Risk of infection with exhaled air with covid-19 is confirmed by study
Researchers from the American University of Nebraska have just shown that the virus found in the air that patients breathe is undoubtedly infectious.
This is a rather disturbing finding regarding the spread of the Covid-19 epidemic. For the first time, researchers have been able to demonstrate that the aerosolized viral particles are intact enough to replicate and cause infection.
Researchers from the University of Nebraska have replicated Sars-Cov-2 particles collected from the rooms of patients with the disease. If we already know that the disease is transmitted through droplets expelled by coughing or sneezing, this discovery shows this time that contamination can also occur through droplets released into the air when a person speaks or even breathes. Light, these drops remain suspended in the air for a long time without ventilation. These findings have been published on the site medrxiv.org.
Validate the method
At the moment, these first results are preliminary and have not yet been validated by the scientific community. The latter must confirm the validity of the method used by the researchers. According to the lead author of this study, his previous research examining the presence of the virus in the air in patients' rooms in hospitals is expected to be published shortly in a scientific journal.
Regarding this study, Joshua Santarpia, a professor at the University of Nebraska Medical Center, explained that the method of collecting viral particles in the air, using a device the size of a cell phone, was not easy to configure. "The concentrations are low, there is generally little chance of recovering usable samples." To reach these conclusions, the scientists took air from the rooms of five bedridden patients, 30 centimeters from their feet. Scientists have managed to collect microdroplets less than five microns in diameter that contain viruses, and even less than one micron.
"There are infectious viruses in the air"
Then the scientists isolated the virus and then put it in a special medium for it to replicate. The researchers managed to replicate three of the eighteen one-micron droplet samples. "It replicates in cell culture and is therefore infectious," says Joshua Santarpia.
And then, to continue: "The debate has become more political than scientific, I think that most infectious disease specialists agree that the airway is a component of transmission, although we are still debating its importance." Quoted by numerous media outlets, Professor Linsey Marr, a specialist in airborne virus transmission, commented on Twitter that this study presented "solid evidence." She added: "There are infectious viruses in the air. It remains to be seen how much you have to breathe to get infected."
Although at the beginning of the worldwide Covid-19 epidemic, this transmission by air was considered impossible, since then many scientists have revised its copy. Starting with the World Health Organization. On July 7, he admitted that air transmission would not ultimately be ruled out. "We recognize that evidence is emerging in this area and therefore we must be open to this possibility and understand its implications," Benedetta Allegranzi, a WHO official, said at a remote news conference.
In a letter published in the Oxford Clinical Infectious Diseases journal, more than 200 international scientists had urged WHO and the international medical community to "recognize the potential for Covid-19 airborne transmission." For the time being, however, direct contamination remains the main route of contagion.