Brazil's brutal surge in COVID-19 deaths will soon surpass the worst of a record January wave in the United States, scientists forecast, with fatalities climbing above 4,000 in a day for the first time on Tuesday as the outbreak overwhelms hospitals.

Brazil's overall death toll trails only the U.S. outbreak, with nearly 337,000 killed, according to Health Ministry data, compared with more than 555,000 dead in the United States.

But with Brazil's health care system at the breaking point, the country could exceed total U.S. deaths, despite having a population two-thirds that of the United States, two experts said.