“How did it come out? Do another one!” says Edgar Hernández, 5, as he poses for photos in the dusty track outside his home in the tiny Mexican town of La Gloria.

Edgar, the world’s most famous victim of swine flu, has found himself at the centre of an outbreak that is threatening to become a global pandemic. He is thought to be the first person to have been confirmed with the virus, and the world’s attention is now fixed on the rural town in Veracruz state, where locals claim that a US-owned pig farm is the source of the disease.

La Gloria’s apparent isolation between soaring mountains — craggy-faced men on horses and carts stare at the television cameras — belies its close ties to the outside world. With the little farm work available in steep decline, many commute on buses to Mexico City. This, say locals, could be the link that the world is searching for.

La Gloria is at the centre of a bitter row concerning an alleged source of the infection — a large pig farm six miles away owned by Carroll, a subsidiary of the US food giant Smithfield. Residents say that an uncovered lake of pig excrement — seen by The Times — seeps into the water and the earth and sends noxious fumes into the air; there are several stories of piles of dead pigs generating swarms of flies.

Though only Edgar’s case has been confirmed as swine flu, locals claim that officials are covering up hundreds of other unconfirmed cases in the area because of the financial power wielded by Smithfield. They point to the deaths of two babies in January and February — the cause of death was never determined. “When they first proposed the farm we all said no,” Edgar’s mother, Maria Hernández, told The Times in the front room of the family home. “It contaminates the air and the earth and there are such bad smells. And there are so many flies. Maybe they brought the illness. Or perhaps we breathed it from the fumes.”

Across the street, neighbours describe years of conflict over the plant. “It has been making us ill for a long time. Sometimes the flies cover the whole roof of your house,” Ofelia Olmos said. “In March maybe 60 per cent of the community was sick. I don’t know what the tests said but the symptoms were the same as the little boy.”

The claims have been dismissed by government officials. Dr Orlando Oscanga Muñoz, the chief medical officer for the municipality of Perote, says that it is “scientifically impossible” that the farm is the source of the outbreak. “It is not transmitted that way, human beings cannot catch it from pigs,” he said.

Perote’s mayor, Guillermo Franco Vázquez, acknowledged that the local incidence of illness this year was “extraordinary”, but he dismissed any link to the plant or cover-up. “We would not put investment ahead of health,” he said.

Mr Vázquez denied that Edgar’s case was the first in Mexico, pointing to the death of a 39-year-old woman in Oaxaca on April 13. Nevertheless no chances are being taken — a civil contingency team has been present in Perote since the beginning of April and at the time of The Times’s visit was spraying streets and urging residents to wash their hands and to wear surgical masks.

The head of the Carroll plant, Victor Manuel Ochoa, said the La Gloria case was “just an unfortunate coincidence”. “Not one of our pigs is sick, not one of our employees is sick,” he said. In Perote one former worker at Carroll who did not wish to be named told The Times that he thought the claims were just gossip. “The conditions are very good there,” he said.

Another local claimed that town leaders in La Gloria had been trying to get Carroll to buy land at ten times the market price. “I think this is basically blackmail,” he said.

Some in La Gloria were similarly sceptical. One disgruntled group, milling on a street corner, lamented the negative attention on their town. One man, who also wanted his identity to remain anonymous, said: “I work in Jalapa, an hour away. If you say there you are from La Gloria they cross the street to avoid you, because they think you are contaminated.

“Worse than the problem of the illness is the economic situation — all our work has been suspended. How are we going to live now?”

Others said that the attention had brought benefits to a town in which government officials were handing out tourist brochures to journalists along with health advice. “We were hardly recognised before,” Mrs Olmos said. “We didn’t have access to medicine or healthcare — now it’s all here.”

As she spoke, workers were mending the road outside Edgar’s house. Asked when the work had started, Alejandra Aguilar, 15, replied: “Today.”

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