CDC publishes ACIP 2015-2016 influenza vaccine guidelines

The CDC’s Advisory Committee on Immunization Practices published updated influenza vaccination recommendations for the 2015-2016 influenza season in a recent MMWR.

According to the report, the formula composition for 2015-2016 trivalent vaccine includes hemagglutinin (HA) derived from an A/California/7/2009 (H1N1)-like virus, an A/Switzerland/9715293/2013 (H3N2)-like virus, and a B/Phuket/3073/2013-like (Yamagata lineage) virus. These vaccines will be included in quadrivalent influenza vaccines, along with a B/Brisbane/60/2008-like (Victoria lineage) virus.

Population recommendations

During a Feb. 26 meeting, the ACIP unanimously voted in favor of annual influenza vaccinations in all people aged 6 months and older without contraindications. The report recommends children aged 6 months to 8 years receive the first dose as soon as possible and the second dose at least 4 weeks later.

However, with respect to the consistent A(H1N1) virus circulation since 2009 and the introduction of an A/California/7/2009(H1N1)-like virus in 2010, separate vaccinations with the virus are no longer recommended in children aged 6 to 8 years. The ACIP recommends that children who received two or more doses of trivalent or quadrivalent vaccine in seasons prior to July 2015 only need a single dose.

In older populations at least 65 years of age, previous findings showed that antibody levels induced by vaccine declined 6 months after vaccination. However, the committee wrote that delaying vaccination could result in missed opportunities.

“Vaccination programs should balance maximizing the likelihood of persistence of vaccine-induced protection through the season with avoiding missed opportunities to vaccinate or vaccinating after influenza virus circulation begins,” they wrote.

Vaccination with h istory of egg allergy

Recent data demonstrated that influenza vaccines did not trigger allergic reactions in patients with a history of egg allergy, and inactivated influenza vaccines (IIVs) with as much as 0.7 g/0.5 mL were tolerated, the researchers wrote. However, limited data are available on the use of live attenuated influenza vaccine (LAIV) in patients with egg allergy histories.

Researchers estimated a 1.3% incidence rate of systemic allergic reaction including anaphylaxis in children administered LAIV. Therefore, IIV or RIV3 vaccines are recommended in these populations. Physicians familiar with manifestations of egg allergy should administer IIV vaccines and observe patients for 30 minutes or longer. Any severe allergic reaction should be considered a contraindication to future vaccinations, according to the report.

LAIV vs . IIV

In light of conflicting and limited data indicating that LAIV is more efficacious than IIV, the committee retracted the suggestion of administering LAIV over IIV in patients aged 2 to 49 years. Other recommendations in the report state LAIV should not be administered to patients less than 2 years or greater than 49 years of age, pregnant women, immunocompromised patients, children with contraindications detailed in the package insert, patients with an egg allergy, children with asthma aged 2 to 4 years, and patients who consumed influenza antiviral medications within 48 hours of administration.

Product approvals

The report also listed new and updated vaccine products recently approved by the FDA, which included:

the administration of Afluria (bioCSL) using the Stratis needle-free jet injector (PharmaJet.), a reusable spring-powered device, in patients aged 18 to 64 years;

the expanded use of Flublok (RIV3, Protein Sciences) in patients aged 50 years and older (previously approved in patients aged 18 to 49 years); and

the modified formulation of Fluzone Intradermal Quadrivalent (Sanofi Pasteur) in patients aged 18 to 64 years.

Disclosure: The researchers report no relevant financial disclosures.