To what extent do masks protect against novel coronavirus infection? And then, is the virus transmitted with air flows? These questions have been answered thanks to a very recent study that will be published in the journal Clinical Infectious Diseases thanks to the work of a team from the University of Hong Kong (Yuen Kwok-yung et al, 2020).
Coronavirus, how the experiment was performed
The experiment was carried out by studying the transmission of the virus between hamsters. Infected hamsters with novel coronavirus and healthy hamsters were put in two different cages that had, on their surface, a lot of small holes. Then, a flow of air was directed with a ventilation system from sick to healthy hamsters. After 7 days 8 of the 12 healthy hamsters were infected with the virus with an infection rate of 67%. In the second part of the experiment the cage of the sick hamsters was covered with surgical masks and the infection rate, in this case, was 17% with two sick hamsters out of 12. Finally, another test was performed covering this time the cage of healthy hamsters with masks. In this case, the infection rate was 25% with 3 out of 12 sick hamsters. Not only that, what the researchers observed was that in the first part of the experiment, when no masks were used, the hamsters got sick earlier and showed more damage to lungs and trachea.
Coronavirus, the role of masks and air flows
What emerges from this experiment is that, first of all, the virus travels thanks to the air flows, therefore, the risk of contagion increases especially in closed rooms with air conditioning, where it is necessary to pay more attention to the social distancing and to wear the masks. Then, wearing masks helps reduce the risk of contagion by 40%. In addition to this, everyone should wear masks starting from the consideration that we could all be asymptomatic and able to infect other people. In fact, as has been shown by the experiment, the masks have proved to be even more effective if those who are sick wear them, since, in this way, the viral load is reduced by 10% compared to the case that wearing the mask are only the healthy ones. The amount of viral load, indeed, can determine a possible infection or not, that is, if the viral load is low then the risk of infection is also low. So in conclusion, scientists advise everyone to wear masks to protect themselves and others.