Putting you to sleep…
AFP – A study in England has strengthened evidence from Scandinavia that a vaccine used to prevent pandemic flu boosted the risk of sleep disorder among teens and children, doctors said on Tuesday.
Using the Pandemrix vaccine increased the risk of narcolepsy among people aged four to 18 by a factor of 14 compared to those who did not get the jab, they said.
The risk in absolute terms was between one in 52,000 people and one in 57,000, but this figure may be an over-estimate, according to the study published by the British Medical Journal (BMJ).
Narcolepsy is a chronic disorder of the nervous system that causes excessive drowsiness, often causing people to fall asleep uncontrollably.
It normally occurs among 25-50 of every 100,000 people, although figures are sketchy, the study said.
Pandemrix was the main vaccine used to fight the 2009-2010 outbreak of H1N1 “swine” flu, a much-feared pandemic involving a novel strain influenza virus.
The bug turned out to be as dangerous as normal “seasonal” flu, a discovery prompting some accusations that health watchdogs had over-reacted.
Last September, the European Centre for Disease Prevention and Control (ECDC) said that, on the basis of evidence from sleep centres in Finland and Sweden, vaccination for H1N1 among teenagers and children had led to a narcolepsy risk of one in 20,000.
The new research conducted in England suggests that data from the two Scandinavian countries were not a freak result, the study said.
Pandemrix uses an adjuvant, or booster, called AS03, which aims to strengthen the immune response to the H1N1 virus.