Inflight COVID-19 transmission is rare, not only due to new measures but thanks to the airflow within aircraft

Since the start of 2020 up to October, there have been 44 confirmed or possible cases of COVID-19 associated with a flight. In that period, some 1.2 billion passengers have traveled. That equates to one case for every 27 million travelers. Dr. David Powell, IATA’s Medical Advisor, calls the figures “extremely reassuring.” “Furthermore, the vast majority of published cases occurred before the wearing of face coverings inflight became widespread,” he notes.

Aligned data

Studies by Airbus, Boeing, and Embraer explain the reasons behind the low transmission rate. Though aircraft types vary, detailed simulations confirmed that aircraft airflow systems effectively control the movement of particles in the cabin, limiting the spread of viruses.

High Efficiency Particulate Air (HEPA) filters, the natural barrier of the seatback, the downward flow of air, and high rates of air exchange efficiently reduce the risk of transmission.

HEPA filters, for example, have a more than 99.9% bacteria/virus removal efficiency rate, ensuring that the air supply entering the cabin is not a pathway for microbes. Air is exchanged 20-30 times per hour on board most aircraft, which compares very favorably with the average office space (average 2-3 times per hour) or schools (average 10-15 times per hour).

Mask wearing adds an extra layer of protection and is now common on most airlines. The Takeoff Guidance issued by ICAO supports this approach. The guidance also adds numerous other layers of protection to keep transmission rates to a minimum.

Manufacturer Studies

The simulations carried out by the three major manufacturers further highlighted the importance of aircraft design in low infection rates. An Airbus simulation of the air in an A320 cabin calculated parameters such as air speed, direction, and temperature at 50 million points in the cabin, up to 1,000 times per second. The same tools were then used to model a non-aircraft environment, with several individuals social distancing. The result clearly demonstrated that potential exposure was lower on an aircraft than when staying six feet apart in an office or classroom.

Boeing researchers studied various scenarios, including a coughing passenger with and without a mask seated in various locations, and different on/off variations of overhead air vents.

Embraer research likewise showed that risk of onboard transmission is extremely low, and the actual data on in-fight transmissions that may have occurred supports these findings.

Safety first

The research done on inflight transmission of the coronavirus shows the cooperation and dedication to safety of all involved in air transport, providing undeniable evidence cabin air is safe.

Indeed, the priority on safety is no different during the COVID-19 outbreak. A recent IATA study found that 86% of recent travelers felt that the industry’s COVID-19 measures were keeping them safe and were well-implemented.

Alexandre de Juniac, IATA’s Director General and CEO, accepts that there is no “single silver-bullet measure” that will make air travel 100% safe in the age of COVID-19. “But the combination of measures that are being put in place is reassuring travelers the world over that COVID-19 has not defeated their freedom to fly,” he says. “Nothing is completely risk-free. But with just 44 published cases of potential inflight COVID-19 transmission among 1.2 billion travelers, the risk of contracting the virus on board appears to be in the same category as being struck by lightning.”

Image credit | Getty