February 18, 2010
About 12 million doses of monovalent H1N1 influenza in pre-filled syringes from Sanofi Pasteur have a shorter shelf life than indicated on the label.

There are no safety concerns with the vaccine. Patients who received vaccine from these lots do not need to be revaccinated, according to a February 3 health update from the Centers for Disease Control and Prevention (CDC).

The 50 lots affected were shipped from November 2009 to January 2010. Any left over supplies should be used by Feb. 15 to ensure potency. Vaccine not used by that date should be discarded or returned for disposal to Sanofi Pasteur Inc., c/o Capital Returns, 6101 N. 64th St., Milwaukee, WI 53218.

Sanofi's 2009 H1N1 vaccine in multi-dose vials are not affected.

In January and December, both Sanofi Pasteur and MedImmune issued nonsafety-related recalls of selected lots of H1N1 vaccine after noticing diminished potency.

For more information on the current update, including vaccine lot numbers, read the CDC health update.