(AP) -- Mexico canceled school nationwide Monday and warned the death toll from a swine flu epidemic believed to have killed 149 people would keep rising before it can be contained. Health Secretary Jose Angel Cordova said 20 of the deaths have been confirmed to be from swine flu and the government was awaiting results on the others.
"We are the most critical moment of the epidemic. The number of cases will keep rising so we have to reinforce preventive measures," Cordova said at a news conference that was briefly shaken by an earthquake centered in southern Mexico.
Cordova said 1,995 people have been hospitalized with serious cases of pneumonia since mid-April, of whom 1,070 have been released. The government does not yet know how many were swine flu.
The virus has been confirmed or suspected in at least a half-dozen other countries and has caused the U.S. to declare a health emergency.
Cordova also suggested an earlier timeline for documented swine flu cases inside Mexico. The first death confirmed by the government involved a woman who succumbed from swine flu on April 13 in southern Oaxaca state. But Cordova said tests now show that a 4-year-old boy contracted the disease at least two weeks earlier neighboring Veracruz state, where a community has been protesting pollution from a large pig farm.
The farm is run by Granjas Carroll de Mexico, a joint venture 50 percent owned by Virginia-based Smithfield Foods, Inc. Spokeswoman Keira Ullrich said the company has found no clinical signs or symptoms of the presence of swine influenza in its swine herd or its employees working at its joint ventures anywhere in Mexico.
But local residents are convinced they were sickened by air and water contamination from pig waste.
There was a widespread outbreak of a particularly powerful respiratory disease in the area early April, and some people reported being sick as early as February. Local health workers intervened in early April, sealing off the town of La Gloria and spraying to kill off flies they said were swarming through their homes.
Cordova said the community was suffering from ordinary influenza - not swine flu. But only one sample was preserved - that of the boy. It was only after U.S. and Canadian epidemiologists discovered the true nature of the virus that Mexico submitted the sample for international testing, and discovered what he suffered from.
The boy has since recovered and Cordova said there have been no new cases detected in the town.
But epidemiologists want to take a closer look at pigs in Mexico as a potential source of the outbreak.
Juan Lubroth, an animal health expert at the U.N. Food and Agriculture Organization in Rome, said a team of veterinarians was flying to Mexico. They will examine what surveillance systems are in place to detect swine flu, and review historical data on previous viruses identified in the country. Farmers will be interviewed.
Lubroth said there have been no reports of sick or dying swine in Mexico, but warned that fears surrounding the outbreak could have a devastating effect on the pork industry.
"Although the virus is reported to have a swine origin, it may have been several years ago, and it's only now that it has shown up in humans as a clinical problem that is spreading," he said.
The Mexican government has yet to say where and how the epidemic began or give details on the victims.
Cordova said the health department lacked the staff to visit the homes of all those suspected to have died from the disease. But he assured that the country had enough medicine to treat the ill.
Meanwhile, Mexico suspended all schools nationwide until May 6, extending an order already in place in Mexico City and five of the country's 32 states, and urged people to stay home if they feel sick.
Labor Secretary Javier Lozano Alarcon said employers should isolate anyone showing up for work with fever, cough, sore throat or other symptoms. And the Mexico City government was considering shutting down all public transportation if the death toll keeps rising. Mayor Marcelo Ebrard said surgical masks were being distributed at subway and bus stops across the city.
The disease has hit hardest in the capital, but life was disrupted from Tijuana to Acapulco, a lucrative Pacific resort town where night clubs and bars were ordered closed until further notice. Acapulco Mayor Manuel Anorve Banos said he was worried about tourists from Mexico City spreading the disease.
Some city dwellers headed to the beach, taking advantage of the closed schools. But those who live day-to-day worried about making ends meet if the city completely shuts down.
"We're going to have to stop working," said Raul Alvarez Torres, who relies on the subway to get from his gritty suburb to his shoe shining stand in an upscale Mexico city neighborhood each day. "If people have no transport, getting around is impossible."
Even as Mexican officials urged those with flu symptoms to seek medical help, some complained of being turned away.
In Toluca, a city west of the capital, one family said health authorities refused to treat a relative Sunday who had full-blown flu symptoms and could barely stand. The man, 31-year-old truck driver Elias Camacho, was even ordered out of a government ambulance, his father-in-law told The Associated Press.
Paramedics complained that Camacho - who had a fever, was coughing and had body aches - was contagious, Jorge Martinez Cruz said.
Family members took him by taxi to a public hospital, but a doctor there denied Camacho was sick and told the trio to leave, Martinez said.
"The government told us that if we have these symptoms, we should go to these places, but look how they treat us," Martinez said. Camacho was finally admitted to the hospital - and placed in an area marked "restricted" - after a doctor at a private clinic notified state health authorities, Martinez said.
Jose Isaac Cepeda, who has had fever, diarrhea and joint pains since Friday, said he was turned away from two hospitals - the first because he isn't registered in the public health system, and the second "because they say they're too busy."
Associated Press writers E. Eduardo Castillo, Niko Price and Olga R. Rodriguez in Mexico and AP Medical Writer Margie Mason contributed to this report.
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