Eight Venezuela soccer players in Brazil for the Copa America have tested positive for COVID-19, health officials said on Saturday, a day before they meet the hosts in the tournament's opening game.

The "members of the delegation include players and members of the backroom staff," said a statement from the Health Secretariat in Brasilia, where Sunday's game will take place.

The South American Football Confederation (CONMEBOL) made the diagnosis on Friday and informed local health authorities.

"All are asymptomatic, isolated in individual rooms, and are being monitored by the CONMEBOL team and local health officials," the statement said.

CONMEBOL said that in total 13 members of the Venezuela delegation tested positive. Brazilian Health Minister Marcelo Quiroga put the number at 12.

Venezuela said it was 11 and announced it was calling up an additional group of players to join the squad for the month-long tournament.

Venezuela are due to take on reigning champions Brazil on Sunday at the Mane Garrincha stadium.

The Copa America, the oldest tournament in international football and featuring 10 South American nations, was moved to Brazil less than two weeks ago by CONMEBOL after co-hosts Argentina and Colombia were unable to fulfil their commitments due to civil unrest and COVID-19 concerns.

Brazil agreed to host the tournament - scheduled to conclude on July 10 - in spite of its own coronavirus issues.

Some 484,235 people have died in Brazil, more than any country in the world bar the United States, with 2,216 reported dead on Friday.