WHO Declares International Concern Over Swine Flu

A quarantine officer monitors travelers from Mexico City with a thermographic device at an arrival...

A quarantine officer monitors travelers from Mexico City with a thermographic device at an arrival gate at Narita International Airport in Narita, Japan, Saturday, April 25, 2009. The device measures the temperatures of passengers. Some Asian nations enforced checks Saturday on passengers and pork products from Mexico amid fears that its deadly outbreak of swine flu might spread to a continent that has battled hard to contain bird flu. (AP Photo/Kyodo News)

(AP)

The World Health Organization warned countries around the world Saturday to be on alert for any unusual flu outbreaks after a unique new swine flu virus was implicated in possibly dozens of human deaths in North America.

WHO Director-General Margaret Chan said the outbreak in Mexico and the United States constituted a "public health emergency of international concern."

The decision means countries around the world will be asked to step up reporting and surveillance of the disease, which she said had "pandemic potential" because it is an animal virus strain infecting people. But the agency cannot at this stage say "whether or not it will indeed cause a pandemic," she added.

Chan made the decision to declare public health emergency of international concern after consulting with influenza experts from around the world. The emergency committee was called together Saturday for the first time since it was created in 2007.

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In theory, WHO could now recommend travel advisories, trade restrictions or border closures, none of which would be binding. So far it has refrained from doing so.

The agency also held off raising its pandemic alert level, citing the need for more information.

Earlier, Chan told reporters that "it would be prudent for health officials within countries to be alert to outbreaks of influenza-like illness or pneumonia, especially if these occur in months outside the usual peak influenza season."

"Another important signal is excess cases of severe or fatal flu-like illness in groups other than young children and the elderly, who are usually at highest risk during normal seasonal flu," she said.

Several Latin American and Asian countries have already started surveillance or screening at airports and other points of entry.

At least 62 people have died from severe pneumonia caused by a flu-like illness in Mexico, WHO says. Some of those who died are confirmed to have a unique flu type that is a combination of bird, pig and human viruses. The virus is genetically identical to one found in California.