Manufacturer Recalls 800,000 Doses of H1N1 Vaccine; Flu Experts Not Worried

Dec. 15, 2009— -- No big deal. That's what infectious disease experts are saying about drugmaker Sanofi Pasteur's recall of about 800,000 pediatric doses of its vaccine against pandemic H1N1 influenza because of low potency. The recall was announced by the U.S. Centers for Disease Control and Prevention on Tuesday.

"It is a pain the neck, but not a major crisis," said Dr. William Schaffner, chair of Vanderbilt University School of Medicine's Department of Preventive Medicine in Nashville, Tenn. "This should not discourage people from being vaccinated."

But the recall is hardly a shot in the arm for a swine flu vaccination effort that has in recent months been plagued by delays and supply shortages.

"I suspect most of the consequences will be perceptual," said Stephen Morse, professor in the Department of Epidemiology at the Columbia University Mailman School of Public Health in New York."But it does add to the embarrassment in a program whose glitches have already been well publicized."

Despite the nature of the recall, children who were vaccinated with the weakened doses should not be revaccinated because the antigen content "is only slightly below the 'specified' range," according to the CDC. In other words, even the weakened level of the vaccine is still expected to be protective.

The recall does not affect any of the vaccine for adults or products from other manufacturers. And according to the CDC, "There are no safety concerns with these lots of H1N1 vaccine. All lots successfully passed pre-release testing for purity, potency, and safety." The strength of vaccines can sometimes decline with time, the agency said in a statement on its Web site.

The weakened potency of the vaccine doses was identified by Sanofi Pasteur during routine quality assurance testing, but the company has not yet determined the cause. Representatives from the company were not immediately available for comment.