Until recently, most public health guidelines have focused on social distancing measures, regular hand-washing and precautions to avoid droplets. But the signatories to the paper say the potential of the virus to spread via airborne transmission has not been fully appreciated even by public health institutions such as the WHO.
The fact that scientists resorted to a paper to pressure the WHO is unusual, analysts said, and is likely to renew questions about the WHO’s messaging.
“WHO’s credibility is being undermined through a steady drip-drip of confusing messages, including asymptomatic spread, the use of masks, and now airborne transmission,” said Lawrence Gostin, a professor of global health law at Georgetown University who provides technical assistance to the organization.
He praised the WHO for hosting regular briefings and acknowledged that the organization is in a tough spot because it “has to make recommendations for the entire world and it feels it needs irrefutable scientific proof before coming to a conclusion.”
But he warned that “the public, and even scientists, will lose full confidence in WHO without clearer technical guidance.”
A spokesperson for the organization said it is aware of media reports about the issue and will have technical experts review the matter. The agency has repeatedly defended its handling of the pandemic.
The WHO, which was founded in 1948, is the U.N. agency tasked with promoting global health. It plays a critical role in expanding access to health care, setting up vaccination programs and fighting diseases such as polio.
But its portfolio has grown faster than its budget. And in times of crisis, it has often struggled to lead.
Since the early days of the coronavirus crisis, the WHO and its director-general, Tedros Adhanom Ghebreyesus, have been dogged by questions about whether the agency’s effusive praise for China created a false sense of security and potentially spurred the spread of covid-19, the disease caused by the virus.
That criticism has been compounded at various points by questions about its positions on technical issues, including transmission, mask use — and, now, airborne transmission.
The signatories to the paper contend that the virus can still spread through aerosols, or tiny respiratory droplets, that infected people cough or otherwise release into the air. In crowded or poorly ventilated indoor settings, this could be especially dangerous, and would account for a number of “superspreading” incidents.
“There is no reason for fear. It is not like the virus has changed. We think it has been transmitted this way all along,” said Jose Jimenez, a chemist at the University of Colorado who signed the paper. “Knowing about it helps target the measures to control the pandemic more accurately.”
Co-author Donald Milton, a professor of environmental health at the University of Maryland, said the WHO’s apparent reluctance to emphasize this aspect of the virus’s ability to…