Fears Covid-19 could 'wipe out' native communities are growing after a boy from an Amazon tribe fell critically ill.
The 15-year-old is a member of the Yanomami community, along the Brazilian-Venezuelan border.
He is now in intensive care after being admitted to the General Hospital of Roraima suffering with fever and severe chest pain.
They are believed to be the largest indigenous tribe in Brazil. Yanomami people occupy over 200 villages across 2.3million acres.
There are currently 18,177 confirmed cases of coronavirus in Brazil and nearly 1,000 deaths.
São Paulo researcher Dr Sofia Mendonça told BBC News : "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. It's chaos."
To tackle the Covid-19 outbreak, members of many communities are breaking off into smaller groups, according to reports in south America.
President of the Federation of Indigenous Organizations of Rio Negro Marivelton Baré said some local communities are "in a panic".
He said: "We'll need to take the food to the villages so that they don't expose themselves during this critical moment."
There are now nearly 1.5million coronavirus cases reported worldwide.