The WHO warned about what it said was an erroneous belief that the COVID-19 crisis is over with jabs on the horizon, nearly a year after the start of the pandemic that has killed 1.5 million people worldwide.
The word of caution comes as the United States clocked a record number of COVID-19 cases for a second day in a row, with the country preparing for what US President-elect Joe Biden has called a "dark winter".
Israel was among the countries battling a new spike, announcing a three-week lockdown from Friday when people will not be allowed more than 500 metres from their homes.
Children aged 12 and over should particularly wear a mask when a one-metre distance from others cannot be guaranteed and there is widespread transmission in the area, the WHO and the United Nations Children’s Fund (UNICEF) said.
The World Health Organization's director-general Tedros Adhanom Ghebreyesus said that without vaccinating the planet's highest-risk populations simultaneously, it would be impossible to rebuild the global economy.
The tally showed the continent had 751,151 cases, 15,721 deaths and 407,461 recoveries. Cases crossed the 500,000 mark on 8 July.
The biggest increases reported on Saturday were from the United States, Brazil, India and South Africa, according to a daily report.
Over 500,000 people have died from the virus since its outbreak in China late last year.
“Still some question about aerosol but likely some degree of aerosol,” said Anthony Fauci, the head of the United States’ National Institute of Allergy and Infectious Diseases.
According to the group, studies have shown the viruses are released during exhalation, talking and coughing in microdroplets, small enough to remain in the air.
The World Health Organisation said it would put out a new scientific brief within days, rounding up the knowledge about how the virus can be transmitted and ensuring its guidance stays in line with the evidence.
Britain has increased the amount of dexamethasone it has in stock and on order to 240,000 doses, health minister Matt Hancock said.
There have now been nine confirmed cases and three probable cases of the disease in and around Mbandaka, the WHO said. Six of those people have died, it added.
The WHO said cigarette firms were still trying out all manner of ways to get youngsters lighting up -- and it was no accident that the vast majority of smokers start before they turn 18.
The study found that administering the medicine or, separately, the related anti-malarial chloroquine, actually increased COVID-19 patients' risk of dying.
The WHA is the supreme policy decision-making body of the WHO, governed by its 194-member states and consisting of health ministers.
The UN health agency cited a new study by its regional office in Brazzaville which found that between 83,000 and 190,000 could die and 29 to 44 million be infected during the period.
The WHO said it had started working with TikTok and Snapchat since the pandemic broke out in a bid to reach out to teen and younger social messaging app users.
