A boy from the Yanomami tribe in Brazil’s northern Amazonian territory has died after being admitted to a hospital last week with symptoms related to the coronavirus.

Indigenous health officials with Brazil’s Ministry of Health have confirmed that Alvanei Xirixan, 15, died on Thursday night in intensive care at Roraima General Hospital in Boa Vista. On Wednesday, Brazil’s health minister, Luiz Henrique Mandetta, said in a press conference that the teenager had been admitted on April 3 for a suspected COVID-19 infection. He was tested for the virus twice, with a positive result revealed only during the second exam.

“Today we had a confirmed case among the Yanomami, which is very worrying,” said Mandetta. “This is a government concern for indigenous health.”

Despite minimal contact with conventional society, anthropologists and other experts warn that the coronavirus has the potential to wipe out the Yanomami, the Amazon’s largest native tribe with over 26,000 of its 38,000 members living on a massive reserve roughly the size of Indiana, near the Brazilian-Venezuelan border. Indigenous communities across the Americas are similarly threatened — primarily by outsiders who illegally enter their villages, says the Socio-Environmental Institute (ISA).

“Today, without a doubt, the main vector for the spread of COVID-19 inside the Yanomami Indigenous Territory is the more than 20,000 illegal miners that go in and out of the territory without any control,” ISA said in a statement, as reported by CNN.

Brazilian natives are far from the only ones under siege by the virus. The Kokama tribe, on the Amazon river near the Colombian-Peruvian border, have reported at least four cases — caused by a doctor who came to help, but later tested positive for the coronavirus, Reuters reported. The Yukpa people of Colombia have at least two ill with COVID-19 in their numbers, too.

In terms of North America’s native groups, Canada’s Six Nations of the Grand River has suffered at least 8 positive cases and one death, And, here in the US, the West coast’s Navajo Nation, a 27,413-square-mile swath of land between Arizona, New Mexico and Utah, has called for testing of over 2,000 of its members. As of Saturday April 4, at least 321 of those came back positive, and three people have died, the Albuquerque Journal reported. According to the 2010 census, some 156,823 people were living in the Navajo Nation territory — though most of the Navajo contingency have moved away from the reserve to more urban settings.

Compare that to New Mexico, with a population of over 2 million. Out of 16,828 test administered across the state, 543 revealed a positive COVID-19 diagnosis, and just 11 of those people have died.

Dr. Sofia Mendonça, a researcher at the Federal University of São Paulo, told BBC News earlier this week, “There is an incredible risk of the virus spreading across the native communities and wiping them out.

“Everyone gets sick, and you lose all the old people, their wisdom and social organization,” she added. “It’s chaos.”