"The health crisis is...having a severe impact on economic activity," said the IMF in a world economic outlook released on Tuesday.
It projected the global economy would contract by 3% this year – worse than during the 2008-2009 financial crisis.
"Among emerging market and developing economies, all countries face a health crisis...which will have a severe impact on economic activity in commodity exporters," said the report.
The bleak figures were released following a grim prediction by the World Bank, which warned last week that sub-Saharan Africa could slip into its first recession in 25 years because of the coronavirus.
To date, the world's poorest continent has recorded nearly 15,500 cases of the respiratory disease and almost 850 fatalities, according to an Agence France-Presse tally which includes North Africa.
Many African governments used precious time to close borders and impose stay-at-home laws to stem the disease when just a handful of cases had been confirmed.
"Even in countries not experiencing widespread detected outbreaks...the significant downward revision to the 2020 growth projection reflects large anticipated domestic disruptions to economic activity from COVID-19," the IMF said.
Africa's larger economies will be disproportionately affected.
The IMF said fiscal measures provided the keys for easing the slump and helping businesses recover once shutdowns are lifted.
It called on "external support" for countries "facing financing constraints to combat the pandemic."
South Africa's central bank also predicted on Tuesday that the economy would shrink by 6.1% in 2020 as it cut its main interest rate by a full percentage point.
"Fiscal stimulus can preempt a steeper decline in confidence, lift aggregate demand, and avert an even deeper downturn," said the IMF.
"But it would most likely be more effective once the outbreak fades and people are able to move more freely." – Rappler.com