Covid19 Airborne Transmission: Now What?
CDC (Center for Disease Control and Prevention) has finally released a statement that this virus is airborne.
Although there had been theories in the past months by the scientists that Covid-19 can be airborne, there was no clear statement to this matter and the general public may not be adequately warned.
Respiratory droplets are produced during exhalation like breathing, speaking, singing, and more strongly, by sneezing and coughing.
Droplets can be categorized into two:
Larger droplets are more visible like the ones that you see when someone coughs or sneezes and these immediately dissipate in the air because these are more weighty and easily fall to the ground.
Smaller droplets are smaller particles that dry quickly but stay longer in the air and can even travel in distances which is unknown yet as of this time.
How is this Corona Virus transmitted?
These are the three modes of transmission of this virus:
Contact Transmission - a transmission by direct contact with the infected person such as by touching an infected person by handshake or touching of surfaces or objects that are infected.
Droplet Transmission - a transmission by exposure to droplets (whether larger or smaller) from an infected person such as when one sneezes in close distance.
Airborne Transmission - a transmission by exposure to smaller droplets that remain suspended in the air in distances of more than 6 feet and for a longer time. This is now called an aerosol. The term “aerosol” was first used during the 2003 outbreak of SARS in Hongkong that was caused by the sewage system.
The efficiency of airborne transmission varies among the different kinds of viruses and bacteria. For example, pathogens from highly infectious diseases like tuberculosis, measles, and chickenpox are described as more efficient because these viruses and bacteria can spread rapidly both in close contact and longer distances.
When it comes to SARSCov2 or Covid19 virus, had it behaved like the measles virus, there would be higher and more rapid infection rates even during the previous earlier months and there is no sufficient evidence of efficient spread to people who enter a room hours after a Covid19 infected person was there.
How does airborne transmission occur for SARS-Cov-2 virus?
It is a known fact that this virus is mainly transmitted through close contact.
There are cases, however, that this virus infects through airborne transmission in the following circumstances:
Enclosed Rooms and Spaces – The virus spread when an uninfected person is exposed to an infected person either at the same time that they both in the same enclosed space or immediately after the infected person had left the room.
Prolonged exposure to respiratory particles – When there is an increased concentration of suspended respiratory droplets produced by expiratory exertion such as singing or shouting, there is a tendency for a higher rate of inoculum.
Inadequate ventilation or air handling – This is when there is a build-up of suspended small respiratory droplets and particles and there is not enough ventilation to exhaust the infected air.
Now how can we prevent the Covid-19 airborne transmission?
- Avoid enclosed rooms, especially crowded spaces as much as possible.
- These enclosed spaces must be re-engineered so that the build-up of pathogens can be lessened such as by exhaust fan installation.
- Maintain hand hygiene and disinfect surfaces.
- Wear masks and observe physical distancing.
Even if Covid-19 is airborne, its efficiency is not that much compared to other highly infectious diseases mentioned earlier. Medical experts and scientists describe its efficiency as somewhat like from the known common respiratory viruses like cough and colds. Besides, even if there is airborne transmission, your face masks will serve as a barrier to prevent a large amount of inoculum from entering into your body.