The death toll from COVID-19 in Latin America and the Caribbean passed one million people on Friday, according to a Reuters tally, with the pandemic worsening in the part of the world with the highest per capita death rate.

From the dusty highlands of Bolivia to the Brazilian metropolis of Sao Paulo, the pandemic has swamped underfunded healthcare systems after spreading fast across nations where many people survive hand-to-mouth and have been unable to enter lockdown.

In Peru, among the hardest hit nations in the region, COVID-19 patients have died in crowded hospital corridors of the capital Lima. Deep in the Amazon jungles of Brazil, many residents of the city of Manaus have died at home with no oxygen to fill damaged lungs, after supplies ran out there this year.

With cases falling in Europe, Asia and North America, and flat in Africa, South America is the only region where new infections are rising rapidly on a per capita basis, according to Our World in Data. Although India is currently struggling through one of the world's worst outbreaks of the pandemic.

On average in May, 31 percent of the COVID-19 deaths in the world have been in Latin America and the Caribbean - home to just 8.4 percent of the global population.

Doctors and epidemiologists say the coronavirus pandemic took unprepared governments by surprise last year and its impact has been worsened by leaders who downplayed its gravity and failed to secure timely vaccine supplies.

The top eight countries registering the most COVID-19 deaths per capita over the past week were all in Latin America.

Globally, the real number of dead from the pandemic was "at least two to three times higher than officially reported," said Dr. Samira Asma, the World Health Organization's assistant director-general in charge of data.

"Instead of preparing for the pandemic, we minimized the disease, saying the tropical heat would deactivate the virus," said Dr Francisco Moreno Sanchez, head of the COVID-19 program at one of Mexico's main hospitals and a critic of the government's vaccination plan.

"Unfortunately, we are among the most-affected regions, where the handling of the pandemic has been the most mistaken, and now we are suffering the consequences," said the epidemiologist.