Harvard Releases Study on Coronavirus Transmission Risk During Air Travel

October 27, 2020

This morning, Harvard released a report from the Aviation Public Health Initiative (APHI) to apprise the aviation industry and the traveling public about the risks of coronavirus (SARS-CoV-2) transmission during air travel. The focus of this 'gate-to-gate' report was to understand the dynamics introduced by the potential presence of SARS-CoV-2 in the confined space of a commercial passenger aircraft; and, to recommend actions and strategies to reduce and mitigate the risk of SARS-CoV-2 transmission on board the aircraft during flight as well as during boarding and deplaning. 

Based on independent and scientific analysis, the APHI study found that a layered approach of intervention in combination with face masks results in a very low risk of SARS-COV-2 disease transmission on aircraft. Specific findings of the layers studied include: 

  • Commercial passenger aircraft are equipped with a highly effective ventilation system that continuously circulates and refreshes the air supply, filtering out more than 99-percent of the particles that cause COVID-19, and rapidly dispersing exhaled air with displacement in the downward direction. This ventilation effectively counters the proximity travelers are subject to during flights. 

  • Universal wearing of facemasks by passengers and crew throughout the journey is critical because face masks significantly reduce the risk of disease transmission. 

  • Distancing protocols to manage the boarding and deplaning to maximize the distance as people move through the cabin are important. 

  • Cabin cleaning practices to disinfect and remove contaminants from high-touch aircraft surfaces that keep with EPA guidelines and cleaning recommendations from manufacturers are necessary.

  • Passengers and air crew should provide health attestations that they do not have COVID-19 related symptoms and have not been exposed to someone who is positive. They should also commit to adhere to airlines' mask policy.  However, the study does acknowledge that pre-symptomatic or asymptomatic people, who are contagious, could be unaware of their condition and continue to circulate in public. This is particularly true for flights originating from locations with a high incidence of cases. Until quick, inexpensive, and reliable airport testing is available, this presents a risk. Appropriate layers of protection - ventilation, face masks, and disinfection – counter this risk. 

  • Airlines and airports should continue their education and awareness campaigns to inform the public about actions they can take to reduce disease transmission on their journey. This includes public health safety information while booking, at check-in, boarding, and on the aircraft. Additionally, cabin crew should receive training to identify and isolate potentially infected individuals if a case appears on board an aircraft.

As additional research on the coronavirus and new technologies to mitigate risk emerge, APHI will monitor and report on these developments.

The Harvard team is now turning to a 'curb-to-curb' study on airport operations, which AAAE is supporting. They expect to release this report in approximately two months. 

For more details on the APHI work and links to review the documents can be found here: