Global report: WHO says 'evidence emerging' of airborne coronavirus spread

The World Health Organization has acknowledged new evidence that the coronavirus spreads more widely in the air than it had previously suggested, as the Trump administration gave official notification of its withdrawal from the group.

A day after a group of scientists said the global body was underplaying the risk of airborne transmission between people, a senior WHO official said there was “evidence emerging” of airborne transmission of the coronavirus, but that it was not definitive.

Speaking at a media briefing in Geneva on Tuesday, Benedetta Allegranzi, the WHO’s technical lead for infection prevention and control, said: “…The possibility of airborne transmission in public settings – especially in very specific conditions, crowded, closed, poorly ventilated settings that have been described, cannot be ruled out.

“However, the evidence needs to be gathered and interpreted, and we continue to support this.”

The WHO has previously said the virus that causes the Covid-19 respiratory disease spreads primarily through small droplets expelled from the nose and mouth of an infected person that quickly sink to the ground.

But in an open letter to the Geneva-based agency, published on Monday in the Clinical Infectious Diseases journal, 239 scientists in 32 countries outlined evidence that they say shows floating virus particles can infect people who breathe them in. Because those smaller exhaled particles can linger in the air, the scientists in the group had been urging WHO to update its guidance.

“We wanted them to acknowledge the evidence,” said Jose Jimenez, a chemist at the University of Colorado who signed the paper.

“This is definitely not an attack on the WHO. It’s a scientific debate, but we felt we needed to go public because they were refusing to hear the evidence after many conversations with them,” he told Reuters.

Jimenez said historically, there has been a fierce opposition in the medical profession to the notion of aerosol transmission, and the bar for proof has been set very high. A key concern has been a fear of panic.

“If people hear airborne, healthcare workers will refuse to go to the hospital,” he said. Or people will buy up all the highly protective N95 respirator masks, “and there will be none left for developing countries.”

The WHO briefing came as the United States government gave formal notification of its intention to leave the organisation next year. Washington has accused the WHO of being too close to the government in Beijing and of not giving the world enough warning about the dangers of the coronavirus after it emerged in China in January.

The move has almost no support from other countries and Joe Biden, the presumptive Democratic presidential candidate, said he would not follow through with the withdrawal if he is elected in November and said the US should instead push for reform of the WHO.

Jeff Merkley, the top Democrat on the Senate foreign relations subcommittee that oversees multilateral institutions, called the move “a huge win for China and a huge blow to the American people”.

The US edged closer to recording 3 million cases of Covid-19 on another day of sharp rises across southern and south-western states. Both California and Texas reported more than 10,000 new cases on Tuesday.

Some reports said the US had already passed the latest milestone in what is the largest outbreak in the world. But figures from Johns Hopkins University said there were just under 2,995,000 by Tuesday evening out of global total of 11.79m infections.

More than 130,000 people have died in the US and Dr Anthony Fauci, the country’s leading infectious diseases expert, said it was still “knee-deep” in the pandemic.

The president of Brazil, Jair Bolsonaro, has tested psoitive for Covid-19. “There’s no reason for fear. That’s life,” said Bolsonaro, a rightwing populist who has consistently rubbished the risks from the disease even as it the country has racked up 1.6 million cases and seen 66,000 of its people die.

In Australia there was chaos at the border between Victoria and New South Wales as roads linking the two states were closed for the first time in 100 years in an effort to suppress an outbreak of Covid in the former’s capital, Melbourne.

Motorists endured long waits as they exited Victoria at the border town of Wodonga, with police checking every driver that they had a permit to leave.

There were 127 new cases of Covid-19 in Victoria on Tuesday, the state premier said on Wednesday morning, down from 191 the day before.