NEW YORK (AP) – In a lab at a University of Maryland, people infected with the new coronavirus sit on a chair and place their faces at the end of a large cone. They recite the alphabet and sing or just sit quietly for half an hour. Sometimes they cough.
The cone sucks everything out of their mouths and noses. It’s part of a device called “Gasundite II” that helps scientists study one big question: How does the COVID-19 virus just spread from one person to another?
It clearly moves on small liquid particles sprayed by an infected person. People expel particles when coughing, sneezing, singing, screaming, talking and breathing. But the drops come in different sizes, and scientists are trying to pin down just how dangerous the different types are.
The answer affects what we should all do to avoid getting sick. That’s why a few days ago when the US Health Agency seemed to have changed its position on the issue, but later said that it was in the headlines. It mistakenly published a new language.
The recommendation to stay at a distance of at least 6 feet (2 meters) – some officials cite about half of this distance – is based on the idea that large particles can go very far before they fall to the ground. They are like drops of spritz from a window cleaner, and they can infect someone’s nose, mouth or eyes by inhaling or inhaling.
But some scientists are now focusing on thinner particles, which spread more like cigarette smoke. It is caused by the warmth of our body through the air cells and the drafts above. They linger in the air for minutes to hours, spread throughout the room and can form if ventilation is poor.
The potential risk is breathing them. Measles is spread this way, but the new coronavirus is much less contagious than that.
For these particles, the so-called aerosols, “6 feet is not a magical distance,” says Lincoln Merr, a leading researcher who studied them at the Virginia Tech in Blairburg. But he says it’s still important to keep your distance from others, “better”, because aerosols are most concentrated near the source and pose a greater risk at closer distances.
Public health agencies have generally focused on larger particles for coronavirus. He asked more than 200 other scientists to publish the request Consider the potential risk of aerosols in July. The World Health Organization, which has long denied the risk of aerosols, except in the case of certain medical procedures, said later. Aerosol transmission of coronavirus cannot be ruled out in cases of infection within spaces with congestion and poor air circulation.
U.S. Department of Disease Control and Prevention The issue came to the fore recently when the centers posted statements highlighting the idea of aerosol spread on its website and then deleted it. The agency said the posting was an error and the statements are just a draft of the proposed changes to its recommendations.
Dr Jay Butler, CDC’s deputy director for infectious diseases, told the Associated Press that the agency said large and heavy drops that come from coughing or sneezing are the primary means of transmission.
Butler said at a scientific meeting last month that current research suggests it is possible to spread an aerosol of coronavirus, but people do not think this is the main way to get infected. Further research could change that conclusion, and he urged scientists to study how often coronavirus aerosol spreads, what circumstances make it more probable, and what reasonable steps can be taken to avoid it.
Murray said he thinks being infected by aerosols “happens a lot more than people are initially willing to think.”
As the main piece of evidence, Mar and others point to so-called “superspider” incidents where an infected person apparently passed the virus to many people in the same setting.
In March, for example, after a coronavirus symphony member rehearsed in Washington state, room 2 other people were found sitting throughout the room. Infected and two died. In a crowded and poorly ventilated restaurant in China in January, the virus was clearly spread The aerosols were spread by air conditioner for five people from the lunch time patron on two adjoining tables in a pattern indicating. Also in January, passengers on a Chinese bus became infected 23 others, many of whom were scattered around the vehicle.
Butler said such incidents are worrying about the spread of aerosols but do not prove it happens.
There may be another way to disperse smaller particles. William Ristonpart of the University of California at Davis said they may not come straight from anyone’s mouth or nose. Its research Saw that if the tissue of the paper is seeded with the influenza virus and then crushed, they give the virus tolerated particles. Therefore, people with a covid-19 should be sure to wear a mask when disposing of discarded tissue waste, he said.
Scientists warning about sci rosols say the current recommendations still make sense.
It’s still important to wear a mask, and make sure it fits the snail. Keep washing your hands diligently. And again, these would mean that you have to spend for these processes. Avoid crowds, especially indoors.
Ventilation is one of their main recommendations to avoid the formation of aerosol concentrations. Therefore, researchers say, stay away from ventilated rooms. Open the windows and doors. Anyone can use air-purification devices or virus-inactive ultraviolet light.
Best: Just do as much as you can outside, where dilution and the sun’s ultraviolet light work in your favor.
“We know it’s a very stunningly effective move from the outside,” says Jose-Louis Jimenez of the University of Colorado-Boulder. “It’s not impossible to get infected outside, but it’s difficult.”
Researchers say different precautions should be used in combination rather than just one at a time. In a well-ventilated environment, “6 feet (separation) is great if everyone gets a mask,” and no one stays directly under an infected person for too long, says Dr. Maryland School of Public Health. Says Donald Milton. , Whose lab has a Gasandhite II machine.
The duration of exposure is important, so there’s probably no greater risk when passing a jogger on the sidewalk or masking a short elevator ride, experts say.
Scientists have published tools online tools To calculate the risk of airborne outbreaks in different settings.
However, at a recent meeting about aerosols, Ge George Benjamin, executive director of the American Public Health Association, noted that preventive measures in the real world can be a challenge. It can be difficult to stay away from others in homes with many generations. Some older buildings have windows that had a “nail that was closed years ago.” And “We have so many communities where they don’t even have access to clean water to wash their hands.”
While it would seem strange for all the scientific prowess to study the new coronavirus, the details of how it spread nine months later may still be in doubt. But history suggests patience.
“We’ve been studying influenza for 102 years,” says Milton. “We still don’t know how it was transmitted and what the role of aerosols is.”
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The Associated Press is supported by the Department of Health and Science From the Department of Science Education at Howard Hughes Medical Institute. AP is fully responsible for all content
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