Eight times more people could die of Covid-19 in some parts of the developing world than was previously thought, according to research.
New modelling of the infection fatality rate - the percentage of people who die after contracting coronavirus - in countries including Brazil, India and South Africa suggested death tolls could be "dramatically" higher than expected.
The researchers at the Centre for Global Development (CGD) said the figures were so much higher for some countries because they took into account the impact of the relative weaknesses of the health systems in poorer countries, as well as pre-existing health conditions among the populations.
Previous studies, including from Imperial College, London, and the World Health Organisation, have often incorporated the "demographic advantage" of countries in places such as Africa, which tend to have younger populations.
Data from across the world have shown that older people are at much higher risk of dying with Covid-19.
While the CGD team said this was important, there were other important issues at stake.
"The pandemic is moving into new geographies, it's moving into the global south, and that probably means the mortality rates from Covid-19 are going to change," said Justin Sandefur, a senior fellow at the CGD.
"There has been a lot of focus on the good-news side of that, which is valid. But we have spent our time focusing on factors that cut against that.
"The biggest one is health system capacity . . . the infection fatality rate will look very different in countries with weaker health systems, and the numbers are not quite as optimistic."
To make their predictions, the team took estimates from the infection fatality rate of another viral respiratory infection, influenza, in children under five, aiming to strip out variations in age and comorbidities that typically begin later in life.
After doing this in the five African countries with the biggest epidemics so far - Algeria, South Africa, Cameroon, Kenya and Nigeria - their numbers were twice as high as the modelling from Imperial College, and eight times higher than the WHO's.
The figures came as the WHO warned that the pandemic was "accelerating" in Africa; meanwhile, Afghanistan's health minister said it had already touched "each and every house" in the country; and India recorded 10,000 new daily cases.
On Monday, the WHO said it had seen a record number of new coronavirus cases: 136,000 were reported in just 24 hours.
The disease has already infected seven million globally, and killed more than 400,000.
Brazil recently became the third worst-hit country, after the US and the UK, with just under 40,000 deaths.
In Africa, WHO head Matshidiso Moeti said that while it took 98 days for the continent to reach 100,000 cases, it has taken just 18 to hit 200,000.
In India, health services in the worst-hit cities of Mumbai, New Delhi and Chennai are already swamped.
The country now has the fifth highest rate of confirmed cases in the world, 286,576, with 8,102 deaths, including 357 in the last 24 hours.
"We are sitting on a ticking time bomb," said Dr Harjit Singh Bhatti, president of the Progressive Medicos and Scientists Forum.
Lockdowns in many countries, including India and Brazil, have begun to lift despite the rise in infections.
In almost every country, numbers of infections and deaths are likely to be higher than the official tolls, because of a lack of testing and reporting. (© Daily Telegraph, London)
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