NEW YORK (AP) " The global swine flu outbreak worsened Tuesday as authorities said hundreds of students at a New York school have fallen ill and federal officials said they expected to see U.S. deaths from the virus.
Cuba suspended flights to and from Mexico, becoming the first country to impose a travel ban to the epicenter of the epidemic. The mayor of the capital cracked down further on public life, closing gyms and swimming pools and ordering restaurants to limit service to takeout.
Confirmed cases were reported for the first time as far away as New Zealand and Israel, joining the United States, Canada, Britain and Spain.
Swine flu is believed to have killed more than 150 people in Mexico, and the Centers for Disease Control and Prevention said the U.S. has 68 confirmed cases in five states, with 45 in New York, one in Ohio, one in Indiana, two in Kansas, six in Texas and 13 in California.
"I fully expect we will see deaths from this infection," said Richard Besser, acting director of the CDC.
That was echoed by Homeland Security Secretary Janet Napolitano.
"It is very likely that we will see more serious presentations of illness and some deaths as we go through this flu cycle," she said.
President Barack Obama asked Congress for $1.5 billion in emergency funds to fight the illness.
In New York, there were growing signs that the virus was moving beyond St. Francis Preparatory school, where sick students started lining up last week at the nurse's office. The outbreak came just days after a group of students returned from spring break in Cancun.
At the 2,700-student school, the largest Roman Catholic high school in the nation, "many hundreds of students were ill with symptoms that are most likely swine flu," said Health Commissioner Thomas Frieden. The cases haven't been confirmed.
Twelve teachers reported flu-like symptoms as well, said the principal, Brother Leonard Conway.
A nearby public school for special education students was shut down after more than 80 students called in sick. Frieden said that some of the students have siblings at St. Francis.
"It is here and it is spreading," Frieden said.
Some of the New York students who tested positive for swine flu after a trip to Mexico passed it on to others who had not traveled " a significant fact because it suggests the strain suspected in dozens of deaths in Mexico can also spread through communities in other countries, said Keiji Fukuda, assistant director-general of the World Health Organization.
"There is definitely the possibility that this virus can establish that kind of community wide outbreak capacity in multiple countries, and it's something we're looking for very closely," Fukuda said. So-called "community" transmissions are a key test for gauging whether the spread of the virus has reached pandemic proportions.
Fukuda warned, however, against jumping to the conclusion that the virus has become firmly established in the United States.
Still, U.S. officials stressed there was no need for panic and noted that flu outbreaks are quite common every year. The CDC estimates about 36,000 people in the U.S. died of flu-related causes each year, on average, in the 1990s.
The increase in cases was not surprising. For days, CDC officials said they expected to see more confirmed cases " and more severe illnesses. Health officials nationwide stepped up efforts to look for symptoms, especially among people who had traveled to Mexico.
Scientists hope to have a key ingredient for a vaccine ready in early May, but it still will take a few months before any shots are available for the first required safety testing. Using samples of the flu taken from people who fell ill in Mexico and the U.S., scientists are engineering a strain that could trigger the immune system without causing illness.
"We're about a third of the way" to that goal, said Dr. Ruben Donis of the CDC.
In Mexico City, authorities opened the national naval hospital to civilians to deal with the still-mounting wave of suspected swine flu cases, and prospective patients crowded the waiting rooms and reception areas for a chance to get in.
With at least 152 suspected swine flu deaths in Mexico, complaints were heard throughout the capital of 20 million that the supply of surgical masks was running out.
The economic toll also spread. Officials said Mexico City is losing $57 million a day amid a shutdown that includes schools, state-run theaters and other public places. The government said it was closing all of Mexico's famed archaeological sites until further notice.
Cuba announced a 48-hour ban on flights to and from Mexico, except in "exceptional cases." The last flight from Mexico touched down in Havana around 4 p.m., then returned to Mexico City with passengers before the two-day suspension officially began.
The U.S. stepped up checks of people entering the country and warned Americans to avoid nonessential travel to Mexico. Canada, Israel and France issued similar travel advisories.
For all the government intervention, health officials suggested that efforts to contain the flu strain might prove ineffective. Around the world, officials hoped the outbreak would not turn into a full-fledged pandemic, an epidemic that spreads across a wide geographical area.
"Border controls do not work. Travel restrictions do not work," said WHO spokesman Gregory Hartl, recalling the SARS epidemic earlier in the decade that killed 774 people, mostly in Asia, and slowed the global economy.
The pork industry was dealing with a public relations nightmare over the virus, which is a never-before-seen hybrid of human, swine and bird influenza that is widely called swine flu.
Public health officials have said people cannot get sick from eating pork, but some countries, such as China, Russia and Ukraine, have banned imports from Mexico and parts of the U.S.
U.S. officials said they may abandon the term "swine flu" for fear of confusing people into thinking they could catch it from eating pork.
"It's killing our markets," said Francis Gilmore, 72, who runs a 600-hog operation in Perry, Iowa, outside Des Moines, and worries his small business could be ruined by the crisis. "Where they got the name, I just don't know."
Gov. Arnold Schwarzenegger declared a state of emergency to help California agencies coordinate efforts in response to the outbreak. He cautioned, however, that "there is no need for alarm."
In New York, the city called on the CDC for additional resources to investigate the outbreak at St. Francis Prep.
About 1,500 students replied to surveys sent out by the health department about the outbreak, helping the city get a better sense of how the virus is spreading. Some students have complained of sudden nausea; others dealt with high fever, sore throats, coughs and aches.
Rachel Mele and her mother, Linda, were relieved when the 16-year-old's fever broke Tuesday for the first time in five days. It had been hovering around 101.
The family could finally breathe easy " a relief after a terrifying night Thursday in which Mele's parents bundled her into the car and rushed her to the hospital when they realized she was having trouble breathing.
"I could barely even catch my breath. I've never felt a pain like that before," Mele said. "My throat, it was burning, like, it was the worst burning sensation I ever got before. I couldn't even swallow. I couldn't even let up air. I could barely breathe through my mouth."
Associated Press Writers Marcus Franklin and Samantha Gross in New York; Peter Orsi, Julie Watson and E. Eduardo Castillo, in Mexico City; Mike Stobbe in Atlanta; Mary Clare Jalonick, David Espo, Philip Elliott and Matthew Lee in Washington; Alexander G. Higgins in Geneva, Maria Cheng in London and Pan Pylas in London contributed to this report.