"We were already extremely nervous about the prospects of flying," said Dr. Akshar Rambachan, an academic hospitalist with UCSF.
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Rambachan and his wife suited up in ponchos and masks before boarding their Sun Country Airlines flight from SFO to Minneapolis on July 2.
The company has a strict mask policy posted on their website that applies to all employees and passengers.
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"People were boarding the plane without wearing masks," he said. "There was an overhead announcement to wear masks, but there was no enforcement."
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The couple was seated towards the back of the packed plane. Rambachan said most three passenger rows were full and roughly a dozen people were not masked.
"It was extremely uncomfortable," he said. "The idea of getting on a plane and visiting our elderly parents, despite all we did to be sanitized, maybe we weren't going to come out safe."
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The World Health Organization hasn't ruled out airborne transmission of the virus in crowded, indoor spaces with poor ventilation.
"But, it seems to me to be rare," said UCSF lead epidemiologist Dr. George Rutherford.
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"In certain situations, there may be enough of the fine particles containing the virus that can hang in the air long enough so people can become infected."
While it may be rare, Dr. Rutherford still said airborne transmission is possible.
"People have to wear masks on flights... that's unforgivable."
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ABC7 News reached out to Sun Country Airlines for a comment and was provided the following statement:
As always, Sun Country is committed to the safety of our passengers and crew. We are taking additional steps and have instituted new policies in an effort to mitigate risk to travelers due to COVID-19. We require masks be worn by airport staff, crews and passengers. We will not allow any passenger to board without a face covering, unless exempt due to medical condition, such as requiring the use of an oxygen mask. We have seen some reports of noncompliance. When we get these reports our operational leadership team investigates the events and evaluates how we can better communicate with passengers and crews to ensure compliance on future flights.
Meanwhile, masks are required at SFO where at least four TSA employees have tested positive for COVID-19. One of those employees was working up until June 24, according to the agency's website.
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"We are working on a reduced need for anyone to have to touch anything throughout the process from checking in, getting a boarding pass, and checking a bag," said Doug Yakel, on behalf of the airport.
Yakel said there are a dozen airport ambassadors enforcing the mask mandate throughout the terminals.
"We are there to educate those you may not know and are hoping for voluntary compliance," Yakel said.
No fines will be issued.
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