The United Nations warned of potentially “dire” long-term effects of the coronavirus outbreak on countries and the global economy and called for greater international cooperation to fight the pandemic.

“COVID-19 is the greatest test that we have faced together since the formation of the United Nations,” said UN Secretary-General Antonio Guterres as he launched a report this week to address responses to the crisis. The UN was founded 75 years ago, after World War Two.

The UN report appealed to countries to follow the World Health Organization’s (WHO) guidelines and for an immediate health response to curb the spread of the virus, including stepping up testing, quarantine and treatment.

“We are still very far from where we need to be to effectively fight the COVID-19 worldwide and to be able to tackle the negative impacts,” Guterres told reporters at a virtual news conference.

Guterres said he was particularly concerned for Africa and urged developed countries to do more for less prepared nations.

“Let us remember that we are only as strong as the weakest health system in our interconnected world,” Guterres said.

The report also called for a multilateral response amounting to at least 10% of global gross domestic product.

Over 878,000 people worldwide have been infected with the novel coronavirus and over 43,000 people have died, according to Reuters data.