The announcement comes as researchers warn that new drug-resistant bacteria could pose a 'major global health problem'.

Following a meeting of its emergency committee, the WHO announced that the world was now in a ‘post-pandemic period’, but that some groups remain at risk of severe illness from the virus.

‘The world is no longer in phase 6 of influenza pandemic alert,’ WHO Director-General Dr Margaret Chan said. ‘We are now moving into the post-pandemic period. The new H1N1 virus has largely run its course.’

The WHO has issued a set of recommendations on monitoring respiratory disease activity, vaccination and clinical management.

The WHO said that a number of groups remain at increased risk of severe illness from the pandemic H1N1 virus. These include young children, pregnant women, and people with underlying respiratory or other chronic conditions, including asthma and diabetes.

Patients who have severe or deteriorating influenza should be treated as soon as possible with oseltamivir, the WHO said.Those who are at higher risk of severe or complicated influenza should be treated with oseltamivir or zanamivir as soon as possible. 

Researchers writing in The Lancet Infectious Diseases have warned that a new gene that enables bacteria to be highly resistant to almost all antibiotics has been found in 37 patients in the UK. Several of the UK patients had undergone surgery while visiting India or Pakistan.

The researchers warn that a 'major global health problem' could be posed by these gram-negative Enterobacteriaceae with resistance to carbapenem conferred by New Delhi metallo-β-lactamase 1.

‘The potential for wider international spread of producers and for NDM-1-encoding plasmids to become endemic worldwide, are clear and frightening,' they said.

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