The TGA said an investigation led by Nobel laureate Peter Doherty had not found a conclusive cause of the convulsions.
But the "current working hypothesis" was that the strain of swine flu used in this year's seasonal flu vaccine appeared to contain a higher than usual level of a protein called neuraminidase.
"Excess neuraminidase enzyme activity may be pyrogenic (producing fever) and may thus be contributing to the increase in febrile reactions in young children receiving the vaccine for the first time," the TGA said.
read more here:
http://www.theaustralian.com.au/news/nation/cause-of-vaccine-convulsions-remains-a-mystery/story-e6frg6nf-1225943922526
