Is it safe to fly — what are the odds of you catching Covid-19 on a plane?

As airlines have started resuming operations, there has been no shortage of positive information reassuring potential travellers of the safety of air travel despite the ever-present reality of Covid-19. 

We have been informed about the safety measures and protocols that various airlines have implemented, including the benefits of high-efficiency particulate air (Hepa) filters, social distancing protocols, contactless processes and the absence of in-flight magazines. But just how safe is it really to travel via air?

At the beginning of October, the International Air Transport Association (Iata) released new information based on figures released by Airbus, Boeing and Embraer. According to them, only 44 travel-related cases of Covid-19 were identified out of a sample of 1.2 billion travellers since the start of 2020 — or one out of 27 million travellers.

Acknowledging that travel isn’t risk-free, Alexandre de Juniac, Iata’s director-general and CEO, compared the risk of contracting Covid-19 to the same chances as “being struck by lightning”.

The findings of a report by Harvard researchers with the Aviation Public Health Initiative concurred. 

Released this week, it stated that provided proper ventilation and other protective measures were in place, the risk of Covid-19 being spread on-board a plane was lower than “that of other routine activities during the pandemic, such as grocery shopping or eating out”. 

MATRIX OF PREVENTIVE MEASURES

Guy Leitch, an aviation analyst and pilot, says he has seen no credible claims or evidence to indicate a dangerous level or risk of infection in international airline travel.

According to Leitch, the level of safety when it comes to Covid-19 infections and airline travel cannot be attributed to any one thing: you have to consider the whole matrix of preventive measures put in place to reduce infection rates on aircraft.

“We heard a couple of months ago already about how effective the airline ventilation and air cleaning systems are, particularly the use of Hepa filters,” says Leitch, referring to claims that the quality of air within an aircraft is on par with that of operating theatres.

“[But] it all starts long before the passenger even gets on the aircraft,” he says, referring to the fact that many international airlines require passengers to produce a negative Covid-19 test taken within 72 hours (sometimes 96 hours) of departure before boarding.

“On top of that, there are temperature checks as you enter the terminal buildings and people are being forced to wear masks. The airlines have been very rigorous, as have the airports, in imposing the necessary health precaution protocols to stop the infection even getting onto the flights.”

The Hepa filters on an aeroplane also assist in keeping the air virus-free.

Leitch explains: “They are ventilators from the top downwards. In other words, the air flows out of the cabin vents literally above the passengers’ head and back out the aircraft or through the Hepa filters from vents under the seats. So there is very little lateral, sideways spread of the air.

“Even if you were infected and you were breathing out the virus it wouldn’t really have a chance to spread to the people next to you; it would simply be blown down to the floor and ejected.”

CAUTION STILL NEEDED

The need to exercise caution is not diminished, however. In an article published by the Journal of Travel Medicine at the end of September, the authors note that the absence of large numbers of confirmed in-flight Covid-19 transmissions “is encouraging but is not definitive evidence that flyers are safe”.

A report recently published in Eurosurveillance, the journal for the European Centre for Disease Prevention and Control, is one of very few detailing the possibility of Covid-19 transmission during air travel.

According to the authors, 59 confirmed cases of Covid-19 were linked to an international flight into Ireland. Thirteen of the 49 passengers on board tested positive for Covid-19 and these passengers went on to infect another 46 people that they were in contact with.

The authors were unsure when the infected passengers became infected and acknowledge that this might have happened before the flight, during the flight, or during a connecting flight.

Regardless, this report offers a less reassuring take on the subject, stating, “this outbreak demonstrates the potential for spread of SARS-CoV-2 linked to air travel”.