CDC study: Leaving middle seat open on planes could reduce COVID-19 exposure

A Centers for Disease Control and Prevention (CDC) study found leaving the middle seat vacant on planes could reduce COVID-19 exposure for passengers, supporting a practice that has now been abandoned by most airlines. 

The research released on Wednesday predicted that keeping the middle seat empty on flights could reduce the risk of exposure by 23 percent to 57 percent depending on the seating occupancy model. 

The study, conducted in part with Kansas State University, used the bacteriophage MS2 virus to stand in for the COVID-19 virus to study how the seating arrangements could affect passengers’ exposure to the virus. 

The highest reduction of exposure, at 57 percent, was observed when studying three rows of passengers with and without passengers in the middle of three seats.

The researchers found a 35 percent to 39.4 percent reduction in exposure when removing middle seat passengers while examining how up to three infected passengers would affect a full 120-seat cabin. 

Another model estimated a 23 percent reduction in exposure when scientists moved a passenger one seat away out of the middle seat directly next to the infected passenger. 

“These data suggest that increasing physical distance between passengers and lowering passenger density could help reduce potential COVID-19 exposures during air travel,” the study reads. “Physical distancing of airplane passengers, including through policies such as middle seat vacancy, could provide additional reductions in SARS-CoV-2 exposure risk.”

The study did not examine how masks could affect the COVID-19 exposure in different seating arrangements because the original portion of the study at Kansas State University was conducted in 2017, before the coronavirus pandemic. 

Researchers highlighted that the study only measures COVID-19 exposure and not necessarily transmission to other passengers. 

Earlier in the pandemic, airlines blocked passengers from booking middle seats as they pushed to resume service while easing worries about contracting COVID-19. But most airlines have slowly begun allowing full capacity on planes, with mask requirements.

Delta Air Lines is the last U.S. airline with a ban on passengers sitting in middle seats on flights, but the company announced the restriction would end on May 1. The airline did unblock middle seats for two days this month amid a series of about 100 canceled flights. 

The CDC issued an order in January mandating all passengers older than 2 years old wear masks on public transportation, including airplanes. The federal agency has also recommended that only people who are fully vaccinated against COVID-19 should travel.