An Overview of Federal Law Governing the Carriage of Passengers Who May Have a Communicable Disease on International Flights

On March 11, 2020, the World Health Organization designated the outbreak of COVID-19, also known as Coronavirus, as a pandemic.  As communities implement measures to prevent the spread of the virus, air carriers seek to identify the measures they are permitted to take in the event a passenger suspected of having the virus attempts to board a flight, as well as the potential for liability following transmission of the virus during flight.

The following is a discussion of federal regulations addressing an air carriers’ authority to screen passengers with communicable diseases and deny transportation, and the liability scheme governing personal injury claims in international transportation.

Federal Regulations

The U.S. Department of Transportation (DOT) maintains a comprehensive regulatory scheme to implement the Air Carrier Access Act (ACAA), a federal statute which prohibits discrimination in air travel on the basis of disability.  Also known as “Part 382,” the goal of these regulations is to ensure that individuals with physical or mental disabilities have equal access to air transportation, while accounting for practical and operational limitations encountered by air carriers.

The Federal Regulatory Scheme Governing Air Carriers’ Ability to Refuse Transportation to a Passenger Who Has a Communicable Disease

Air carriers are not permitted to limit a passenger’s access to transportation on the basis that they have a communicable disease – either by refusing to transport the passenger, imposing on the passenger a condition not imposed on others, or requiring that the passenger provide a medical certificate – unless the passenger poses a “direct threat” to the health or safety of other passengers.1  A communicable disease poses a direct threat if it: 1) can be readily transmitted by casual contact in the aircraft cabin; and 2) represents a significant health risk.2  (The DOT has identified SARS (Severe Acute Respiratory Syndrome) as one such example.)  In making this assessment, carriers may rely on a directive issued by public health authorities such as the U.S. Centers for Disease Control or World Health Organization.3

In the event a passenger has a communicable disease that constitutes a “direct threat,” a passenger may present to the carrier a medical certificate describing the measures for preventing transmission of the disease during the normal course of flight.  In such a case, the carrier must accept the certificate and provide transportation unless it is unable to carry out the measures described in the certificate.4  An exception to this rule is where the carrier legitimately believes that the certificate significantly understates the passenger’s risk or that there have been significant adverse changes in the passenger’s medical condition in the time since the certificate was issued.  In that case, the carrier may require that the passenger undergo additional medical review to ascertain whether the passenger would pose a direct threat or would be unlikely to complete the flight without requiring extraordinary medical assistance; if so, the carrier can deny boarding.5

If the carrier’s actions result in the postponement of the passenger’s travel, the carrier must permit the passenger to travel up to 90 days from the date of the originally scheduled travel and must honor the original fare without penalty, or provide a refund for any unused flights, at the passenger’s option, and also must provide a written explanation (upon request) of the reason the travel was restricted within 10 days.6

In addition to defining air carriers’ regulatory liability, Part 382 and the Federal Aviation Regulations also likely define the standard of care applicable to claims by passengers arising out of the spread of COVID-19.

The DOT Has Issued An Enforcement Notice Regarding Screening of Passengers on International Flights for COVID-19

On March 2, 2020, the DOT issued an Enforcement Notice to advise the public and air carriers of certain measures which carriers will be permitted to undertake to screen passengers during check-in and boarding for symptoms of COVID-19.7  The Enforcement Notice pertains only to flights to the U.S. from countries with travel health notices issued by the CDC stemming from the COVID-19 pandemic.

In the Enforcement Notice, the DOT expressly authorizes air carriers to directly screen passengers for symptoms of COVID-19 prior to traveling on affected flights.  If a passenger has a fever or reports having a fever, or if a passenger exhibits shortness of breath, the DOT’s Enforcement Office will not enforce the requirement that carriers first ask for a medical certificate before denying boarding to the passenger.  The DOT noted that the potential for COVID-19 to spread rapidly and cause severe health consequences “highlights the fact that obtaining a medical certificate would likely not be sufficient to demonstrate that a passenger is not a direct threat to the health or safety of others.”

Notably, the DOT reaffirmed the existing regulation that requires carriers to permit passengers to travel at a later time or receive a refund if they are not permitted to board due to suspicions of COVID-19, and further reminds carriers that they must provide a written explanation of the reason the travel was restricted.

The Montreal Convention Governs Claims Arising from Transmission of Communicable Disease During an International Flight

An air carrier’s liability for personal injuries arising from the spread of COVID-19 during international travel is likely to be very fact-intensive.  No court has directly addressed the issue under Article 17 of the Montreal Convention; thus, the analysis for determining liability is the same Article 17 “accident” analysis pursuant to which an air carrier is liable for an “unusual or unexpected event or happening that is external to the passenger” that is not “the passenger’s own internal reaction to the usual, normal and expected operation of the aircraft.”8

An air carrier should not be liable to a passenger who contracts a communicable disease if the point of contracting such disease occurred prior to boarding the aircraft since courts have consistently held that complications arising from a passenger’s pre-existing medical condition are not unusual or unexpected events or happenings external to the passenger, and so are not “accidents” under the Montreal Convention.  In contrast, where the point of contraction occurs on board the aircraft, an air carrier’s liability would likely depend on whether “contraction” is an “event or happening.”  Contracting a communicable disease on board an aircraft is undoubtedly “unusual and unexpected” and “external to the passenger,” but whether “contraction” is an “event or happening” is unclear.

It is likely, however, that an air carrier would be liable if a passenger contracts a communicable disease on board an aircraft as a result of some action or inaction by the crew, including refusal to accommodate a passenger’s specific request to be moved away from another passenger demonstrating symptoms. Courts have held that an air carrier’s response to a passenger’s medical condition is external to the passenger, and may constitute an event or happening for purposes of establishing liability.  In similar fashion, an air carrier may be liable if a passenger contracts a communicable disease on board the aircraft as a result of the air carrier’s failure to comply with industry standards and/or airline policy.  Accordingly, air carriers should ensure compliance with international, federal and state regulations and guidelines concerning infectious diseases, such as Part 382 and the Enforcement Notice, which may be deemed “industry standards.”9

To be clear, an air carrier’s failure to adhere to these regulations and guidelines could be a factor when determining the air carrier’s potential liability.  A violation is not per se an “accident;” rather, the departure must be unusual or unexpected.  Likewise, compliance with these regulations and guidelines is not automatically a defense to liability under the Montreal Convention.

While the nature and extent of liability to passengers in these uncertain times of COVID-19 is unknown, the DOT is attempting to balance passengers’ rights to access air travel against the industry’s responsibility to protect the travelling public from risks inherent in air transportation.  Accordingly, airlines should take their cues from the DOT and governmental health organizations for the time being.

Disclaimer: This publication is made available for educational purposes only and is not intended as legal advice. If you have questions about any matters in this publication, please contact the authors directly.  General inquiries may be directed to

1 14 C.F.R. § 382.21(a).

2 14 C.F.R. § 382.21(b)(2).

3 14 C.F.R. § 382.21(b)(1).

4 14 C.F.R. §§ 382.21(c); 382.23(c).

5 14 C.F.R. § 382.23(d).

6 14 C.F.R. § 382.21(d)-(e).

7 Enforcement Notice Regarding Denying Boarding by Airlines of Individuals Suspected of Having Coronavirus, Mar. 2, 2020,

8 Air France v. Saks, 470 U.S. 392, 405-06 (1985).

9 See, e.g., Olympic Airways v. Husain, 540 U.S. 644, 656 (2004).