Understanding Covid Transmission

It has been understood since 2020 that Covid is airborne, the virus is aerosolised when someone infected breathes out. It is like smoke, it stays in the air for hours. Public health messaging, has, and continues to obfuscate this. Many people still believe that hand sanitising, surface disinfecting and maintaining social distance are useful measures.

Hand washing and blue surgical masks are a product of what is called ‘droplet theory’. This is the idea that the virus is exhaled when you cough or breathe hard and falls to the ground or surfaces within about a 2m radius.

Just to be clear - this messaging is deliberate, hand sanitising is about personal responsibility, you are responsible for your own safety. Air cleaning puts the responsibility and liability squarely on the owner of the space, ie businesses.

You get infected with Covid through being in shared air space. It is really easy to understand, just think about people smoking in a room.

The variables are the size of the space, air circulation, density of people and time spent. Illness is about viral load - which just means how much virus you inhale. Even if you can’t avoid being in a risky space, the less virus you inhale the better. Just because a room is empty when you enter doesn’t mean the virus is not still in the air from previous occupants. Outside transmission is rarer but not impossible, again just think about someone smoking.

You are not going to catch covid from shaking someone’s hand or giving them a hug, you are not going to catch it from touching a door handle (these things are not technically impossible but vanishingly unlikely).

Finally, risk is not binary. If you have to go to work in an office where no-one masks and there is no clean air mitigation, and you don’t feel like you can wear a mask there, it still makes sense to wear a mask on the train. Each situation is a separate chance to inhale virus, if you don’t mask on either you double your risk.

The only reason not to mask in a setting where you don’t know anyone, say a train or plane, is that you believe you are going to get infected from time to time anyway so it just isn’t worth constantly thinking about Covid because that makes life miserable, but this really stems from not properly understanding the risk. Again, if HIV was airborne and going to a pub meant you could get infected with HIV, you would not go to the pub. If it meant you would go home and infect your children with HIV you definitely would not go into the pub. So it is just that you don’t understand that Covid is airborne and acts on the body in a similar way to HIV.