The scientists varied the concentration of carbon dioxide in the air chamber from 400 parts per million (ppm) to 6,500 parts. At the same time, they observed the behavior of airborne viruses in this environment. The results showed that with an increase in the amount of CO2, viruses remain contagious longer. This also applies to the SARS-CoV-2 virus, which caused the pandemic.

Thus, the level of 800 ppm led to an increase in the air resistance of the virus. At a level of 3000 ppm (this is observed in a crowded room), 10 times more viruses were stored in the chamber than in clean air.

The study helped to better understand how to deal with the spread of infections. The scientists stressed that conventional ventilation is very effective, since under the influence of fresh air, viruses are inactivated faster.

Scientists also recalled that the level of carbon dioxide in the Earth's atmosphere is growing rapidly. It is projected to reach 700 ppm by the end of the century. This will affect not only the environment, but also the likelihood of future pandemics.