More than 4.6 million doses of H1N1 influenza (swine flu) nasal spray vaccines have been recalled due to loss of potency, the second such vaccine recall this month. However, the U.S. Centers for Disease Control and Prevention (CDC) indicates that there are no safety concerns and individuals who received vaccines from these lots do not need to be revaccinated.
The swine flu vaccine recall was announced this week by MedImmune, a Maryland subsidiary of AstraZeneca PLC. The recall affects 13 lots of the nasal spray vaccine, but the majority of those vaccines have already been used, according to the FDA.
There is no health risk associated with the recalled vaccines, and although the potency has declined, federal regulators say that the strength of the vaccines is still within acceptable levels.
“The slight decrease in potency should not affect how the vaccine works,” the CDC announced in a statement. “There are no safety concerns with these lots of 2009 H1N1 vaccine. All lots successfully passed pre-release testing for safety, purity and potency.”
MedImmune is the only manufacturer of the nasal spray version of the vaccine, which can be used on healthy people from ages 2 through 49. Company officials say that quality control testing indicated a loss of strength over time, leading to a recall of 13 lots. The doses were designed to have a four-month shelf life. The FDA has approved 62 lots of MedImmune nasal spray vaccines, which the agency and the manufacturer say all met potency standards when first released.
Earlier this month, about 800,000 H1N1 vaccine injections for children were recalled by Sanofi Pasteur, also due to a loss of strength. As with the MedImmune recall, there is no associated health risk and children who received the vaccine do not need to be revaccinated. However, the CDC reminded parents that all children under the age of 10 need to get two shots to be fully vaccinated.