Scientists say WHO ignores the risk of coronaviruses floating in the air as aerosols

About an hour ago

Seattle — Six months after the pandemic killing more than half a million people, more than 200 scientists around the world have disputed the official views on the spread of the coronavirus.

The World Health Organization and the US Centers for Disease Control and Prevention claim that only two types of infections need to be concerned. Inhale respiratory spray from someone in the immediate vicinity of the infected person, or less commonly, touch a contaminated surface and then touch. Nose and mouth.

However, other experts argue that this guidance ignores the growing evidence that the third pathway plays an important role.

They demonstrate that studies, known as aerosols,–a microscopic version of a standard breathing droplet–float in the air for extended periods of time, potentially tens of feet. Even though they are 6 feet apart, each other endangers poorly ventilated rooms, baths, and other confined spaces.

Lidia Morawska, professor of atmospheric science and environmental engineering at Queensland University of Technology in Brisbane, Australia, said:

She raises a case in an open letter to the WHO accusing the UN agency for not giving the appropriate warning. A total of 239 researchers in 32 countries signed this letter. This letter will be published in a scientific magazine next week.

In an interview, experts rehearsed an aerosol transmission, but a diner at a Chinese restaurant and a choir member in the Washington State sat at separate tables.

WHO officials admit that the virus can be transmitted via aerosols, but it only occurs during medical procedures that can eject large numbers of small particles, such as intubation. .. CDC officials have not responded to multiple requests for comment.

In response to a question from The Times, Dr. Benedetta Allegrin, WHO’s top expert on infection control and control, responded to a question from The Times that Morauska and his group presented a theory based on laboratory experiments rather than evidence from the field. I said yes.

“We appreciate and value their opinions and contributions to this discussion,” Allegranzi wrote in an email. However, at the weekly conference call, the majority of the group of over 30 international experts advising WHO said, “The airborne transmission is an existing convincing enough to consider it to play an important role in covid-19 proliferation. I have not judged the evidence of.”

She added such an infection “will result in more cases and even more rapid spread of the virus.”

Since the first detection of the coronavirus in China in December, there has been a better understanding of how it spreads and the guidelines for the use of masks have changed.

Initially, the WHO and CDC said masks were overkill for the general public and should be preserved for health care workers. After that, the CDC recommended masks only for people with covid-19 symptoms.

Then, in April, after it became clear that asymptomatic people could spread the virus, the CDC proposed masks to everyone when physical distance was difficult.

With outbreaks now outbreaking and governors ordering new closures, almost every US state mandates or recommends face coverings, mainly to prevent the spread of the disease to the wearer.

Supporters of aerosol transmission can help prevent exhaled aerosols and inhalation of microscopic particles if the mask is worn properly. But they can also reduce the spread by improving ventilation and using UV light in the ceiling unit to blow air out of the room, they said.

Jose Jimenez, a chemist at the University of Colorado who signed the letter, said the idea of ​​aerosol transmission should not scare people. “It doesn’t seem like the virus has changed,” he said. “We think the virus has been transmitted this way all the time, and knowing about it helps protect us.”

He and other scientists cited research supporting the idea that aerosol transmission is a serious threat.

In mid-March, a study at the New England Journal of Medicine found that the virus was misted under laboratory conditions and remained “viable and infectious” for 3 hours. Said. In a real situation.

Some people, called “super spreaders,” are particularly good at exhaling fines, and it’s already been established that they produce 1000 times more than others.

A recent study found coronavirus RNA in the corridor near the patient’s room in covid-19 patients. Another raised concern for virus-laden aerosols was shed by the removal of personal protective equipment by floor cleaning equipment and health care workers.

Chinese researchers have found evidence of aerosols containing coronavirus at two hospitals in Wuhan.

The outbreak was among the choir members of Mount Vernon, Washington, and the incident at the Los Angeles Times, which initially raised the interest of some aerosol proponents. Of the 61 singers in the March 10 rehearsal, all but eight were sick, but did not use hand sanitizers and did not hug or hold. Two people died.

A team led by Sherry Miller, a professor of mechanical engineering at the University of Colorado, delved into the church hall blueprints, furnace specifications, choir locations, and attendance times. Researchers have illustrated the movement of a singer who was identified as the person who unknowingly carried the virus.

Aerosol inhalation was described in a paper written by the researcher as “the most likely transmission of infection during this event,” and sick people with common cold-like symptoms were among the many singer’s 6 It has been concluded that it was unlikely that they were spending time within feet or touching a surface common with them.

“The shared air in the fellowship halls and the massive emission of breathing aerosols from singing are believed to have been a significant factor,” the paper said.

Ultimately, a wide range of researchers, including some who studied the role of aerosols in the spread of influenza, SARS and other infectious diseases, participated in a campaign to raise awareness of aerosol transmission.

They said coronaviruses are less contagious in the air than measles, but as the risk of transmission increases, the air stagnates longer and people continue to breathe longer.

In an interview, they said the WHO authorities have improperly set higher standards than required for acceptance of the other two routes to indicate the spread of aerosols. “To them, the splashes and tactile sensations have proven to be very apparent, but airborne is so quirky that we need very high levels of evidence,” Jimenez said.

According to scientists, the evidence would require exposing many healthy people to the aerosols emitted by covid-19 patients.

The average person breathes 10,000 liters of air every day, said Donald Milton, co-author of the letter, a professor of environmental health at the University of Maryland and an expert on aerosols.

“Only 10,000 coronaviruses can infect 10,000 liters, and it’s very hard to find and prove that it’s there. This is one of the problems we had.” He said.

Category:
Coronavirus | News | Top Stories | US/World