However, the Minister said the swine flu vaccination programme would continue. In her view, Risikko thought it wise to examine any connection between narcolepsy and swine flu vaccine in other European countries.

The National Institute for Health and Welfare (THL) is to determine if vaccine for the H1N1 swine flu could be linked to an increase in cases of narcolepsy among children.

The condition causes excessive daytime sleepiness even after adequate nocturnal sleep.

Although the THL’s Vaccine Department Director Terhi Kilpi does not fear any connection between the H1N1 jab and narcolepsy, she says doubts must be examined.

Experts on both vaccines and narcolepsy met on Wednesday to discuss the issue.

Doubts arose when a Finnish child neurologist noticed an increased level in the number of narcolepsy cases this year. Similar observations have been noticed in Sweden, reports the tabloid Iltalehti.

Medical officials in Sweden are also examining a possible link between the Pandemrix vaccine and narcolepsy, according to the newspaper Svenska Dagbladet. The Swedish news agency TT reports six cases with a possible link to the vaccine.

A patient suffering from narcolepsy may suddenly fall asleep, for example, while, speaking or eating without prior warning. Their muscles may also suddenly weaken, causing them to suddenly collapse. There is no known cure for the disease.

Several Times Normal Rate of Cases

About a dozen Finnish children fell ill with narcolepsy during or after last winter's swine flu epidemic, far more than the average rate. The THL is trying to determine whether the cases may have been related to the H1N1 vaccine or to the flu itself.

The cases were diagnosed during the spring and early summer. Dr Markku Partinen, a docent in neurology at the University of Helsinki and former president of the World Association of Sleep Medicine, notes that the cases appear to have a chronological link to the H1N1 epidemic.

Doctors began to wonder when an unusually large number of cases of narcolepsy began to appear last spring.

“When it became clear that the symptoms began to appear in December, January and February, we began to consider a link to the swine flu epidemic,” says Partinen.

So far about 12-14 cases have been detected, all with symptoms that began between December and February, says Partinen. The patients are aged 5 to 15.

On average about three cases of the illness are diagnosed in Finland annually.