JOHANNESBURG -- African nations came out swinging on the third day of the United Nations annual gathering of world leaders Thursday, calling for dramatic fiscal measures to help economies survive the coronavirus pandemic -- which one leader called the "fifth horseman of the apocalypse."

African countries estimate they need US$100 billion in support annually for the next three years, pointing out it's a fraction of the trillions of dollars some richer countries are using to revive their economies.

Debt cancellation is needed to free up more resources to tackle the virus and its effects, including the fight against other deadly diseases like malaria and HIV, heads of state said. Meanwhile, Africa has tilted into its first recession in a quarter-century.

"We need to purely and simply cancel this debt," said Niger's president, Issoufou Mahamadou.

The president of Ivory Coast, one of the world's fastest-growing economies before the pandemic, called for the extension of a debt moratorium and the issue of special drawing rights at the International Monetary Fund.

"I call on all Africa's partners to take bolder measures," Alassane Ouattara said, noting that the fight against COVID-19 and its economic effects has represented 5% of the country's GDP.

In fact, reforms of Bretton Woods institutions like the IMF and World Bank might be needed to "usher in a fairer international order," Gabon's President Ali Bongo Ondimba said.

The pandemic has exposed the poor funding of health systems across Africa. In a separate briefing Thursday, a World Health Organization official said just 51% of health facilities in sub-Saharan Africa have basic water services.

In their speeches to fellow world leaders, delivered virtually by video messages because of the pandemic, some African heads of state pointed out what Ouattara called an "extraordinary resilience" in the face of the virus. But they made it clear massive help is needed, and some acknowledged they must do more, too.

The Ivory Coast leader, for one, pledged that his country will invest $3 billion in its health system from 2021-2025.

Health experts say Africa has fared far better than the dire predictions made early in the pandemic. There have been over 1.4 million confirmed cases on the continent of 1.3 billion people, and the WHO says the rate of new cases in sub-Saharan Africa has steadily declined for the past two months.

Researchers say possible factors include Africa's relative youth, the later arrival of the virus on the continent and swift lockdown measures that have taken a harsh economic toll. The relatively low number of international air links has protected the continent but hurt the delivery of some life-saving goods like childhood vaccines.

"The pandemic has reversed our gains" on many fronts, including the strengthening of democracy, Gambia's President Adama Barrow said.

Spurred by this year's turmoil over racial injustice and inequality, African nations again demanded a permanent seat on the UN's most powerful body, the Security Council -- or even two. The council reflects a world order of 75 years ago that few people in Africa recognize, some said.

"Certainly, Africa's voice on the council will build confidence and reinforce the legitimacy of its decisions," Barrow said.

As some world powers prefer to go their own way, the African countries that make up more than a quarter of the UN membership are leaning hard into multilateralism as global crises pile up almost beyond belief.

Burkina Faso's President Roch Marc Christian Kabore recalled the UN chief's speech early this year warning against the "four horsemen of the apocalypse," including geopolitical tensions and climate change.

"Unfortunately," he said, "less than two months later, a fifth horseman of the apocalypse, very destructive, the coronavirus, has appeared."