Tuesday, September 17, 2013
By William K. Alcorn
The 2013-2014 influenza season is here, and with it comes a couple of improvements in the available flu vaccines.
One of the new offerings is a quadrivalent vaccine, which covers four types of flu instead of the traditional three flu strains, said Dr. John Venglarcik, medical director for the Mahoning County District Board of Health.
The quadrivalent vaccines include a second influenza B strain because flu vaccine “failures” in the past have been associated with emergent B strains that were not circulating when the vaccine components were selected in the January before the flu season, Dr. Venglarcik said.
Also new this year, for adults 18 to 49 with egg allergies, is an egg-free version of the vaccine, public health officials said.
While there are some new vaccines available along with the traditional vaccines, age recommendations for getting the vaccine remain the same, Dr. Venglarcik said.
According to the U.S. Centers for Disease Control and Prevention, the influenza vaccine is recommended for everyone 6 months and older.
It is also recommended that children 6 months to 8 years receive two doses upon initial immunization, and that vaccination should be completed by October, he said.
The additional B strain was added not only because of past flu vaccine shortcomings but also because B strains account for a disproportionate share of the morbidity and mortality from influenza in the infant population. Including a second B strain should address this concern, he said.
As a result, the recommended vaccine for people 6 months to 65 is the new quadrivalent vaccines.
For those older than 65, experience with a variety of B strains indicates that age group is not as seriously affected as infants. Therefore, the high-dose vaccine for senior citizens will remain a trivalent preparation, he said.
Dr. Venglarcik offered this technical information to assist physicians in recommending flu shots for their patients.
Influenza strains covered by this year’s United States trivalent are an A/California/7/2009 (H1N1)-like virus, an H3N2 virus antigenically like the cell-propagated prototype virus A/Victoria/361/2011, and a B/Massachusetts/2/2012-like virus.
The new quadrivalent vaccines will include an additional vaccine virus, a B/Brisbane/60/2008-like virus, he said.
The new A quadrivalent inactivated influenza vaccine (Fluzone Quadrivalent [Sanofi Pasteur) will be available in addition to the previous trivalent formulation (which includes a less painful intradermal preparation). Fluzone Quadrivalent is indicated for people 6 months and older.
A quadrivalent live attenuated influenza vaccine (Flumist Quadrivalent [MedImmune]) is expected to replace the trivalent (LAIV3) formulation. FluMist Quadrivalent is indicated for healthy, nonpregnant people 2 through 49 years, Dr. Venglarcik said.