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.
Voluntary Non-Safety-Related Recall of Specific Lots of Nasal Spray Vaccine for 2009 H1N1 Influenza
December 22, 2009, 7:00 PM ET
First, it is important to point out that the recall is not safety-related. As part of its quality assurance program, the manufacturer of the nasal spray monovalent 2009 H1N1 flu vaccine, MedImmune, performs routine, ongoing stability testing of the vaccine. Stability testing means measuring the strength (also called potency) of the vaccine over time to make sure it does not go below a pre-specified limit during the vaccine’s “shelf life.” On December 18 and 21, the manufacturer notified CDC and FDA that the potency in 13 batches (called “lots”) of nasal spray vaccine had decreased below the pre-specified limit or were at risk of falling below that limit within the upcoming week. The vaccine was within the specified range at the time the vaccine was distributed. The slight decrease in potency should not affect how the vaccine works. However, the manufacturer will send providers directions for returning any unused vaccine from these lots.
Potency (or strength) is determined by the measurement of the concentration of the active component in the 2009 H1N1 vaccine.
No. There are no safety concerns with these lots of 2009 H1N1 vaccine. All lots successfully passed pre-release testing for safety, purity and potency.
No. The vaccine potency is or will soon be only slightly below the limit. In addition, much of this vaccine has already been administered while fully potent and within specifications. The vaccine in these lots is still expected to be effective in stimulating a protective response. There is no need to re-administer a dose to those who received vaccine from these lots.
Persons who received vaccine from the recalled lots do not need to take any special actions. As is recommended for all 2009 H1N1 vaccines, all children younger than 10 years old should get the recommended two doses of 2009 H1N1 vaccine approximately a month apart for the optimal immune response. Therefore, children younger than 10 years old who have only received one dose of the nasal spray vaccine thus far should still receive a second dose of 2009 H1N1 vaccine. It is best to use the same type of vaccine for the first and second dose.
There were approximately 4.7 million doses in these lots that were distributed to providers. Most of the doses were shipped to vaccine providers in October and early November, during a time when the vaccine potency was still at or above the recommended level. The manufacturer is recalling any doses from these lots that may still be unused.
The voluntary recall described here is specific to the 13 lots of nasal spray 2009 H1N1 flu vaccine noted above. Subsequent lots of the vaccine were produced with a slightly higher potency to decrease the chance that they would fall “below specification” before their expiration dates. As per their routine practice, the manufacturer will continue to monitor the potency of those lots, and will notify healthcare providers if the shelf life of any additional lots is shorter than expected.
This recall does not affect 2009 H1N1 vaccine produced by other manufacturers. However, a similar recall was conducted recently which involved lots of Sanofi Pasteur’s pediatric 2009 H1N1 vaccine in 0.25 mL pre-filled syringes.
Before they were shipped, the lots being recalled now passed all quality controls and met all specifications for safety, purity, and potency.
The manufacturer will send a notification to providers who received doses from any of the 13 lots of vaccine so that they can return any unused vaccine.
Vaccine from these 13 lots was distributed throughout the United States.
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