WHO chief says swine flu has pandemic potential

By Stephanie Nebehay

GENEVA (Reuters) - Outbreaks of swine flu in humans in Mexico and the United States have the potential to cause a worldwide pandemic but it is too early to say whether they will, the World Health Organisation said on Saturday.

WHO director-general Margaret Chan, after taking advice from experts who held emergency talks, declared the outbreaks to be a "public health emergency of international concern." This means there is a risk of the new disease spreading to other countries.

In a statement, she urged health authorities worldwide to be on high alert for unusual patterns of disease and any rise in flu-like cases or severe pneumonia, and report them to the WHO.

"This is clearly an animal strain of the H1N1 virus and it has pandemic potential because it is infecting people," Chan said earlier on a teleconference.

"However, we cannot say on the basis of currently available laboratory, epidemiological, and clinical evidence whether or not it will indeed cause a pandemic."

The United Nations health agency has warned for several years that a new virus strain could spark a human influenza pandemic that could sweep around the globe and kill millions.

The new H1N1 flu strain -- a mixture of swine, human and avian flu viruses which has killed up to 68 people among 1,004 suspected cases in Mexico and infected eight in the United States -- is still poorly understood and the situation is evolving quickly, Chan said.

The emergency committee of experts that held three-hour talks with Chan and senior WHO officials on Saturday heard reports from the U.S. and Mexican authorities.