The popular, needle-free FluMist influenza vaccine had failed to protect kids or adults against flu for years and should not be used this coming flu season, experts said yesterday.
The surprise decision, sure to dismay children and needle-phobes, could also leave paediatricians with a short supply of the vaccine, the Centers for Disease Control and Prevention said.
"Nasal spray flu vaccine accounts for about one-third of all flu vaccines given to children," CDC said in a statement.
Flu vaccines differ from most other vaccines, in the variability of their effectiveness from year to year. They also need to be made fresh each flu season to match circulating strains of influenza, which also changed.
FluMist, made by MedImmune, used live but weakened strains of flu virus to stimulate the immune system. The vaccine which is sprayed up the nose had been reported to be more effective in some seasons than some injected vaccines.
The Advisory Committee on Immunisation Practices, however, reviewed the data from the past few flu seasons and found that it did not work in recent years. In fact, FluMist was only 3 per cent effective last flu season, according to the CDC.
"This 3 percent estimate means no protective benefit could be measured," the CDC said.
"We could find no evidence (the spray) was effective," said Dr Joseph Bresee, a flu expert at the US Centers for Disease Control and Prevention, which presented preliminary study results to the federal advisory committee on immunisation.
According to an AstraZeneca spokesperson, the company was evaluating the committee's recommendation.
FluMist had been, at one time regarded as the best vaccine for protecting children against flu.
Only two years ago, doctors had been advised to use FluMist wherever possible on young children rather than traditional flu- shots.
The performance of all flu vaccines had been poor two winters ago, however, according to data, FluMist performed poorly the two other seasons as well.