With a new coronavirus variant from the Amazon spurring more infections, according to studies, 1910 people died from the virus in the previous 24 hours, according to Health Ministry data released on Wednesday.

In a year, Brazil's death toll has nearly topped 260,000, the world's second-worst after the United States.

A sputtering vaccination campaign has also put pressure on Health Minister Eduardo Pazuello, who said on Wednesday he was close to an agreement with Pfizer, effectively overcoming a dispute over liability clauses.

The government said it intended buying 100 million doses from Pfizer and 38 million from Janssen, the pharmaceutical subsidiary of Johnson & Johnson.

"We've reached a grave moment of the pandemic. The coronavirus variants are hitting us aggressively," Pazuello said, adding he expected Brazil to receive the Pfizer and Janssen vaccines by May.

The partial lockdown in Sao Paulo, Brazil's most-populous state, underscored mounting concerns about a surging new wave of infections.

The country is facing its deadliest stretch since the pandemic began due to a homegrown variant dubbed P1, scarce restrictions to slow the virus and the patchy vaccine rollout.

Brazil is setting single-day death records as outbreaks ebb in North America and parts of Western Europe.

That risks internationally isolating Latin America's biggest country as other nations seek to shore up their gains against the virus.

The Sao Paulo announcement, made by state Governor Joao Doria, irked far-right President Jair Bolsonaro, who opposes lockdowns and has sought to diminish the gravity of the virus.

But more states and cities are likely to follow Sao Paulo's lead with health systems at breaking point.

Bolsonaro attacked the lockdowns again on Wednesday.

"You cannot panic, like resorting once again to this stay-at-home policy. People are going to die of hunger and depression," he told a group of supporters.

Starting on Saturday, Sao Paulo's bars and restaurants will operate only via delivery, while malls and non-essential businesses will be shut, Doria said.

The measures are due to last two weeks, he said, adding that the state was receiving a new patient in intensive care units every two minutes.

To make matters worse, questions remain about Brazil's stretched vaccine portfolio - comprising an AstraZeneca shot, and another vaccine developed by China's Sinovac Biotech - against the P1 variant.

Australian Associated Press