Infant Flu Shot Seizure Reports Being Investigated by FDA and CDC

Federal investigators are looking into a surge of infant seizures being reported in connection to the Sanofi-Aventis Fluzone flu shot. 

On January 20, the FDA and the U.S. Centers for Disease Control and Prevention (CDC) reported that there has been an increase in the number of febrile seizures reported in children under 2 years of age who were given the Fluzone flu shot. The agencies have announced they are investigating the reports, which were submitted through the Vaccine Adverse Event Reporting System.

The seizures appear to be caused by high fevers which developed after the infants were given a shot of Fluzone, which is a trivalent inactivated influenza vaccine (TIV) made by Sanofi Pasteur, Inc., the vaccine division of Sanofi-Aventis.

The FDA and CDC investigation will seek to determine whether there is a direct link between the vaccine and the seizures and what action should be taken.

Fluzone is the only flu shot available for children from 6 months to two years old for the 2010-2011 flu season. The agencies stressed that there have been no other observed increases in seizures related to any other flu shots or in any other age category. The CDC still recommend the use of the vaccine in everyone above the age of 6 months.

The FDA and CDC said the seizures appear to be rare, and typically the children suffer no long-term effects, even though they can be frightening for parents and caregivers. Febrile seizures occur in about 4% of children between the ages of six months and five years old and can be caused by anything that causes a fever, including ear infections, colds, the flu, viral infections and flu shots.

The agencies report that one study found that about 1% of children under 5 suffered seizures after receiving the flu shot, compared to 9% who were hospitalized due to an actual influenza viral infection.