As temperatures drop and the days grow shorter, it's time to start thinking about the coming fall and winter and all that those seasons bring. And that, of course, means gearing up for the annual influenza season.
The CDC has done just that -- releasing its yearly flu vaccination recommendations(www.cdc.gov) in Morbidity and Mortality Weekly Report (MMWR) on Aug. 25. The AAFP has adopted those recommendations.
The updated recommendations were discussed and voted on during meetings of the agency's Advisory Committee on Immunization Practices (ACIP) held in October 2016, as well as those in February and June 2017. Here's a rundown of what's new for the coming flu season.
Trivalent influenza vaccines for the 2017-2018 U.S. flu season will contain the following virus strains:
- an A/Michigan/45/2015 (H1N1)pdm09-like virus,
- an A/Hong Kong/4801/2014 (H3N2)-like virus, and
- a B/Brisbane/60/2008-like virus (Victoria lineage).
Quadrivalent vaccines will contain these three viruses plus a B/Phuket/3073/2013-like virus (Yamagata lineage).
As in previous years, multiple vaccine options will be available, although the ACIP continues to recommend that quadrivalent live attenuated influenza vaccine (LAIV4; FluMist) not be used because of concerns about its lack of effectiveness against (H1N1)pdm09 viruses during the 2013-2014 and 2015-2016 seasons.
Two vaccines are newly licensed for use during the 2017-2018 season. They are Seqirus' quadrivalent inactivated influenza vaccine (IIV4) Afluria Quadrivalent(www.fda.gov) -- licensed for use in patients ages 5 years and older -- and Protein Sciences' new IIV4 formulation Flublok Quadrivalent(www.fda.gov) -- approved for use in adults 18 and older.
In addition, the age indication for ID Biomedical Corporation of Quebec's IIV4 vaccine FluLaval Quadrivalent(www.fda.gov) has been expanded from age 3 years and older to age 6 months and older. Children ages 6 through 35 months may be given the same 0.5 mL vaccine dose (containing 15 µg of hemagglutinin [HA] per vaccine virus) that is used for older children and adults.
The MMWR article points out that this expanded licensure creates an additional option for vaccinating children ages 6 through 35 months; previously, the only option available was the 0.25 mL per dose presentation (containing 7.5 µg of HA per vaccine virus) of Sanofi Pasteur's IIV4 vaccine, Fluzone Quadrivalent. Note that if a 0.5 mL single-use vial of Fluzone Quadivalent is used for a child in this age range, only half of the vaccine's volume should be administered, and the other half should be discarded.
The 2017-2018 vaccination recommendations also note that Seqirus' original trivalent Afluria vaccine may be used in patients ages 5 years and older, consistent with its FDA-approved labeling.
Previous guidance regarding first-administration of flu vaccine in children ages 6 months through 8 years still pertains: Evidence from several studies indicates that children this age require two doses of vaccine (administered at least four weeks apart) during their first season of vaccination to achieve optimal protection.
Because pregnant and postpartum women are at increased risk for severe illness and complications from influenza compared with those who are not pregnant, the ACIP recommends that all women who are pregnant or who might be pregnant during flu season be vaccinated. Pregnant women may receive any licensed, recommended, age-appropriate flu vaccine, and the vaccine may be administered at any time during the pregnancy.
Finally, the recommendations note, no one flu vaccine product is preferred over any other among people for whom more than one licensed, recommended product is available.