The US Advisory Committee on Immunisation Practices did not want children aged nine and below to get the Afluria shot, the U.S. version of CSL's Fluvax, as the vaccine cause fibrile convulsion. The committee advised that Afluria can only be used if there are no alternative vaccines available or if a child has a higher risk of complications from influenza.

In Europe, the ban on the CSL seasonal flu vaccine applies to children aged five and below.

The bans follow the suspension in April of the use of Fluvax on under-five Australians because the shot causes fever fits at nine times the normal rate. A Brisbane toddler had died within hours of taking the seasonal flu jab prompting a government investigation of the vaccine's side effects.

CSL's Fluvax is the only vaccine in the world that combines seasonal and swine flu strains. It is approved by the World Health Organisation.