The WHO says the swine flu has spread across 23 countries, though most of the cases have been reported in Mexico and the United State
Earlier Thursday, the WHO's acting director-general Keiji Fukuda told Asian officials in Bangkok by videolink that the WHO does not know how severe the swine flu outbreak will become. He warned the virus could get more virulent later in the year during the northern hemisphere's flu season.
If it turns into a pandemic, he said one third of the world's population - up to two billion people - could end up infected.
The United States has confirmed nearly 900 cases of swine flu, while Mexico has reported more than 1,000.
The acting director for the Centers for Disease Control (CDC) Richard Besser said officials expect to see far more cases in the U.S., as well as more deaths. Two fatalities have already been confirmed in the U.S. state of Texas, which borders Mexico, while all 42 other deaths from the virus occurred in Mexico.
Mexican businesses and schools began reopening Wednesday and Thursday after officials said the virus was spreading more slowly in the country.
Other countries have also been easing measures to control the disease.
China on Thursday lifted a seven-day quarantine for passengers who arrived in Shanghai on a flight with a Mexican man who was later found to be infected with the virus.
Also Thursday, Russia announced it was lifting a ban on meat imports from five U.S. states, but added another - Illinois - to its list.
At a Congressional hearing Thursday, U.S. Agriculture Secretary Tom Vilsack said he is disappointed that Russia and China have imposed restrictions on U.S. imports.
Vilsack stressed that U.S. pork products are safe, saying there is no evidence the swine flu virus can be transmitted through food. He said the agriculture department is working hard to reach out to the Russians, the Chinese and other governments to reopen international markets.
07 May 2009