SAN DIEGO (KGTV) – Millions of Americans will be flying this Memorial Day weekend and the chances of someone on your flight having COVID are higher than you probably think.
Based on testing data from UC San Francisco and the size of the aircraft, the odds could be greater than 99 percent.
This week, screening at UCSF found 6.2 percent of people entering its hospitals had asymptomatic infections, according to Department of Medicine chair Dr. Bob Wachter. That’s one in 16 people.
If that positivity rate is reflective of the general community, it would mean there is a 99.993 percent chance that at least one person has COVID on a plane carrying 150 people, Wachter noted.
More people might mask up if “the flight attendant showed a sign saying that at boarding,” he tweeted.
The positivity rate among students at UC San Diego was at 5.07 as of May 25. UCSD professor Dr. Robert Schooley said infection rates among students and hospital admits are likely higher than the population as a whole, but he noted there is a large amount of virus circulating in the community right now.
“We have as much virus in the wastewater in Point Loma as we did at the peak of the Delta epidemic,” Dr. Schooley said, adding that infections are resulting in less severe disease because of improvements in population immunity and changes in the variant.
On Thursday, the Centers for Disease Control and Prevention upgraded San Diego County’s transmission level from low to medium.
Commercial airplanes have advanced air filtration systems that make them less risky than some indoor environments. A modeling study published last year estimated that the average risk of infection on a two-hour flight with no masks was 2.5 percent.
If you sat next to an infected person, the risk rose to 60 percent.
However, that study was based on the infectivity of the original virus, not the ultra-transmissible Omicron variants that are dominant today.
Dr. Schooley said if he were traveling this weekend for Memorial Day, he would wear a mask both in the terminal and on the aircraft.
An ABC 10News reporter watched 100 passengers enter the security lines at San Diego International Airport’s Terminal One on Thursday afternoon. Just 17 people were wearing masks.