# 4613
About six weeks ago we began seeing reports of an unexpected number of adverse side effects among children under the age of 5 who had received CSL Ltd. Fluvax seasonal flu vaccine.
The total number or reports were small (several hundred) out of thousands of shots given, but significantly higher than normal.
Most of the side effects were related to fever, with some children experiencing febrile convulsions. Others experienced nausea and vomiting, or injection site inflammation (see Australia Investigating Adverse Vaccine Reactions).
Within days, doctors were advised to suspend giving the shots pending an investigation. No causative agent has been identified, but the company has decided to `retrieve’ all unused doses of the vaccine.
CSL’s Fluvax is the first seasonal vaccine to contain the novel (pandemic) H1N1 antigen along with the new H3N2 antigen and a `B’ influenza component.
The monovalent (single antigen) panvax shot for novel H1N1 did not produce these sorts of reactions, and is being recommended for children in Australia instead.
Flu vaccines have historically been very safe, and so why this particular formulation should have produced this level of febrile reactions in young children is a bit of a mystery.
One that scientists, no doubt, will continue to be looking at over the summer.
This from Bloomberg Businessweek. A hat tip to RoRo on FluTrackers for this link.
CSL Recalls Flu Shot as Side Effects Rise Nine-Fold (Update1)
June 01, 2010, 6:22 AM EDT
By Simeon Bennett
June 1 (Bloomberg) -- CSL Ltd., the Southern Hemisphere’s only flu vaccine maker, recalled its seasonal shot for children in Australia after investigations failed to explain a nine-fold increase in fever and convulsions.
CSL is voluntarily withdrawing unused doses of its Fluvax Junior shot from clinics and distributors, the Melbourne-based company said in a statement today. Jim Bishop, Australia’s chief medical officer, said vaccinations should continue to be suspended for children under 5 years, a recommendation initially made on April 23.
Fluvax was linked to febrile convulsions in about 9 children in every 1,000 who got the shot, higher than the expected rate of 1 per 1,000, Bishop said in a separate statement. It’s unclear whether Sanofi-Aventis SA’s Vaxigrip and Solvay SA’s Influvac caused similar side effects because insufficient doses have been used in Australia, he said.
