The advice came as America logged another huge rise in its death toll — almost 1,500 in one day — and as new infections continued unabated, according to AFP.

The World Health Organization said that medical masks should be prioritized for health workers, but it opened the door to greater public use of homemade masks or other mouth coverings as a way to reduce the spread of the coronavirus.

According to Reuters, a senior WHO official told reporters there was some possibility of airborne transmission of the virus that has now infected over one million people and killed 50,000 people worldwide since emerging in China last December.

But the main driver of the pandemic was still believed to be sick people with symptoms who were coughing and sneezing and contaminating surfaces or other people.

“We must preserve medical surgical respirator masks for our frontline workers. But the idea of using respiratory coverings or mouth coverings to prevent coughing or sneezing projecting disease into the environment and towards others … that in itself is not a bad idea,” Dr. Mike Ryan, the WHO’s top emergencies expert, told a news conference.

Since COVID-19 emerged late last year, around 1.1 million people have fallen ill. Almost 60,000 people have died.

Europe accounts for the lion’s share of the dead, with Italy and Spain bearing the brunt.

But the situation is rapidly deteriorating in the United States, and President Donald Trump’s administration on Friday suggested widespread use of simple masks or scarves might help stem the rocketing infection rate.

“It’s going to be really a voluntary thing,” he said. “You don’t have to do it and I’m choosing not to do it, but some people may want to do it and that’s okay.”

Anthony Fauci, head of infectious diseases at the US National Institutes of Health, cited “recent information that the virus can actually be spread even when people just speak as opposed to coughing and sneezing.”

The US recommendation will likely worsen an already severe shortage of masks in the United States and Europe, which both rely heavily on imports from China.

Officials in New York, the worst affected part of the US, began advising people to wear masks some days ago, and there were signs on the streets that the advice was being heeded.

“I am trying to protect me and my family. If everybody protects themselves, it’s better for all of us,” Eddie Marrero, a 58-year-old handyman, told AFP.

Around 277,000 Americans have tested positive for the disease, and the infection curve shows no sign of flattening, despite nine in ten citizens living under some sort of lockdown.

Field hospitals are sprouting in convention centers, sports arenas and parking lots all over the country as states gird for an expected influx of patients.

China, which appears to be over the worst of its outbreak, on Saturday held a national day of mourning for its dead — well over 3,000 people have died in the country where the virus first emerged late last year.

Cars, trains, and ships sounded their horns, and air-raid sirens wailed, as flags were flown at half staff from 10:00 a.m. (0200 GMT).

Beijing has said the observance is a chance to mourn virus “martyrs” — an honorific title bestowed by the government this week on 14 medical workers who died fighting the outbreak — including the man who was punished by officials for raising the initial alarm.

Spaniard Javier Lara survived after being put on oxygen in an overcrowded intensive care unit —  a shock to a 29-year-old who was athletic and doesn’t smoke.

“I was panicking that my daughter would get infected. When I started showing symptoms, I said I wouldn’t hold her or go near her,” he said, describing facing death with an eight-week-old as the “worst moment” in his life.

But there were also signs the peak may have hit on the continent.

Hardest-hit Italy recorded 766 new deaths but its infections rose by just four percent, the lowest yet, according to the civil protection service.

“It’s true that the latest figures, as high as they are, give us a little bit of hope, as the growth in new infections is slower than it was a few days ago,” said Chancellor Angela Merkel of Germany, where strict social distancing measures are credited with curbing the spread.

“But it is definitely much too early to see a clear trend in that, and it is certainly too early to think in any way about relaxing the strict rules we have given ourselves,” she added.

‘Worst yet to come’

There was, however, yet another warning over the fate of the less developed world, especially conflict zones or places with large refugee populations.

“The worst is yet to come,” UN Secretary-General Antonio Guterres said, referring to countries such as Syria, Libya, and Yemen. “The COVID-19 storm is now coming to all these theaters of conflict.”