The World Health Organisation said on Tuesday that it was looking at a mutation of the A/H1N1 flu virus recently detected in several countries and regions “very carefully” to see whether it causes severe diseases.

So far, there was still no evidence suggesting the mutation, most recently found in Hong Kong of China and Norway, is associated with severe cases of infection, the WHO said.

“We really need to look at this very carefully to see whether it is in fact associated with severe cases,” said WHO spokesman Thomas Abraham.

Mr. Abraham said investigations would be done through the WHO’s collaborating network of laboratories and “through understanding more about clinical features associated with the infection of this particular form of the virus.” According to Mr. Abraham, there was currently no evidence suggesting the mutated form of the A(H1N1) flu virus was spreading. The mutations appeared to occur sporadically and spontaneously.

Norwegian health authorities last week informed the WHO of a mutation of the A(H1N1) flu virus detected in two patients who died and one with severe illness.

Hong Kong’s Department of Health announced on Monday that it also had found the same mutation in an A(H1N1) flu virus sample.

Keywords: WHOA(H1N1)researchflu virus

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