Brazil's death toll from the pandemic has surpassed 100,000, making it the world's worst outbreak after the United States.
Activists have marked it with an event on Rio's famous Copacabana beach.
They set out 100 black crosses and released 1,000 red balloons, one for every 100 people who died.
Since May, Brazil has reported an average of 1,000 deaths a day from the pandemic.
But President Jair Bolsonaro has consistently downplayed the crisis, despite being infected by COVID-19 himself.
Al Jazeera's Monica Yanakiev reports from Rio de Janeiro, Brazil.
As of Sunday, Brazil has passed 100,000 COVID-19 deaths. More than 98% percent of Brazilian municipalities have reported coronavirus cases. How Brazilian residents and public health experts react to the country's growing COVID-19 deaths. Peruvian President Martin Vizcarra is reinstating COVID-19 lockdowns after a rise in cases. In July, Peru tried to boost the economy with a phased reopening. Just days after its coronavirus lockdown was extended, the number of cases in Argentina is now past 200,000.
People are being urged to stay at home and all social gatherings have been banned till August 16.
The metropolitan area around Buenos Aires is the worst hit, with 90% of confirmed cases.
Last week President Alberto Fernández cautioned against Argentinians becoming too relaxed. In dueling prime time events - Biden's calm, socially-distanced town hall in Pennsylvania and Trump's unhinged, packed Wisconsin rally - the differences between the 2020 candidates has rarely ever been so clear. Ashley Parker of The Washington Post reacts. Aired on 09/17/2020.