# 5321
After consultations this week with public health officials, researchers, and pharmaceutical companies the World Health Organization has released their recommendation for the antigen composition of this fall’s trivalent flu vaccine.
Recommended composition of influenza virus vaccines for use in the 2011-2012 northern hemisphere influenza season
It is recommended that vaccines for use in the 2011-2012 influenza season (northern hemisphere) contain the following:
- an A/California/7/2009 (H1N1)-like virus;
- an A/Perth/16/2009 (H3N2)-like virus;
- a B/Brisbane/60/2008-like virus.
If this list looks familiar, it’s because this is the same mixture the WHO recommended for last fall’s flu shot, and the one to be used over the coming months in the southern hemisphere.
The WHO also posted a full report with their rationale for each strain selection which you can access at:
The short version is: while minor variations have been observed in both the 2009 H1N1 and the seasonal H3N2 viruses over the past year, HI (Hemagglutination inhibition) testing of isolates suggest that the vast majority remain antigenically indistinguishable from the recommended strains.
Lisa Schnirring, writing for CIDRAP, has a nice summation of today’s report, along with information about new H5N1 vaccine candidates.
WHO sticks with current strains for next flu vaccine
Lisa Schnirring Staff Writer
Feb 17, 2011 (CIDRAP News) – Signaling that the current flu strains are likely to persist over the next several months, the World Health Organization (WHO) today recommended sticking with the current trio of vaccine strains for the Northern Hemisphere's next influenza season.