A potentially devastating outbreak ofswine flu among the Yanomami Indians in Venezuela's Amazon rain forest appears to be contained for now after a rapid medical response in the remote zone.

Considered the largest isolated Amazon tribe, with a population of about 30,000, the Yanomami had limited contact with the outside world until 50 years ago. Illnesses brought by gold miners have hit them hard in the past.

Symptoms of swine flu -- possibly spread by outsiders at a government-organized event in mid-October -- showed up in more than 1,000 Yanomami, local health officials said. Six deaths are being investigated for possible links to the H1N1 virus.

Neris Villalobos, chief epidemiologist for Amazonas state, said the initial outbreak peaked at the end of October and the number of new cases has declined sharply.

The action taken has been successful, although we cannot yet say that the situation is over, Villalobos told Reuters in Puerto Ayacucho, capital of Amazonas.

She said medical practitioners had yet to visit far-flung villages to check for possible undetected cases. Medics have given the flu drug Tamiflu, made by Swiss-based Roche, to more than 2,000 villagers in the tribal area, which is accessible only by river or aircraft.

Many of the medics are Cuban or Cuban-trained and form part of President Hugo Chavez's nationwide drive to put doctors in remote communities.

If they had not taken the measures in a timely fashion, this would have been a truly enormous epidemic, said Cuban doctor Giovanni Castellano.

CHANGING WAYS

About 30 doctors are now permanently stationed on the Venezuelan side of the Yanomami region, which straddles the Brazilian border and is roughly the size of Greece.

Illegal mining in the region, especially on the Brazilian side, introduced diseases among the tribe in the 1980s that killed about 20 percent of them.

Tribe members typically live in circular communal huts built around a courtyard. The men hunt for food and the women plant different crops in clearings.

The H1N1 virus appears to have begun among the Yanomami during a meeting organized by government officials to mark the October 12 anniversary of the arrival in the Americas of explorer Christopher Columbus, medics said.

U.K.-based Indian rights group Survival International said it was doubtful the outbreak had been contained.

Given the nature of how it is incubated and spread, and its unpredictability, I just don't think one can say that with any certainty, said Survival spokeswoman Fiona Watson.

She said the Yanomamis' vulnerability to disease meant the reserve should have been sealed to all but health teams after the virus first spread globally earlier this year.

Unprecedented attention from the socialist Chavez government is bringing rapid change to the tribe.

Literacy projects, agricultural training and government jobs are now part of daily life for many of the Indians.

The state is fomenting cultural changes in these people. It's not new but it's happening faster. The most negative aspect is politicization, said one local expert on Yanomami health who asked not to be named.

Yanomami Francisco Sutti, 52 -- who ferries doctors between villages along the maze of waterways in the reserve -- said many jobs were handed out by politicians.

The doctors have been good to me, but the politicians are always fighting, and people sometimes lose their jobs if they speak to someone from another party, he said.