The corona virus is not only spread via droplet infection – it can also be transmitted through the air.
This is shown by a study from the University Hospital in Uppsala where the virus was found in the ventilation up in an attic.
– Then it can spread in the air in the ward as well, says Erik Salaneck, infection doctor at the hospital, to SVT News.
The discovery was made in April, when the corona pandemic seriously took hold of Sweden. Two doctors at the hospital were then up in an attic, far away from the covid patients, to try to find traces of the virus. Which they do, in an air filter.
– We have found it in the ventilation here, which is very worrying. If it can come up here, it can spread in the air in the department as well, says Erik Salaneck, to SVT Nyheter.
Found 60 meters away
The doctors also took samples from ventilation drums and air outlets in rooms where covid patients were cared for just over a week apart. The virus was found a few meters from the patients’ beds, up in ventilation openings in the ceiling and also inside the ventilation system. Viruses were found as far as 60 meters from places where covid patients stayed, according to the newspaper UNT.
To date, the coronavirus has been classified as a droplet infection, which means that it is spread through droplets that occur when an infected person coughs, sneezes, speaks or exhales. Drops can remain in the air for a while through so-called aerosols and in this way there is a small risk of infection via the air.
But the findings at the University Hospital , which have now been published in the scientific journal Scientific Reports, suggest that the virus may be airborne to a more significant extent.
– If it were just a pure droplet infection, with drops falling to the ground, we would not find it in the attic, says Erik Salaneck, who is one of the researchers who did the study.
Is airborne long enough
The researchers’ conclusion is that the virus is airborne in sufficient time to reach the ventilation. And Erik Salaneck is not surprised.
– No, I’m not surprised. Many viruses, including Sars and Mers, have shown this ability in some situations. Especially in care situations with sick people who secrete a lot of viruses, it can be in the air, he tells Aftonbladet.
Although the virus the researchers found was not active and contagious, they believe the discovery is important.
– Many factors, such as dehydration, may have reduced the virus’ ability to infect during the journey from the patients until we collected the samples many hours later. We also know that the infectivity in covid-19 is highest at the beginning of the infection, but those who were cared for at the infection clinic had usually been ill long before they got there, says Erik Salaneck to UNT.
Advice: Look at mouth guards
The discovery in the study is consistent with other previous studies according to Salaneck. And it is important for how people should protect themselves from being infected, says Erik Salaneck. He believes that the Swedish councils and guidelines differ from other countries on this point.
– There are many things we do right and well. We try to increase social distancing, but the difference is that others recommend mouth protection in social situations outside healthcare. I think you have to keep looking at that. Our study is consistent with other studies. Among other things, it has been shown with computer modeling that it can be spread in the air, says Erik Salaneck to Aftonbladet.
However, he does not want to say if or how he thinks the Swedish Public Health Agency should formulate its advice and guidelines.
– It can be stated that the Public Health Agency’s guidelines differ from others. It is not our responsibility as researchers to design policies.
Tegnell: Is an exception
The Public Health Agency’s state epidemiologist Anders Tegnell does not think that the new study presents anything that makes the agency need to change its current assessment.
“Exceptions exist as with all infections, you can certainly in special situations cause an aerosol that can be spread a little longer but there are no cases described when you have infection spread via ventilation systems etc. as with the real airborne infections”, writes Anders Tegnell in an email to SVT News.