New research released by The International Air Transport Association (IATA) has concluded that there is a low risk of catching Covid-19 inflight as a result of the new safety measures airlines have put in place.
IATA’s research has identified just 44 cases of Covid-19 have been reported in which transmission is thought to have been associated with a flight journey. The number includes those cases before the widespread wearing of facemasks. The number is inclusive of confirmed, probable and potential cases. Over the same period of the 44 cases, IATA says “some 1.2 billion passengers have travelled”.
Dr. David Powell, IATA’s Medical Advisor says that
“The risk of a passenger contracting COVID-19 while onboard appears very low. With only 44 identified potential cases of flight-related transmission among 1.2 billion travellers, that’s one case for every 27 million travellers. We recognise that this may be an underestimate but even if 90 per cent of the cases were un-reported, it would be one case for every 2.7 million travellers.”
Dr Powell also points out that “the vast majority of published cases occurred before the wearing of face coverings inflight became widespread.”
The research is important because of widely reported cases where there has been infection of travellers where the new protocols were ignored.
Airlines have emphasised new safety measures including face masks, increased cleaning of aircraft and the HEPA filters on board which circulate clean air with a hospital-like efficiency. All of these measures are likely to be needed, according to other research.
For instance, next month The Journal of Emerging Infectious Diseases published by the Centres for Disease Control and Prevention is publishing an investigation of a Vietnam Airlines flight from London to Hanoi on March 2, 2020 (VN54) – the link below takes you through to the article.
It details how one passenger suffering from Covid-19 communicated the virus to at least 12 other fellow passengers in the business class cabin during the 10-hour flight.
Its conclusion is that, “…the risk for on-board transmission of SARS-CoV-2 during long flights is real and has the potential to cause Covid-19 clusters of substantial size, even in business class–like settings with spacious seating arrangements well beyond the established distance used to define close contact on airplanes. As long as Covid-19 presents a global pandemic threat in the absence of a good point-of-care test, better on-board infection prevention measures and arrival screening procedures are needed to make flying safe.”
Yet evidence is beginning to show that flying is safe, providing the new protocols, including facemasks, are observed. For instance, the Oxford Journal of Travel Medicine has the following article:
IATA’s research comes in a joint publication by Airbus, Boeing and Embraer of separate computational fluid dynamics (CFD) research conducted by each manufacturer in their aircraft.
While methodologies differed slightly, the manufacturers maintain that aircraft airflow systems do control the movement of particles in the cabin, limiting the spread of viruses.
Nevertheless, it seems face masks are an essential extra layer of protection.
Mask-wearing on board has been recommended by IATA since June and is now a common requirement on most airlines, following the implementation of the Takeoff Guidance by the International Civil Aviation Organization (ICAO).
“ICAO’s comprehensive guidance for safe air travel amid the COVID-19 crisis relies on multiple layers of protection, which involve the airports as well as the aircraft. Mask-wearing is one of the most visible. But managed queuing, contactless processing, reduced movement in the cabin, and simplified onboard services are among the multiple measures the aviation industry is taking to keep flying safe. And this is on top of the fact that airflow systems are designed to avoid the spread of disease with high air flow rates and air exchange rates, and highly effective filtration of any recycled air,” said Powell.
Airlines have also introduced measures such as limiting face-to-face interactions as passengers face forward and move about very little and on some airlines now have to request permission to use the washrooms (Ryanair). The design of aircraft means that the effect of the seat-back acting as a physical barrier to air movement from one row to another.
In addition, the minimisation of forward-aft flow of air helps, with a segmented flow design which is directed generally downward from ceiling to floor, as does the high rate of fresh air coming into the cabin. Air is exchanged 20-30 times per hour on board most aircraft, which compares very favourably with the average office space (average 2-3 times per hour) or schools (average 10-15 times per hour).
Finally, the use of HEPA filters which have more than 99.9 per cent bacteria/virus removal efficiency rate ensuring that the air supply entering the cabin is not a pathway for introducing microbes.
Boeing says that the design of the cabin and airflow system creates the equivalent of over 7 feet of physical distance between every passenger.
Meanwhile Embraer analysed the cabin environment considering a coughing passenger in several different seats and air flow conditions in its different aircraft, to show that the risk of onboard transmission is extremely low. The manufacturer said that “the actual data on in-flight transmissions that may have occurred, supports these findings.”