According to WHO, swine flu pandemic is over.

(Associated Press) The World Health Organisation (WHO) HAS declared the swine flu pandemic officially over, months after many national authorities started cancelling vaccine orders and shutting down hot lines as the disease ebbed from the headlines.

WHO Director-General Margaret Chan said the organisation's emergency committee of top flu experts advised her that the pandemic had "largely run its course" and the world is no longer in phase six, the highest influenza alert level.

"I fully agree with the committee's advice," Chan told reporters in a telephone briefing from her native Hong Kong.

The virus has now entered the "post-pandemic" phase, meaning disease activity around the world has returned to levels usually seen for seasonal influenza, she said.

But Chan cautioned against complacency, saying that even though hospitalisations and deaths have dropped sharply, countries should still keep a watchful eye for unusual patterns of infection and mutations that might render existing vaccines and antiviral drugs ineffective.

"It is likely that the virus will continue to cause serious disease in younger age groups," she said, urging high-risk groups such as pregnant women to continue seeking vaccination.