An expert has warned the number could rise to 800,000 before the country sees the effects of its vaccination programme.
The number of coronavirus deaths in Brazil has now surpassed 500,000 – with thousands taking to the streets to demand the president’s resignation.
Jair Bolsonaro has been accused of failing to acquire vaccines fast enough, prioritising unproven treatments for COVID-19, and questioning whether mask wearing is necessary.
A further 2,301 deaths have been confirmed in the past 24 hours, and experts fear the outbreak – already the world’s second deadliest – may worsen because of government failures.
In downtown Rio de Janeiro, protesters waved signs adorned with slogans such as “500,000 deaths, it’s his fault”.
Another read: “Get out Bolsonaro. Government of hunger and unemployment.”
According to local media, protests have been held in at least 44 cities.
The latest data suggests that just 11% of Brazilians are fully vaccinated against coronavirus, with 29% of the population having received the first dose of a vaccine.
Pfizer said it had offered its vaccines to Brazilian officials between August and November last year, but it is claimed that the government passed up opportunities to buy them.
One demonstrator said: “We are protesting against the genocidal Bolsonaro government that did not buy vaccines and has done nothing to take care of its people in the last year.”
A 20-year-old student who joined the protest in Rio added: “Brazil is experiencing a great setback. The country was an exemplary country for vaccination in the world. We have widely recognized institutions, but today we are in a sad situation.”
Epidemiologists warn that, with winter arriving in the southern hemisphere and new variants of the coronavirus circulating, deaths will continue to mount even if immunisations gain steam.
Gonzalo Vecina, former head of Brazilian health regulator Anvisa, said: “I think we are going to reach 700,000 or 800,000 deaths before we get to see the effects of vaccination.
“We are experiencing the arrival of these new variants and the Indian variant will send us for a loop.”
Raphael Guimaraes, a researcher at a biomedical centre, fears fatalities could return to the average of 3,000 deaths per day seen in March and April.
He said: “We are still in an extremely critical situation, with very high transmission rates and hospital bed occupancy that is still critical in many places.”
Brazil has been registering close to 100,000 new infections a day, edging past India for the most in the world.
Last month, a poll suggested that Mr Bolsonaro’s popularity has sunk to new lows – with just 24% of Brazilians saying his administration is “good” or “great.
The same survey indicated that his left-wing rival, former president Luiz Inacio Lula da Silva, would win in a run-off vote if the 2022 elections were held today.