A Chinese study has suggested that air conditioners may spread the coronavirus (koronavirus, in Finnish).
The was study published on the Centers for Disease Control and Prevention (CDC) website and approved by the Ethics Committee of the Guangzhou Center for Disease Control and Prevention.
The scientists looked at 10 coronavirus cases from three families who ate at a restaurant at the same time in Guangzhou, China.
In late January, the first coronavirus patient in the case arrived from Wuhan to Guangzhou with his family and ate lunch at a restaurant with three family members. The other two families ate less than a meter away at other tables.
The windowless restaurant had an air conditioning vent on one side of the room and a vent on the other. The three families dined in the restaurant for around an hour in close proximity.
Later that day, the first patient developed symptoms suggestive of a Covid-19 and went to a hospital where she received a positive corona test. On 5 February nine members had contracted Covid-19 disease of the three families who had eaten at very close tables.
Among the 83 customers that day, 10 became ill with Coronavirus; the other 73 were identified as close contacts and quarantined for 2 weeks. During that time, both the air conditioner and the quarantined customers tested negative for coronavirus.
According to the research team, the only possible exposure to the virus for the other two families would have occurred in the restaurant.
The researchers admit that there are shortcomings in the study and they have not re-tested what kind of ventilation route the air conditioner in the restaurant would create.
Sambuddha Chaudhuri, an epidemiologist at the Indian Institute of Technology Bombay (Mumbai) talked to The Print and said, “This virus is not airborne in the same way as viruses that cause common cold and flu. It is just that if a person sneezes, a thick spray gets created — that is when a virus is in the air. But it does not float around in the air — it settles on surfaces and can stay there for a very long time. Since it does not stay suspended in the air for a very long time, air conditioners should not be a threat especially if it is in your own house where no one is infected.”
On the other hand, Professor Kari Reijula of the Faculty of Medicine at the University of Helsinki Italked to Helsingin Sanomat and said, “Regarding the spread of the virus and infections, the general position in the research community is that the virus does not spread primarily by air.”
Reijula estimates that airborne infection is not a typical way for coronavirus to spread, although, in theory, it is possible.
According to him, “When an infected person coughs, due to the aerodynamic properties, particle size and weight of the particles and droplets carrying the coronavirus, the droplet does not remain in the air for a long time. As a result, the virus is mainly transmitted from hand to mouth rather than by inhaling the droplet that carries the virus.”