WASHINGTON, D.C. -- President Barack Obama said Monday the threat of spreading swine flu infections was a concern but "not a cause for alarm," while customs agents began checking people coming into the United States by land and air. The World Health Organization said there were 40 confirmed cases in the U.S. but no deaths.
Countries across the globe increased their vigilance amid increasing worries about a worldwide pandemic, Obama told a gathering of scientists that his administration's Department of Health and Human Services "has declared a public health emergency as a precautionary tool to ensure that we have the resources we need at our disposal to respond quickly and effectively."
The acting head of the Centers for Disease Control and Prevention, Dr. Richard Besser, said that Americans should be prepared for the problem to become more severe, and that it could involve "possibly deaths."
The quickening pace of developments in the United States in response to some 1,600 swine flu infections in neighboring Mexico - and reports of over 100 deaths - was accompanied by a host of varying responses around the world. The European Union advised against nonessential travel to the U.S. and Mexico, while China, Taiwan and Russia considered quarantines and several Asian countries scrutinized visitors arriving at their airports.
U.S. customs officials began checking people entering U.S. territory. Officers at airports, seaports and border crossings were watching for signs of illness, said Customs and Border Protection spokesman Lloyd Easterling.
If a traveler says something about not feeling well, the person will be questioned about symptoms and, if necessary, referred to a CDC official for additional screening, Easterling said. The customs officials were wearing personal protective gear, such as gloves and masks, he said.
Multiple airlines, including American, United, Continental, US Airways, Mexicana and Air Canada, said they were waiving usual penalties for changing reservations for anyone traveling to, from, or through Mexico, but had not canceled flights.
The CDC's Besser said that while the U.S. hasn't advised against travel to Mexico, it has urged people to take precautions, such as frequent hand-washing while there.
A private school in South Carolina was closed Monday because of fears that young people who recently returned from Mexico might have been infected.
"We are closely monitoring the emerging cases of swine flu in the United States," Obama said. "I'm getting regular updates on the situation from the responsible agencies, and the Department of Health and Human Services as well as the Centers for Disease Control will be offering regular updates to the American people so that they know what steps are being taken and what steps they may need to take."
"But one thing is clear: Our capacity to deal with a public health challenge of this sort rests heavily on the work of our scientific and medical community," the president said. "And this is one more example of why we cannot allow our nation to fall behind."
Besser, the CDC official, described the new U.S. border initiative as "passive screening." He said authorities were "asking people about fever and illness, looking for people who are ill."
The U.S. declared a national health emergency in the midst of uncertainty about whether the mounting sick count meant new infections were increasing or health officials had simply missed something that had been simmering for weeks or months. The declaration allowed Washington to ship roughly 12 million doses of flu-fighting medications from a federal stockpile to states in case they are needed.
Besser traveled the morning news-show circuit Monday, telling interviewers the U.S. government was being "extremely aggressive" and saying he wouldn't personally recommend traveling to parts of Mexico where the new virus had taken hold.
Besser said he was not reassured by the fact that so far in the U.S., no one had died from the disease.
"From what we understand in Mexico, I think people need to be ready for the idea that we could see more severe cases in this country and possibly deaths," he said. "That's something people have to be ready for and we're looking for that. So far, thankfully, we haven't seen that. But we're very concerned and that's why we're taking very aggressive measures."
Meanwhile, officials of Newberry Academy in South Carolina said Monday that seniors from the school were in Mexico earlier this month and some had flu-like symptoms when they returned.
State Department of Health and Environmental Control spokesman Jim Beasley said test results on the students could come back as early as Monday afternoon. The agency has stepped up efforts to investigate all flu cases in South Carolina. There have been no confirmed swine flu cases in the state.
A New York City school where eight cases were confirmed will be closed Monday and Tuesday, and 14 schools in Texas, including a high school where two cases were confirmed, will be closed for at least the next week. Some schools in California and Ohio also were closing after students were found or suspected to have the flu.
In Mexico, the outbreak's center, soldiers handed out 6 million face masks to help stop the spread of the virus that is suspected in up to 103 deaths. Most other countries are reporting only mild cases so far, with most of the sick already recovering.
Spain reported its first confirmed swine flu case on Monday and said another 17 people were suspected of having the disease. The European Union health commissioner advised Europeans to avoid nonessential travel to Mexico and the United States. Also, three New Zealanders recently returned from Mexico are suspected of having it.
"These are the early days," said World Health Organization spokesman Peter Cordingley. "It's quite clear that there is a potential for this virus to become a pandemic and threaten globally." He said it was spreading rapidly in Mexico and the southern United States.
Worldwide, attention focused on travelers.
"It was acquired in Mexico, brought home and spread," Nova Scotia's chief public health officer, Dr. Robert Strang, said of Canada's first confirmed cases.
Associated Press writers Mark Stevenson and Olga R. Rodriguez in Mexico City; Frank Jordans in Geneva; Mike Stobbe in Atlanta; Maria Cheng in London and Eileen Sullivan in Washington contributed to this report.
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