Brazil has overtaken Spain and Italy to become the country with the fourth-largest number of confirmed coronavirus infections in the world.
Officials on Saturday reported 14,919 new cases in the past 24 hours, taking the total to 233,142. Only the US, Russia and the UK have higher numbers.
The death toll in Brazil over 24 hours was 816, bringing the total to 15,633 - the world's fifth-highest figure.
Experts warn that the real figure may be far higher due to a lack of testing.
The mayor of the country's most populous city, São Paulo, warned on Sunday that the city's health system could collapse. Bruno Covas said the public hospitals in the city reached 90% capacity for emergency beds, with demand still growing.
Mr Covas said he was in crisis talks with the state governor over introducing a strict lockdown to try to slow contagion before hospitals ran out of space in an estimated two weeks' time.
Health experts in Brazil have warned that the real number of confirmed infections in the country may be far higher than the official records, due to a lack of testing.
"Brazil is only testing people who end up in the hospital," Domingo Alves from the University of São Paulo Medical School told AFP news agency last week.
"It's hard to know what's really happening based on the available data. We don't have a real policy to manage the outbreak," he said.
Mr Alves is one of the authors of a study that estimated the real number of infections was 15 times higher than the official figure.
Brazil's far-right president Jair Bolsonaro has been strongly criticised both at home and abroad for his handling of the country's escalating coronavirus crisis.
Mr Bolsonaro continues to oppose lockdown measures. He has downplayed the virus as "a little flu" and has said the spread of Covid-19 is inevitable.
In April, Mr Bolsonaro joined protesters demanding that lockdown restrictions be lifted. He says the restrictions are damaging the country's economy, bringing unemployment and hunger.
Last week, Brazilian Health Minister Nelson Teich resigned after less than a month in the job. Mr Teich stepped down after he had publicly criticised a decree by Mr Bolsonaro allowing gyms and beauty parlours to reopen. Mr Teich's predecessor was sacked after disagreeing with Mr Bolsonaro.
In the face of mixed messages, and with little government help at hand, not enough Brazilians are staying at home to slow the spread of the virus, the BBC's Americas editor Candace Piette says.
What's the latest in the wider region?
Brazil, by far the largest country in Latin America, has for several weeks been at the centre of the coronavirus outbreak.
Latin America and the Caribbean have recorded more than 500,000 infections, with Brazil accounting for nearly 50% of the cases.
Mexico has recently seen a spike in new infections, while Ecuador saw its health system collapse in April.
The sharp rise in cases in Latin America has led the World Health Organization (WHO) to say the Americas are currently at the centre of the pandemic.
In March, the WHO had labelled Europe the "epicentre of the pandemic" but the region is now slowly beginning to ease restrictions brought in to slow the spread of the virus.