# 2789
Lisa Schnirring of CIDRAP News has the details on today's release of the World Health Organization's recommendations for next fall's northern hemisphere flu shots.
Since there's nothing I could possibly do to improve on Lisa's report, I'll just post the first couple of paragraphs and then get out of the way.
Follow the link to read her report in its entirety.
WHO picks new B strain for 2009-10 flu vaccine
Lisa Schnirring
Staff Writer
Feb 13, 2009 (CIDRAP News) – Because of a suboptimal match between the this year's flu vaccine and circulating influenza B viruses, the World Health Organization (WHO) has recommended changing one of the three strains used in flu vaccines for the Northern Hemisphere next fall and winter.
The WHO's choices for the two influenza A strains remain the same as last year, according to new reports published on the WHO Web site this week. The agency recommended keeping the influenza A/H1N1 and A/H3N2 variants used in this year's vaccine, both of which are labeled Brisbane strains.
The influenza B component of this year's flu vaccine was from the Yamagata lineage, but the proportion of strains from the Victoria lineage continues to increase and has become predominant in many countries, the WHO said. The US Centers for Disease Control and Prevention's most recent flu surveillance report, for the week of Feb 1 through 7, said that of 78 influenza B viruses that were characterized, 55 belonged to the Victoria lineage.
Health officials in the United States have discussed including both lineages in the seasonal vaccine to address the unpredictable prevalence of the influenza B strains, especially since a vaccine against one lineage offers little protection against the other.
