IATA reiterates risk of Covid-19 transmission onboard commercial aircraft remains low despite two recent published reports suggesting potential in-flight spread

24 September, 2020

The International Air Transport Association (IATA) has reiterated its previous assertion that the risk of infection while travelling onboard a modern commercial aircraft remains low despite the recent publication of two studies that suggest some form of person-to-person transmission of Covid-19 between passengers.

The industry body references the incidents of onboard transmission in its 'Medical Evidence for Possible Strategies' guidance, but stands by its belief that the data supports conclusions that the risk of onboard transmission of the virus remains low.

The association is advocating layered approach for travellers to take additional precautions to further lower the risk with guidance to wear a mask or face covering providing significant protection to all onboard. Passengers are also encouraged to practice good hand hygiene and avoiding touching the eyes, nose or mouth, especially after contact with commonly touched surfaces.

An increasing spotlight on the risk on infection while travelling on commercial aircraft has been placed on the industry as more media reports carry news on the publication of the research which investigates specific incidents on studied flights between London and Hanoi and between Boston and Hong Kong.

As reported by Forbes, the first of these studies is from Vietnam's National Institute of Hygiene and Epidemiology (NIHE) and appears in the Nov-2020 edition of the journal Emerging Infectious Diseases.

The NIHE scientists investigated a cluster of cases among passengers on a Vietnam Airlines flight from London to Hanoi on 02-Mar-2020. The researchers traced the 217 passengers, crew members and close contacts (anyone who had come within two meters for more than 15 minutes).

The researchers identified 16 people who became infected with the novel coronavirus. Twelve of those were passengers seated in business class along with "Case 1," the only symptomatic person on board the flight. The other four infected people - including Case 1's sister - were personal contacts who came into close proximity with infected passengers between the flight's arrival and the quarantine period. As such the researchers acknowledged that "seating proximity was strongly associated with increased infection risk".

The second case, highlighted by the Centers for Disease Control and Prevention and also appearing in the same issue of Emerging Infectious Diseases conducted by scientists from a multi-national group of institutions, including the London School of Hygiene & Tropical Medicine, University of Hong Kong, and others, also revealed likely transmission during air travel.

The researchers investigated a cluster of two passengers and two cabin crew members on the same 15-hour flight from Boston to Hong Kong on 09-Mar-2020, all of whom were asymptomatic at the time of the flight but tested positive for Covid-19 within five to 11 days later. They discovered their virus genetic sequences were "identical, unique, and belong to a clade not previously identified in Hong Kong," strongly suggesting that the virus was transmitted during the flight as the "only location where all four persons were in close proximity for an extended period was inside the airplane".

IATA says it continues to "keep an open mind and a close watch on emerging data and medical literature" but notes that the two flights in question took place in the early stages of the pandemic and "a lot has taken place" since then, most notably face masks and face coverings now common practice during flights and other environments where social distancing is not possible.

"There have been millions of flights since the start of the COVID-19 outbreak. And there are very few reported incidents where onboard transmission is suspected. We believe that the data is telling us that the risk of onboard transmission of the virus is low when compared with other public indoor environments, such as trains, buses, restaurants and workplaces," it says.

While the airline industry and IATA continue to highlight flying as a low-risk activity during the ongoing coronavirus pandemic, these two international studies - and more significantly the media attention around them - could influence traveller sentiment on the risks of taking a flight.

Traveller sentiment and travel restrictions continue to severely dilute passenger demand, especially when it comes to international and long-haul routes, many of which remain grounded due to government curbs. IATA has this week called for a new regime of systematic testing for all international travellers before departure.

This, it says, "should enable governments to safely open borders without quarantine". As important, it will also provide passengers with the required certainty that they can travel without having to worry about changing government rules or potential infection.

"Quarantine measures are killing the industry's recovery," says IATA's director general Alexander de Juniac, citing a recent 11-market survey where more than four in five travellers (83%) said that they will not travel if there is a chance of being quarantined at their destination. "That is a very clear signal that this industry will not recover until we can find an alternative to quarantine," adds Mr de Juniac.

It is not an easy solution though, and is one that appears unfavoured at government level. It will require the integration of systematic testing into the travel process, a potential logistical challenge and a major impact how people travel. It will need testing manufacturers to develop tests that can be deployed that are fast, accurate, scalable, affordable and easy to use. It will also need governments and health authorities to agree on common standards so that tests administered in the departure country are accepted on arrival. Three major hurdles that may be difficult to clear.