The new coronavirus can spread by air to people who are more than six feet from an infectious person, the United States Centers for Disease Control and Prevention said on Monday, in guidelines that could raise serious concerns. new challenges for the safe reopening of businesses and schools.
In an update to its website, the CDC said the coronavirus can sometimes spread through small particles that can linger in the air and infect people separated by distances previously considered safe. Many social distancing guidelines adopted by workplaces, restaurants, and stores advise people to stand at least 6 feet (1.8 meters) from each other to avoid transmitting the pathogen responsible for the disease. Covid-19.
“Today’s update acknowledges the existence of some published reports showing limited and rare circumstances where people with Covid-19 infected others who were more than six feet or less away long after the Covid-19 positive person leaves an area, “the agency said in a statement. Press release.
The change follows months of mounting scientific evidence that Sars-CoV-2 can be transmitted through the air at distances greater than those included in the early stages of the pandemic. There were indications that the CDC was preparing to update its guidance. Last month he published and then deleted an airborne transmission directive, later describing it as a draft published in error.
New direction comes as pandemic appears to move to a more intense phase in the United States In 34 states, the seven-day average of new cases is higher than a month ago, and an outbreak of the virus at Home Blanche seems to widen. At the same time, schools are reopening, states like Florida have lifted restrictions on restaurants and other businesses, and the approach of cooler weather and vacations should push more people indoors to socialize.
Ventilation problems
A recent archived version of the CDC’s webpage made no mention of airborne transmission, pointing out that the main way the virus is spread is through close contact between people who are within six feet of each other. , through respiratory droplets emitted by coughing, sneezing and speaking. . He acknowledged that the virus could be spread by other means, including on contaminated surfaces.
The updated CDC site includes a section acknowledging that viral particles sometimes spread through the air, especially in enclosed spaces with poor ventilation. Scientists believe that in these cases, the airborne viral particles emitted “became concentrated enough to transmit the virus to other people”, sometimes including shortly after the infectious person left.
Transmissions sometimes occurred when the infected person was breathing heavily, singing or exercising, the agency said.
Linsey Marr, an aerial virus transmission expert at Virginia Tech, in a tweet called the update “a precise and much-needed update recognizing the aerial spread and the importance of masks at all times around others and people. ventilation”.
In an open letter in July, 239 scientists urged the World Health Organization to recognize the potential for airborne spread. A study on a meat factory suggested that under certain conditions the virus can travel 6 meters.
Unchanged recommendations
At a Senate hearing last month, CDC Director Robert Redfield admitted there was evidence of airborne spread, but said the CDC document that was withdrawn had not been cleared to be published by agency staff.
“I just want to point out for the American public and everyone here that this document that was released was a draft, had not been technically reviewed by the CDC,” Redfield said on September 23. He said the agency had reverted to the one that had been reviewed.
The CDC on Monday reiterated that it is more common for the virus to be spread through close contact with an infected person. The update does not change the CDC’s recommendations on how to protect yourself from infection by wearing masks, staying 6 feet away, washing hands, cleaning surfaces and staying at home by case of illness.
“The CDC’s recommendations remain the same based on existing science and after a thorough technical review of the guidance,” the agency said in a press release sent to reporters on Monday.
It is unusual for the CDC to alert the media to changes in its guidelines, with updates frequently posted to the agency’s website with little fanfare.
The agency did not immediately respond to an emailed question about whether the acknowledgment would result in changes to guidelines for restaurants, businesses and other settings.
(Except for the title, this story was not edited by GalacticGaming staff and is posted from a syndicated feed.)