Interim recommendations for the use of Haemophilus influenzae type b (Hib) conjugate vaccines related to the recall of certain lots of Hib-containing vaccines (PedvaxHIB and Comvax).

On December 13, 2007, Merck & Co., Inc. (West Point, Pennsylvania) announced a voluntary recall of certain lots of two Haemophilus influenzae type b (Hib) conjugate vaccines, PedvaxHIB (monovalent Hib vaccine) and Comvax(R) (Hib/hepatitis B vaccine). Providers should return unused vaccine from these recalled lots using procedures outlined on the Merck website at http://www.merckvaccines.com/PCHRecall.pdf. Additional information regarding the affected lots is available online from the Food and Drug Administration (FDA) at http://www.fda.gov/consumer/updates/hib121307.html. Merck has suspended production of its Hib conjugate vaccines and does not expect to resume distribution of these vaccines until the fourth quarter of 2008. The recall of PedvaxHIB and Comvax and suspension of production are expected to result in short-term disruption to the Hib vaccine supply in the United States.