Dr. Margaret Chan of the World Heath Organization (WHO) has officially raised the status of H1N1 Swine Flu to six, the highest level.

Dr. Chan said there are two main concerns now:

a) a second wave of the flu is to be expected, probably within the next 6 to 9 months, and

b) in developing countries who have not yet come into their influenza season, that they may not be able to cope well with H1N1 when it arrives.

The virus which is currently called Swine Flu is still a somewhat mild version, meaning it is more severe than normal flu but not yet killing too many people.

Influenza viruses are notorious for quickly changing their behaviour and because of that the concern is that it could mutate into something much more severe.

The last Pandemic was in 1968 when Hong Kong Flu killed some 50,000 people.

Almost 30,000 have been infected by the H1N1 virus in some 74 countries according to the WHO.

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