Thread by @AbraarKaran

1/ Transmission & infection are very complex dynamic processes

To cause clinical infection, need adequate dose of inoculum

Adequate dose depends on many factors, including
-proximity
-duration
-infectiousness of host
-symptomatology
-use of mask & which type
-ventilation

2/ Some of those factors are modifiable, but that depends on what you are capable of doing

You cannot control the infectiousness of random people around you, what viral strain they have, or what type of masks they have on (if any)

3/ You cannot (always) control the ventilation of space you are in (esp for necessities like travel or grocery shopping etc)

You can sometimes modify duration of time in a place or proximity to others, but often you cannot (public transit)

4/ To add to this, certain viruses require less of an inoculum dose to cause clinical disease

For instance, it is possible that Omicron would require less than Delta (epidemiologically we know it’s more transmissible)

So all of the modifiable factors become more important

5/ Our push for #BetterMasks is addressing one modifiable factor— the type of mask that you are wearing— because many of the other factors are going to be out of your control.

The more people that adopt it, the less the other modifiable factors will matter.