WASHINGTON AND LOS ANGELES — Federal officials declared a public health emergency Sunday as eight cases of swine flu were identified in New York and one was announced in Ohio, bringing the U.S. total of confirmed cases to 20.
In a briefing at the White House, the acting head of the Centers for Disease Control and Prevention, Dr. Richard Besser, warned Americans to prepare for a widespread outbreak, yet urged the public to remain calm.
Also Sunday, Homeland Security Secretary Janet Napolitano said the government would release a quarter of its 50-million-unit strategic reserve of antiviral medications, which combat the disease in infected patients, to states where outbreaks had occurred.
Canadian officials, meanwhile, said four cases had been confirmed in Nova Scotia and two in British Columbia, marking the first time that this particular strain had appeared north of the U.S. border. All six Canadian cases were mild, like those in the United States.
Several other countries have reported influenza-like illnesses that they suspect may be swine flu in travelers returning home from Mexico, but as of Sunday evening, none of them had been confirmed.
Nonetheless, many nations moved quickly to limit the disease's spread, in many cases appearing to be near panic. Some, such as Poland and Venezuela, warned against traveling to the United States or Mexico. Others, such as Russia and Brazil, began screening some incoming international air travelers for signs of high fever.
China, Russia and Taiwan said they would quarantine returning passengers with flu symptoms.
In Mexico, Health Secretary Jose Angel Cordova said almost two dozen more deaths had occurred from influenza overnight, bringing the death total to 103. At least two of the new cases were confirmed as swine flu, for a total of 22 confirmed swine flu deaths. It is not clear how many of the others were caused by the virus.
Of the more than 1,600 suspected flu cases in that country, the Mexican government has said most are probably linked to other strains of the flu or respiratory diseases, not the new strain of swine flu.
On NBC's "Meet the Press," White House Press Secretary Robert Gibbs said swine flu was "serious enough to be a great concern to this White House and to this government." He added that President Obama was receiving frequent updates on the situation.
"We are taking the proper precautions to address anything that happens," Gibbs said. "It's not a time to panic."
