Flu vaccine recall has little effect on vaccination efforts against the H1N1 flu

This week’s recall of four batches of flu vaccine will have little effect on efforts to vaccinate Missourians against the H1N1 flu because adequate alternative supplies of the vaccine are now available, state health officials said.

Vaccine maker Sanofi-Pasteur voluntarily recalled some 800,000 doses of vaccine designed for children because testing showed that the vaccine in four production groups had lost strength after it was packaged. The vaccine remained safe, but no longer met potency standards.

Health officials said the vaccine was still potent enough to give children immunity. But it was recalled as a precaution while vaccine makers tried to determine the reason that those vaccine batches were losing effectiveness. The recall involves certain batches made without preservative.

Margaret Donnelly, director of the Department of Health and Senior Services, said the recall showed the extraordinary lengths that vaccine makers and regulators are taking to ensure the effectiveness of the H1N1 flu vaccine. The vaccine had adequate strength before it was packaged. But later tests on the packaged version showed that some batches had a small decrease in strength, she said.

“Vaccine makers repeatedly test their products to ensure that they remain safe and strong enough to cause the body to develop immunity to the flu virus,” Donnelly said. “These vaccines still remained potent enough to protect children against the H1N1 flu. But they no longer met the very high standard set by the federal government. Therefore, they are being recalled and replaced.”

The recall involves only pre-filled syringes of vaccine designed for children under three years old. Children who received the vaccine will still be protected, health officials said, because the decrease in potency was so small.

In addition, all children less than 10 years old need to get two doses of vaccine to achieve the immunity that adults and older children develop with one dose. The first dose primes the child’s immune system and the second, given 28 days later, causes the body to develop immunity.

Health officials said children would be protected even if they received two doses of the vaccine subject to a recall because the lower-potency vaccine is still strong enough to create immunity. All parents, including those whose children might have received the lower-potency vaccine, should make sure that their children under 10 receive a second dose of vaccine.

Missouri received 22,200 doses of the vaccine now subject to the recall. Those doses were shipped last month to about 75 counties throughout the state. Sanofi-Pasteur will send health care providers directions for returning unused vaccine from the affected batches.

For more information about the H1N1 flu, check out the health department’s web site at http://www.dhss.mo.gov/missouriflu/_H1N1Flu.html.

To find flu vaccination clinics scheduled in your area, go to http://www.dhss.mo.gov/missouriflu/_provider_listing.html and click on your county.