Hib Vaccine Still in Short Supply Following Merck Vaccine RecallJan 10, 2008 | Parker Waichman LLP Last month, Merck & Co. Inc. recalled about 1.2 million doses of vaccines—11 lots of PedvaxHIB vaccine and two lots of Comvax vaccine—when quality control checks revealed production equipment might not have been properly sterilized. The vaccines involved protect against Hib—or Haemophilus influenzae type b—disease and other conditions; Comvax also prevents against hepatitis B. Because of the vaccine recall, there is a shortage on both brands of the Hib vaccines nationwide and those wishing vaccines will likely have to wait until year-end.
Hib is a bacterium that can cause a serious form of pneumonia and a condition called bacterial meningitis; Hib was the leading cause of bacterial meningitis in children under five years of age, according to the US Centers for Disease Control and Prevention (CDC). “From the Merck perspective, we hope to be able to return Pedvax and COMVAX to the supply in the fall of this year," Mary Elizabeth Blake, a Merck spokeswoman, said yesterday.
The vaccines were manufactured in West Point, Pennsylvania and distributed beginning April 2007. All but one lot was distributed in the United States, the company said, adding that the potential for contamination of any individual vaccine is low—and—if present, the contamination level would be low. Sterility tests of the recalled vaccine lots did not reveal any contamination, according to Merck, saying the recall does not affect other vaccines it manufactures. Children who received the affected vaccine need not be re-vaccinated as efficacy was not compromised, according to the CDC's National Center for Immunization and Respiratory Diseases.
Merck and the CDC jointly announced the recall last month. Until Merck is able to return to full production, the CDC will assist by doling out some of their supply—approximately 750,000 doses. The CDC is also working with Sanofi-Pasteur, the only other licensed manufacturer of Hib vaccine, to increase supplies. Many doctors, who do not have enough stock, feel the Sanofi Pasteur stock is not adequate. The CDC is also recommending that parents delay boosters and available supplies are being directed to infants in need of initial shots. The agency recommends booster doses for children at high risk for Hib infection and includes American Indian children; Alaska native children; and children with sickle cell disease, HIV, immunodeficiency conditions, and certain cancers. Dr. Anne Schuchat, director of the CDC's National Center for Immunization and Respiratory Diseases, said last month that 14 million doses of Hib vaccine are needed nationwide to meet the recommended immunizations for infants and toddlers.
Merck supplies about half the 14 million doses of Hib vaccine used in the U.S. annually. It said that in addition to the doses recalled—roughly four months worth of production—it quarantined nearly a year’s worth of other, possibly suspect doses, and doesn’t expect to supply any more until at least this October. That means roughly two years of normal production is unavailable.
The CDC said before the vaccine was introduced in the mid-1980s, there were about 20,000 U.S. cases a year of invasive Hib, which can cause brain damage, deafness, and death.