Originally Posted by
esscee
Most aircraft the cabin air consists of 50% recirculated air already been used in the cabin. So it will be interesting to see what if anything is done by Regulators/Manufacturers/Airlines to keep the recirculator fan filters in better condition. Maybe change the filters more often than they do at present?
The funny thing about the filters is that they filter out more stuff the dirtier they get, at least for a while. The reason it makes sense to change them is that your fuel burn goes up as they get dirtier. If your are worried about bacteria then you need to disinfect as they can grow on the medium. However, viruses need a host, so you aren't as bad off.
Airflow in cabins is very complex, but in general you are mostly affected by those around you. So if the infection rate is 20/100k a flight of 350 people will have <<1 (0.07) case. The risk on the aircraft in these cases isn't really to other travellers, but to the crew. If you are limiting to people without symptoms you will get a lower number of infectious people. If everyone then monitors themselves/is monitored you have the ability to isolate them quite effectively. The premise of 14-day quarantines is that you are expecting numbers to be much higher than 20/100k. "High" infection rates are a very safe assumption right now, but might not hold in 4-18 months. SARS-CoV-2 is more infectious than SARS-CoV-1; therefore, harder to contain. However, it isn't impossible. What is does require is significant coordinated action, and a risk averse attitude.