Nearly a year after scientists showed that the coronavirus could be inhaled into tiny droplets called aerosols that linger inside stagnant air, more than a dozen experts called on the Biden government to take immediate action to stop the transmission of limit the virus in the high risk. institutions such as meat packaging plants and prisons.
The 13 experts – including several who advised President Biden during the transition – urged the government to devise a combination of masks and environmental measures, such as better ventilation, to numb the risks in different workplaces.
The Centers for Disease Control and Prevention issued new guidelines on Friday for reopening schools, but improved ventilation was quickly passed on as a precaution. The World Health Organization only conceded in July that the virus could linger in overcrowded indoor spaces in the air, after 239 experts publicly requested the organization to do so.
In a letter to the government, scientists set out evidence to support the transmission of the virus into the air. It has become even more urgent for the government to take action now, experts said, due to the slow explosion of the vaccine, the threat of more contagious variants of the virus already spreading in the United States and the high percentage Covid-19 infections. and deaths, despite a recent decline in business.
“It’s time to stop the fact that the virus is mostly transmitted through the air,” said Linsey Marr, an aerosol expert at Virginia Tech.
“If we acknowledge this properly and get the right recommendations and guidance in place, this is our chance to end the pandemic in the next six months,” she added. “If we do not do that, it could very well continue.”
The letter was delivered Monday to Jeffrey D. Zients, coordinator of the Biden administration’s Covid-19 response. Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention; and Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases.
The letter calls on the CDC to recommend the use of high-quality masks, such as N95 respirators, to protect workers at high risk of infection. At present, healthcare workers mostly rely on surgical masks, which are not as effective at spreading aerosol from the virus.
Many experts who are very vulnerable to infection are people of color who have borne the brunt of the epidemic in the United States.
Mr. Biden has instructed the Occupational Safety and Health Administration, which sets the requirements of the workplace, to issue temporary emergency standards for Covid-19 by March 15, including those regarding ventilation and masks.
But OSHA will only impose standards supported by the leadership of the CDC, said David Michaels, an epidemiologist at George Washington University and one of the signatories.
(Dr. Michaels led OSHA during the Obama administration; the agency has not had a permanent leader since his departure.)
“Until the CDC makes some changes, OSHA will have trouble changing the recommendations it offers because there is an understanding that the government needs to be consistent,” said Dr. “And CDC has always been seen as the main agency for infectious diseases.”
Public health institutions, including the WHO, are slow to recognize the importance of aerosols in the spread of the coronavirus. The CDC only acknowledged in October that the virus could sometimes take place in the air, following a mysterious event in which a description of how the virus spread appeared on the agency’s website disappeared and reappeared two weeks later.
But the agency’s recommendations on workplace accommodation do not reflect this change.
Early in the pandemic, the CDC said health workers do not need N95 respirators, and may even wear bandannas to protect themselves. It also did not recommend face masks for the rest of the population.
The agency has since reviewed the recommendations. It has recently been recommended that people wear two masks or better fit their surgical masks to protect them from the virus.
“But they are not talking about why you need a better mask,” said Dr. Donald Milton, an aerosol expert at the University of Maryland, said. “They recognize the importance of inhaling it and the route of dispatch, and yet they do not say it clearly on their various web pages.”
The agency recommends surgical masks for health professionals and says N95 respirators are only needed during medical procedures that produce aerosols, such as certain types of surgery.
But many studies have shown that healthcare workers who have no direct contact with Covid-19 patients also have a high risk of infection and have to carry high-quality breathing machines, says Dr. Céline Gounder, a specialist in infectious diseases at Bellevue Hospital. in New York and an adviser to Mr. Pray during the transition.
“The CDC did not stress enough the risk of aerosol transfer,” said Dr. Gounder said. “Unfortunately, the discussion remains muddy about the offer.”
Many hospitals still expect their staff to reuse N95 masks according to the agency’s recommendation to reuse if stock is low. But since the masks are no longer in short supply, the agency must change its recommendations, said dr. Gounder said.
“We really need to stop using this and re-contaminating N95s,” she added. “There’s a year in there, and that’s really not acceptable.”
Hospitals have at least good ventilation so that health care workers are protected in other ways, the experts said. But in meat packaging plants, prisons, buses or grocery stores, where workers are exposed to the virus for a long time, the CDC does not recommend a high-quality respirator, and also endorses the upgrade of ventilation.
“If you go to other workplaces, this idea that aerosol transfer is important is virtually unknown,” Dr. Michaels said. In food processing plants, for example, a chilled environment and the lack of fresh air are the ideal conditions for the virus to thrive. But the industry has not taken safety measures to limit the risk, he added.
Employers rather like the CDC’s recommendations for surfaces that physically relinquish and clean.
The recent emergence of more infectious variants urgently requires the CDC to address the transmission of the virus into the air, said Dr. Marr of Virginia Tech said. Germany, Austria and France now commission N95 respirators or other high-quality masks in public transport and shops.
Dr Marr was one of the experts who wrote to the WHO last summer to seek recognition of air transport. She did not expect to be in a similar position again so many months later. She said, ‘It feels like Groundhog Day.’