Merck recalls kids' Hib vaccine due to sterilization problem

Merck & Co., Inc., one of the top seven pharmaceutical companies in the world, announced Wednesday that it has initiated a voluntary recall of 1.2 million doses of a common childhood vaccine due to concerns of potential contamination during the manufacturing process.

The Whitehouse Station, New Jersey-based drug maker, in association with the U.S. Food and Drug Administration and the U.S. Centers for Disease Control and Prevention, has recalled 11 lots of its Haemophilus influenzae type B vaccine, Pedvaxhib and 2 lots of combination Haemophilus influenzae type B hepatitis B vaccine, Comvax.

Yesterday’s recall from US pharmaceutical giant comes after Merck identified a sterilization problem during routine testing of the manufacturing process at a plant in Pennsylvania, where these lots of vaccines were manufactured.

According to Dr. Norman Baylor, director of the FDA's Office of Vaccine Research and Review, the manufacturer of the Hib vaccine found during standard evaluation at the plant potential for microorganisms to have survived equipment sterilization in these lots of the product.

“Merck identified an issue that creates the potential for microorganisms to survive a sterilization step performed during manufacturing," Dr. Baylor said in a joint conference call with the CDC. "No documented contamination of the vaccine has been found."

Merck said that the recall is issued as a precautionary measure as no vaccine-associated health problems have been reported so far. The drug maker also notified that the recall is applicable only to the above mentioned 13 lots of drugs and will not affect any of its other vaccines.

"Right now, this is not a health-threatening situation for children," CDC Director Julie Gerberding, MD, MPH said at a news conference. "We have had no cases of reported injury or adverse events with the Hib vaccine involved in this recall."

Anne Schuchat, MD, director of the CDC's immunization center advised parents not to worry as the recalled vaccines, made by the drug company Merck, are fully potent, and. children who received the vaccines don't need to be revaccinated.

"No product has been found to have bacteria in it, but it is theoretically possible something slipped through," said Schuchat.

Parents whose children recently received the Hib vaccine can look for skin bumps or abscesses at the site of the injection, Schuchat said.

Merck and Sanofi Pasteur are the two American drug manufacturers who provides about half the U.S. supply of Hib vaccine, which has been recommended by the CDC to protect children against meningitis, pneumonia, blood stream and other serious infections since 1990.

The Hib vaccine, which is recommended for all children under 5 years old, with doses starting when children are 2 months old, has significantly reduced the cases of Haemophilus influenzae type b, which can cause bacterial meningitis and pneumonia.

Since the Hib vaccination started annual cases of this disease have gone down from 20,000 to 100 a year. About 14 million doses of the Hib vaccine are given in the United States annually.