On December 12, 2007, Merck announced the recall of 1.2 million doses of its vaccine Hib. The vaccine is given to infants and toddlers to fight against pneumonia, meningitis, and upper respiratory infections. Merck' recall covers eleven lots of its Hib vaccine and two lots of its Comvax vaccine after routine testing detected a contamination problem at its facility in Pennsylvania. The company states it "cannot assure sterility of those specific vaccine lots."

Vaccine Lots Affected by Merck Recall and CDC Recommendations

According to the Centers for Disease Control' (CDC) website, www.cdc.gov/, the following U.S. lots (organized by product description, lot #, and expiration date) are affected:

PedvaxHIB® 0677U 11 January 2010

PedvaxHIB® 0820U 12 January 2010

PedvaxHIB® 0995U 16 January 2010

PedvaxHIB® 1164U 18 January 2010

PedvaxHIB® 0259U 17 October 2009

PedvaxHIB® 0435U 18 October 2009

PedvaxHIB® 0436U 19 October 2009

PedvaxHIB® 0437U 19 October 2009

PedvaxHIB® 0819U 09 January 2010

PedvaxHIB® 1167U 10 January 2010

COMVAX® 0376U 05 January 2010

COMVAX® 0377U 08 January 2010

Another lot of PedvaxHib was recalled, but it was only used in China.

No Injury Reports Thus Far from Recalled Vaccines

Merck states no contamination has been found in any of the vaccines themselves. The company also maintains there have been no reports of any harm to children thus far. However, because the sterility of its vaccine "cannot be assured," the CDC cautions there is a risk that children may develop localized or disseminated infections.

Signs to Watch For

The CDC recommends that parents of children with the affected vaccine should watch for signs of infection (ie., redness and swelling at the infection site). The CDC is monitoring the affected vaccines by reviewing adverse event reports received by the Vaccine Adverse Event Reporting System (VAERS). VAERS is a nationally passive reporting system that accepts and monitors reports of adverse events following vaccination.

Vaccine Shortage and Impact on Disease

Because of the recall, many health care providers who only use Merck Hib may have little if any supplies of non-recalled vaccines. The other U.S. vaccine manufacturer, sanofi pasteur, is likely unable to immediately provide adequate Hib vaccine to fully vaccinate children. The CDC recommends that providers temporarily defer administration of the routine Hib vaccine booster dose given at 12-15 months except for children in specific high risk groups. The CDC reports it will continue to monitor the supply of available Hib vaccines and work closely with vaccine manufacturers "to equitably distribute vaccine to meet immediate needs."

Current immunization rates in the U.S. are high. As a result, there has been a substantial decline in the transmission of bacteria (though it has not been completely eliminated). When immunization rates decline, children are more susceptible to diseases. The CDC has assured the public they are taking the vaccine recall and shortage "very seriously."

CDC Recommendations to Doctors and Parents

Children already vaccinated with the affected lots do not have to be revaccinated and are protected, said CDC director Anne Schuchat. However, the CDC says doctors should not use the vaccine from the affected lots and should complete the vaccination series for children already started with the non-affected vaccine.

Posted by: Jason M. Kroot of Kroot Law, LLC