February 8, 2011
12 Countries Report Narcolepsy Link To Swine Flu Vaccine
The World Health Organization (WHO) said on Tuesday that twelve countries have reported suspected cases of narcolepsy linked to swine flu vaccinations.
The WHO said in a statement that such sleep disorders had not been seen with vaccines in the past, and were more frequent in Sweden, Finland and Iceland than in other countries.
However, spokeswoman Alison Brunier said that the U.N. health agency decided to keep its advice in favor of vaccination, including with the Pandemrix vaccine highlighted in the study.
Narcolepsy is a sleep disorder that causes extreme fatigue and often results in the patient falling soundly asleep without warning, even during activities.
According to WHO, the Pandemrix vaccine made by GlaxoSmithKline was used in 47 countries around the world during 2009 through 2010 and was included by the agency in donations made to poor nations during the flu pandemic.
Last week, the WHO Global Advisory Committee on Vaccine Safety (GACVS) reviewed data from a Finnish study, which found that children injected with the Pandemrix flu vaccine were nine times more likely to contract narcolepsy than those who were not vaccinated.
"The committee agrees that further investigation is warranted concerning narcolepsy and vaccination against influenza (H1N1) 2009 with Pandemrix and other pandemic H1N1 vaccines," the WHO said.
"An increased risk of narcolepsy has not been observed in association with the use of any vaccines whether against influenza or other diseases in the past," it added.
The European Medicines Agency (EMA) launched a probe into the suspected connection.
"Since August 2010, following widespread use of vaccines against influenza (H1N1) 2009, cases of narcolepsy, especially in children and adolescents, have been reported from at least 12 countries," the WHO added.
Brunier noted that the EMA had not taken any action.
"There's no change to the WHO's current position on use of pandemic influenza vaccines," she added.
"This means that countries should continue vaccinating against H1N1 to immunize persons at risk of severe disease, using monovalent vaccines including Pandemrix if there is no trivalent seasonal vaccine available," she added.
Monovalent vaccines target a single strain of flu while trivalent vaccines, more commonly used every flu season, are effective against three strains.
The preliminary study by Finland's National institute for Health and Welfare (THL) said the most likely explanation of the pattern found in four to 19 year olds was the "joint effect of the vaccine and some other factors."
It also stressed that more investigation was needed.
THL recommended last August of discontinuing its use against H1N1 until it could study the signs of a connection.
On the Net:
- World Health Organization (WHO)
- WHO Global Advisory Committee on Vaccine Safety (GACVS)
- European Medicines Agency (EMA)
- National institute for Health and Welfare (THL)