Content on this page was developed during the 2009-2010 H1N1 pandemic and has not been updated.
- The H1N1 virus that caused that pandemic is now a regular human flu virus and continues to circulate seasonally worldwide.
- The English language content on this website is being archived for historic and reference purposes only.
- For current, updated information on seasonal flu, including information about H1N1, see the CDC Seasonal Flu website.
Q&A for parents: recall of some batches of children’s 2009 H1N1 flu vaccine:
December 18, 2009, 5:00 PM ET
Vaccines are tested both before and after they are sent out to be used. During a routine stability check, some of the lots of vaccine were found to have fallen below specific requirements for strength (or potency). This means that the amount of active ingredient in the vaccine that prompt the body to develop immunity had decreased. However, the decrease was small and should not affect the immune response of children that received the reduced potency vaccine.
This recall is not related to the safety of the vaccines. There is no safety issue with any of the recalled lots.
If your child got a second dose using this vaccine, he or she is considered adequately vaccinated. There is no need for them to get another dose. The strength of the vaccine was only slightly less than the acceptable standard, will be enough to get a full immune response. Your child’s immune system will still make antibodies (protection) against H1N1 influenza virus. This is true even if both shots came from a recalled lot. With the coverage of two shots, children will make the immune response they need.
A. The vaccine was shipped to doctors throughout the U.S. The manufacturer is working with doctors and others who give vaccines to make sure that the people who give the vaccines stop using those lots.
You do not need to call your pediatrician or health department to find out if your child got this vaccine. You do not need to take further action, unless your child needs his or her second dose of 2009 H1N1 vaccine. Your child is still considered vaccinated even if vaccinated with vaccine from a recalled lot.
However, another company makes injectable vaccine for this age group, including vaccine in multi-dose vials that contain traces of preservative (including thimerosal) to prevent contamination from bacteria or fungus. This vaccine is safe for children older than six months. It has been given to thousands of children safely.
For healthy children 24 months (2 years) and older, the nasal spray vaccine is also available and safe. It does not contain any preservatives. Children who have a history of wheezing, asthma, or a medical condition such as diabetes, should only receive the shot, not the nasal spray. If you have questions about what kind of vaccine your child can get, talk to your child’s doctor or nurse.
For more information about preservatives and vaccine safety, click here: "General Questions and Answers on Thimerosal" "Why it's Important to Monitor Vaccine Safety"
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