“Particularly for women and girls in countries where limited social protection measures are in place, economic hardships caused by the crisis will have spill-over effects as families consider the financial and opportunity costs of educating their daughters. While many girls will continue with their education once the school gates reopen, others will never return to school,” Stefania Giannini, UNESCO’s Assistant Director-General for Education said.

“Hydroxychloroquine use with or without co-administration of azithromycin did not improve mortality or reduce the need for mechanical ventilation in hospitalised patients,” the scientists wrote in the study.

On the contrary, they said, hydroxychloroquine use alone was associated with an increased risk of death compared to standard care alone.

Business leaders in the hospitality and restaurant sectors were the most vulnerable with 41% of executives saying their firms were at risk of not surviving, while 30 per cent in aviation and 19 per cent in wholesale and retail sales feared they may go under, the survey found.

Almost two-thirds of business leaders forecast a negative impact on earnings to continue for more than a year, while a quarter expect their workforce to be down by more than 20 per cent a year from now.

“All available evidence suggests the virus has an animal origin and is not manipulated or constructed in a lab or somewhere else,” WHO spokeswoman Fadela Chaib told a Geneva news briefing. “It is probable, likely, that the virus is of animal origin.”

It was not clear, Chaib added, how the virus had jumped the species barrier to humans but there had “certainly” been an intermediate animal host. “It most likely has its ecological reservoir in bats but how the virus came from bats to humans is still to be seen and discovered.”