The drug company Merck told the US Centers for Disease Control and Prevention (CDC) yesterday, Wednesday 12th December, that it is recalling over one million doses of vaccines routinely given to babies and children. The drug company said it was recalling 10 lots of PedvaxHIB vaccine and 2 lots of Comvax vaccine because they could not assure product sterility.

During a routine standard check on manufacturing equipment used in making the two vaccines, the manufacturer said they found signs of a bacteria called Bacillus cereus. However, when samples of the vaccines were tested before shipment, no such contamination was found. The voluntary recall is purely a precaution, said Merck.

According to the CDC, the vaccines affected are:

Vaccine Lot Expires On
PedvaxHIB0677U11 January 2010
PedvaxHIB0820U12 January 2010
PedvaxHIB0995U16 January 2010
PedvaxHIB1164U18 January 2010
PedvaxHIB0259U17 October 2009
PedvaxHIB0435U18 October 2009
PedvaxHIB0436U19 October 2009
PedvaxHIB0437U19 October 2009
PedvaxHIB0819U09 January 2010
PedvaxHIB1167U10 January 2010
COMVAX0376U05 January 2010
COMVAX0377U08 January 2010

Both types of vaccine protect against Hib and other conditions. Hib is short for Haemophilus influenzae type b, a serious disease caused by a bacteria that usually strikes children under 5 years old. Comvax also protects against hepatitis B.

According to the Associated Press, Merck produces about half of the US annual supply of Hib vaccine.

Government health officials from the CDC and the US Food and Drug Administration (FDA) said in a press teleconference the recall was a precaution and posed no threat to babies and children. The first shot of Hib vaccine is given routinely to babies as young as two months.

In a way the possibility of this recall was forewarned. Last month, Merck reported to the CDC that their “PedvaxHIB vaccine would be unavailable for shipment pending the results of production quality tests”, according to a statement on the CDC website. The vaccine would become available again early 2008, but the “exact timing would be dependent on resolution of a manufacturing issue”.

The Chicago Tribune reported that federal officials said they had no idea how many of the over one million doses had already been given to children.

The CDC said Merck had assured them there were no reports of “abscesses or disseminated B. cereus infection in children who received vaccines from affected lots”. The CDC said the Vaccine Adverse Event Reporting System (VAERS) had also not detected any problems in connection with the vaccines affected by this recall.

If a child were to receive a vaccine that was infected with “B. cereus or microorganisms, there may be a risk of developing localized or disseminated infections”, said the CDC. Children with compromised immune systems may experience more serious symptoms. The infections would occur within one week of the vaccination.

In other words, if your child has just had a Hib shot that later is found to have been contaminated, the federal agencies are saying they don’t think this will cause more than a minor skin irritation around the area, and this will happen up to one week later. But the infection could be worse for children with weak immune systems.

Click here for Health Care Provider Questions and Answers about the recall (CDC).

Written by: Catharine Paddock