How high is the risk of contracting COVID-19 from an infected person on the airplane?
We address your burning questions regarding virus transmission inflight.
Q1. I am stuck in a confined cabin with other passengers for long hours, what is the risk of inhaling contaminated air as it circulates throughout the plane cabin?
To answer this question, it is good to understand the ventilation system in the plane.
- The flow pattern of air is compartmentalized into various sections on the aircraft.
- Air flows from top to bottom, rather than front to back.
- Each of these sections receives air from overhead distribution nozzles that flows through the length of the cabin. The air exits the plane through a grill that is often located beneath the windows, or where the sidewalls meet the floor of the plane.
- This air then combines with the air outside before going through a HEPA (High Efficiency Particulate Air) to clear away dust and microbes before re-entering the plane.
- The number of these ventilation zones varies depending on the aircraft, but each zone typically goes through this filtration process 15 to 30 times within the hour, with 50 percent of the air getting re-circulated and 50 percent of the air coming from outside.
- HEPA filters in the aircraft are able to filter out majority of viruses and bacteria.
These filters have similar performance to those used in hospital operating rooms and are effective at capturing >99% of the airborne microscopic particles (eg. bacteria and viruses) in the filtered air.
Q2. Will I be infected if I were on the same flight as a case of COVID-19?
It is not easy to catch an infection unless the infected passenger is seated within two rows from your seat and is actively coughing or sneezing without a mask.
Q3. Will I be infected if an infected passenger walks past my aisle seat?
Transient exposure to an infected passenger passing by your seat along the aisle is considered a low risk encounter. However, if the infected passenger were to sneeze or cough and the respiratory droplets fall on your tray / arm rest, there is a risk of transmission.
Q4. Is there a “safer” place to sit in the plane to prevent getting infected?
To minimise contact with other passengers, you can consider picking a window seat and stay put. A study done in 2018 showed that people on windows seats are exposed to fewer passengers because they leave their seats less often than those sitting near the aisle. However, it is still important to do some calf exercises and stretching to prevent Deep Vein Thrombosis related to long haul flights.
Q5. What can I do to reduce the risk of being infected with COVID-19?
- Please practise good hand hygiene at all times.
- The most common mode of transmission is still via respiratory droplets on contaminated surfaces.
- Keep a small hand sanitiser in your cabin bag.
- You can consider bringing alcohol wipes to clean surfaces including seatbelt bucklers, tray tables, control sets and armrests.
- Avoid touching your face.
Q6. Shall I still take the flight if I am having flu symptoms or starting to develop a fever?
If you are not well before a flight, you should consult a doctor for a clinical examination. The doctor can assess your fitness to board the flight. If you are assessed to be unwell, the doctor can write a memo regarding the need to postpone the flight. In view of the current COVID-19 situation, if you are having a fever, it is best not to travel overseas.
Q7. What else should I know before I travel?
It is important to purchase a valid travel insurance before your trip. Please check if your travel insurance covers any treatment related to COVID-19 infection.
Travelling soon? You may want to consider getting a vaccination at least 4 weeks in advance and stock up on some travel medication. Not sure what to be vaccinated against or what kind of medicine to bring? Teleconsult a GP anytime to seek travel health advice.