Are H1N1 09 Swine Flu vaccines being recalled and why?

Answer 1

Yes. The Food and Drug Administration (FDA) announced the non-safety recall on December 15, 2009. They determined that the vaccine in a particular lot of pre-filled syringes did not meet the range of potency (strength) that was specified by the FDA and the division of Merck and Company, Inc. for use in the US.

Merck, whose division, Sanofi Pasteur, produced the vaccine, has confirmed that the recall affects 1.2 million doses. The CDC has indicated that only approximately 800,000 of those doses had been distributed. Sanofi Pasteur of Sanofi-Aventis SA, is based in Paris.

According to the Centers for Disease Control and Prevention (CDC) this non-safety issue has prompted the recall of A-H1N1/09 pandemic Swine Flu vaccine that was prepared in single dose syringes for children under age three. These reports indicate that there is no safety issue and those who have already had the vaccination using these particular lots of vaccine do not need to have additional vaccine administered since the strength level is only slightly below what was specified in the original approval by FDA.

In the manufacture of most medicines and vaccines, the recommended dose is based on a specified strength range that will be effective for the general population. Because a larger person may need slightly more and a smaller person slightly less, the exact measure of the recommended dose is adjusted based on clinical trials. These trials are used to determine the parameters of the dosage that can be effective for larger sized people, but still safe and not too much for the smaller sized people. In some types of medicines this dose must be more exact and then it is often based on the size of person, such as doses specified as so many milligrams or units per kilogram of weight.

The doses of vaccines do not need to be as specific. But when the FDA has approved and expected delivery of a specific dose that will be safe and effective for the general population, instead of one which needs to be more finely adjusted by individual measurements, they will require the recall and expect the company to provide the drug exactly as stated in the approval documents.

This is an indication that the ongoing monitoring of the H1N1/09 vaccine by the FDA is being carried out well and that the watch is especially close. The recall is a reassuring indicator about the monitoring process to medical professionals .

Only certain lots of the vaccine are included in the recall of December 15, 2009.

The following statements were made by CDC on their web site [see link below]:

Should infants and children who received vaccines from these lots be revaccinated?


No. The vaccine potency is only slightly below the "specified" range. The vaccine in these lots is still expected to be effective in stimulating a protective response despite this slight reduction in the concentration of antigen. There is no need to re-administer a dose to those who received vaccine from these lots. However, as is recommended for all 2009 H1N1 vaccines, all children less than 10 years old should get the recommended two doses of H1N1 vaccine approximately a month apart for the optimal immune response. Therefore, children less than 10 years old who have only received one dose of vaccine thus far should still receive a second dose of 2009 H1N1 vaccine.

What action(s) should parents of children who have received vaccine from the recalled lots take?
Parents of children who received vaccine from the recalled lots do not need to take any action, other than to complete the two-dose immunization series if not already completed.
CDC has indicated that the following lots are included in the recall:


0.25 ml pre-filled syringes, 10-packs (NDC # 49281-650-25, sometimes coded as 49281-0650-25):
UT023DA
UT028DA
UT028CB


0.25 ml pre-filled syringes, 25-packs (NDC # 49281-650-70, sometimes coded as 49281-0650-70):
UT030CA