September 2nd, 2011
08:38 AM ET
For "uncontacted" peoples, like the isolated tribe that went missing last month, a first encounter can be disastrous.
What began 500 years ago with the first Europeans arriving in the New World is still going on in some pockets of Brazil's Amazon rainforest.
Tribes live in isolation when suddenly, new people, carrying new illnesses, show up.
"These groups have been isolated for so long that they haven't built up any immunity like most of us around the world," says Fiona Watson, research and field director of Survival International. "They just don't have the immunity.”
An illness like the common flu can be devastating for these communities.
Since 1988 the Brazilian government has been leaving isolated tribes alone, but monitoring and protecting them from a distance, by satellite and plane.
Only when tribes ask for contact, or are put in danger from other outsiders, will authorities consider making contact.
Following a strict protocol makes first contact possible without anyone becoming ill, says Dr. Alexandre Padilha, Brazil's Minister of Health.
Government officials will administer some 15 different vaccine shots.
"We use such vaccines that are not regularly distributed in the public national system in Brazil, like smallpox" says Padilha. "We try to explain to the Indian people the importance of those vaccines."
Brazil's missing tribe may have fled the suspected drug traffickers passing through their land, but they also may have made contact, which Watson says would be "extremely dangerous."
Health officials in Brazil know the dangers first hand. Contacting and integrating the indigenous peoples was government policy before 1988.
"What they realized is that when they were making these first contacts, which was precisely because of this question of disease, it wasn't uncommon," says Watson, "within the first year of contact, for up to fifty percent of the tribe to die."
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