The current H1N1 swine flu pandemic is relatively less severe than some other influenza outbreaks, the World Health Organisation said on Wednesday.

"This pandemic appears to be on the less severe side of the spectrum of pandemics that we have seen in the 20th century," the United Nations health agency's top flu expert, Keiji Fukuda, said during a briefing.

He was speaking the day after the WHO's emergency committee decided it was premature to declare that the current pandemic, declared in June, had peaked. The committee will reconvene in a few weeks.