On the 2-Row Rule for Infectious Disease Transmission on Aircraft

Area of Science:

• Epidemiology
• Public Health
• Aviation Safety

Background:

• In-flight transmission of infectious diseases is a significant global health concern due to over two billion annual airline passengers.
• Existing public health guidance suggests the primary transmission risk for respiratory infectious diseases is within two rows of an infected passenger.
• The precise influence of various factors on in-flight transmission, including passenger proximity, remains unquantified.

Purpose of the Study:

• To evaluate the actual risk of infection for passengers seated within and beyond the established two-row proximity rule.
• To provide a data-driven assessment of transmission risks in air travel.

Main Methods:

• Literature review of documented in-flight transmission of infections.
• Analysis of available seat maps to identify the seating arrangements of infectious and infected individuals.
• Quantitative assessment of transmission risk based on passenger proximity.

Main Results:

• Passengers seated within two rows of an infectious individual have approximately a 6% risk of infection.
• Passengers seated beyond two rows from the infectious individual still carry a notable risk of approximately 2%.

Conclusions:

• Contact tracing limited to the two-row rule may miss a significant proportion of infection cases.
• Infections occurring at greater distances suggest that factors such as cabin airflow, passenger/crew movement, fomites, and pre- or post-flight interactions play a crucial role in disease transmission.
• A broader approach is needed to assess and mitigate in-flight infectious disease spread.