WHO declares global swine flu pandemic

After holding an emergency meeting, the World Health Organisation (WHO) officially declared a worldwide swine flu pandemic on Thursday. The agency increased its pandemic alert level to the sixth level, its highest.

"On the basis of available evidence, and these expert assessments of the evidence, the scientific criteria for an influenza pandemic have been met. I have therefore decided to raise the level of influenza pandemic alert from phase 5 to phase 6," said the the WHO's director Margaret Chan in a press conference earlier today.

According to Reuters, Chan earlier sent out a letter to WHO staff saying, "With today's announcement, WHO moves from an emergency to a longer-term response. Based on past experience, this pandemic will be with us for some months, if not years, to come."

Chan, however, stressed the move does not indicate that the influenza has become more deadly or severe. "Moving to pandemic phase six does not imply we will see increases in deaths or serious cases," she said. The WHO says that many of the severe cases of the virus are reported in people with prior chronic illnesses. Of those infected, the WHO says the majority are aged from 30 to 50 years old.

Currently, the WHO's official tally says there were almost thirty thousand confirmed cases of the H1N1 virus so far, with about 141 fatalities from the disease.