintain protection.
William Bower, MD, of the CDC, told the committee this was for emergency responders in "high-target areas," and that spreading out the booster dose interval would potentially make getting the booster dose "more appealing" for this population.
The ACIP also voted on several updates to language regarding Japanese encephalitis vaccine (JE-VC) for travelers. The CDC clarified that these votes were to "simplify previous language, and include explanations to help clinicians in their decision making."
The first vote clarified recommendations for providers about which patients should receive the vaccine, such as persons moving to an endemic country, longer-term travelers, as well as people going where it was not recommended, such as shorter term travelers in urban areas or travelers outside of a "well-defined Japanese encephalitis season."
Votes were also taken for a new recommendation on Japanese encephalitis primary series schedule in adults (ages 18-65) with two doses administered on day 0 and days 7-28, and a booster dose of JE-VC for adult and child travelers. The third vote recommended a booster dose given at ≥1 year after completion of the primary JE-VC series if "ongoing exposure to JE virus is expected."
As always, recommendations of the ACIP are not final until they are published in the Morbidity and Mortality Weekly Report.