According to the latest Swedish study, which is in line with the Finnish findings, about 3 in every 100,000 children and young people vaccinated with Pandemrix may develop narcolepsy, reports news agency TT.
There was no increased risk for adults that took the vaccine. Researchers emphasise that much more research is needed, however, and over a longer timespan to see the full effects of the vaccine, and if indeed it is the vaccine that is the culprit, and not some other environmental factor. Other international studies haven't revealed any such link.
Narcolepsy is a chronic neurological illness which can cause drowsiness and sleep during the day as well as sleep disorders at night. It can also involve sudden but temporary loss of muscular control.
Emily Olsson, who is twelve and recently developed the illness, told Swedish TV news it is not just the fact that she is tired that is difficult, but she is scared to sleep at night. She is also worried about her school work, saying she has always been a good student, but is now worried that the sickness will make life at school much more difficult, and mean she gets worse grades than she otherwise would have got. "My whole life has gotten worse", she says, "it's been ruined".