The  US Food and Drug Administration has approved this year’s seasonal influenza  vaccines that include new strains of the virus likely to cause the flu in the US during the  2008–2009 season.

  The  six vaccines and their manufacturers are: CSL Limited, Afluria; GlaxoSmithKline  Biologicals, Fluarix; ID Biomedical Corporation of Quebec, FluLaval; MedImmune Vaccines Inc.,  FluMist; Novartis Vaccines and Diagnostics Limited, Fluvirin; and Sanofi  Pasteur Inc., Fluzone.

  This  season’s vaccines contain three strains of the influenza virus that disease  experts expect to be the most likely cause of the flu in the US. The FDA  changed all three strains for this year’s influenza vaccine-an unusual  occurrence, because usually only one or two strains are updated from year to  year. Of note, two of the three strains recommended for the US this year  are now in use for the southern hemisphere’s 2008 influenza season, which is  currently underway.

  Every  season’s vaccines are modified to reflect the virus strains most likely to be  circulating. Each year, experts from the FDA, World Health Organization, US  Centers for Disease Control and Prevention (CDC), and other institutions study  virus samples and patterns collected throughout the year from around the world  in an effort to identify strains that may cause the most illness in the  upcoming season. Based on those forecasts, the FDA decides each February on the  three strains that manufacturers should include in their vaccines for the US population.  This decision is made early in the year so that manufacturers have enough time  to produce the new vaccines.

  Approval  information and specific indications can be found on the 

News

The US Food and Drug Administration has approved this year’s seasonal influenza vaccines that include new strains of the virus likely to cause the flu in the US during the 2008–2009 season.