9.5 million people traveled on airplanes in the United States during the 2020 Thanksgiving holiday. Given that the SARS_CoV-2 is an airborne virus, what is the risk of contracting COVID-19 on a plane?
How is the air on planes filtered?
50% of plane air is fresh from outside the cabin (assumed to be sterile). The other 50% is filtered through a High Efficiency Particulate Air (HEPA) filter which removes up to 99.97% of particles in the air, lowering the risk of airborne transmission. Although the HEPA filters take out more than 99% of air particles these filters are not protective if you are in close proximity to an infected individual. This is why wearing masks and following airline precautions is essential to preventing the spread of COVID-19.
What does the research say?
One study found that a symptomatic COVID-19 patient boarded a flight with 217 people and spread it to 16 individuals. Of those infected, 12/16 were sitting in business class with the symptomatic patient. No one on the flight was wearing masks.
In March, 299 asymptomatic individuals were evacuated from Italy on an 11-hour flight to South Korea. Passengers on this flight wore N95 masks except during meals. On arrival, 6 asymptomatic passengers tested positive for SARS-CoV-2. One individual developed COVID-19 symptoms and tested positive during the 14-day quarantine period. She admitted to taking off her mask when using the restroom on the flight. The most plausible explanation is that she became infected while using the toilet.
If you decide to travel:
- The CDC states that the safest way to protect yourselves and others from COVID-19 is to not travel
- If you do travel, check state and local requirements at the link in the description before you travel.
- Get tested 1-3 days before your flight and 3-5 days afterwards.
- There is also still a risk of getting COVID-19 traveling to and from the airport and while at the airport.
- Remember to follow CDC guidelines of social distancing, mask wearing, and hand washing.