Mexican Health Secretary Jose Angel Cordova announced Monday evening that officials have identified who they believe to be the earliest known case of the swine flu outbreak: A four-year-old boy in the village of La Gloria, Veracruz, near the huge Granjas Carroll hog operation, which is co-owned by Smithfield Foods of Virginia. But Mexican hog industry leaders and the Governor of Veracruz State argued that the virus originated in China — and passed through the United States before reaching Mexico.

“Government officials today said they believe the swine flu began in a small community next to a large pig farm in the southeastern state of Veracruz, where a four-year-old boy who got sick in April tested positive for the virus,” reported ABC News, which called the small village “Ground Zero,” and said the deadly virus “somehow spread to Mexico City.” (Huffington Post reported this possibility on Sunday)

Until now, the first flu death confirmed by Mexican authorities had been a woman in the southern state of Oaxaca, who died on April 13. But Health Secretary Cordova on Monday “suggested an earlier timeline for documented swine flu cases,” the Associated Press is reporting.

“Cordova said tests now show that a 4-year-old boy contracted the disease at least two weeks earlier in neighboring Veracruz state, where a community has been protesting pollution from a large pig farm,” the AP says. “The farm is run by Granjas Carroll de Mexico, a joint venture 50 percent owned by Virginia-based Smithfield Foods, Inc.”

Company officials said there were no “clinical signs or symptoms” of swine influenza in their vast herds anywhere in Mexico, “But local residents are convinced they were sickened by air and water contamination from pig waste,” AP says. “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 people in the town had normal flu, and only one sample was preserved — that belonging to the four-year-old 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 AP is reporting, adding that the child has recovered and there have been no new cases reported in La Gloria, “But epidemiologists want to take a closer look at pigs in Mexico as a potential source of the outbreak.”

A UN team of animal health experts is flying in from Rome to, “examine what surveillance systems are in place to detect swine flu, and review historical data on previous viruses identified in the country,” AP says, adding that farmers will be interviewed.

Meanwhile, The Wall St. Journal reported Monday night that the Mexican government is testing Smithfield hogs in Mexico, though the huge company insists that its animals are not involved.

“We are very comfortable that our pork is safe,” Smithfield president and chief executive Larry Pope told the newspaper. “This is not a swine issue. This is a human-to-human issue.” He said Mexican agents had already paid site visits to some Smithfield facilities to test hogs and to “confirm that there is ‘no incidence of this virus on our farms.'” Pope said that recent internet postings speculating on the origin of the new virus were “rumors,” and repeated that, “We don’t have any reason to believe that this has anything to do with Smithfield at all.”

“We know of no pigs that are sick, no people on those farms that are sick and no people in our plants” who are sick, he said.

Meanwhile, the Governor of the State of Veracruz, Fidel Herrera, told reporters on Monday that the new virus originated in Asia, and “therefore it is not related to agricultural activity in the area.” He said the virus began in China, and from there passed through the United States directly to Mexico City.

And according to El Universal newspaper, officials at Granjas Carroll México are now claiming that “the virus is of Eurasian origin — and the first cases were found in the United States, making Mexico the receptor nation, more than the generator, of this influenza.” No evidence was published to back up that claim.

Also reported in the Mexican press today, Smithfield and Granjas Carroll have agreed to adopt government recommendations to “begin reinforcing its biosecurity measures to prevent workers and animals from being infected, the newspaper Reforma said.

Reforma also reported that Villagers in La Gloria are being threatened, harassed and even jailed for speaking out against the hog giant.