Lets start with a few facts. Since the beginning of 2020 there have been 44 cases out of 1.2 billion passengers where Covid 19 has been associated with air travel. That works out to one in twenty seven million. Most of these cases occurred before it was mandatory to wear facemasks (except when eating).
Dr David Powell IATA Medical Director called this “ Extremely reassuring” .
Studies have been conducted by Airbus , Boeing and Embraer which help explain the low numbers. It is the Airflow systems in aircraft. The systems differ but the overall findings remain constant. High Efficiency Particulate Air (HEPA) filters , the natural barriers of seats backs and the high rate of air exchange efficiently reduce the chance of transmission. HEPA filters have a 99.9% bacteria removal efficiency. This ensures the air is not a pathway for microbes. The rate of air swap is high usually 20-30 times per hour this compares favourably with offices 2-3 times per hour and schools 10-15 times per hour.
The wearing of masks adds an extra layer of protection.
An Airbus simulation of a A320 where they took readings at 50 million points in the cabin and found that in an aircraft cabin it is safer than an office where social distancing of 6 feet was practised.
Boeing has also conducted research using different scenarios with a coughing passenger in different seats with and without overhead airvents in operation which concluded that transmission rate is very low.
Airlines and airports are moving towards Covid 19 testing to encourage air passengers to return. Once vaccinations commence, we will see a quick return to international travel, starting with short haul flights and later to the long haul markets.
Information taken from IATA Annual General Meeting 2020 magazine