Does sanitizing the NYC subway help kill COVID-19? Experts weigh in

Wearing a face mask “will protect us the most," one professor said

New York City shut down its subways overnight and tested powerful ultraviolet lamps to disinfect seats, poles and floors to curb the spread of the coronavirus. Now experts are weighing in if these unprecedented — and expensive — steps are beneficial in slowing the virus’ surge.

The cleaning measures produced something commuters have not seen in a while, or possibly ever: thousands of freshly scrubbed cars that look, feel and even smell clean.

All that cleaning does cut the threat of catching the virus, experts say, but the benefits are limited.

The virus transmits predominantly through droplets in the air — it’s “everywhere and could be nowhere,” Robyn Gershon, a clinical professor of epidemiology at New York University, told The Associated Press.

Cleaning a train car at a maintenance yard overnight — or even several times during the day, as New York’s Metropolitan Transportation Authority does — might not help the transit employee or passenger stuck in close quarters with a coughing person.


Wearing a face mask “will protect us the most, having that control among ourselves,” Gershon said. “I think the rest of it is really more the illusion, and that’s not a small thing because it plays with our psyches.”

Patrick Warren, the MTA’s chief safety officer, said the authority’s aggressive cleaning and disinfecting began at a time when health officials were warning that the virus could easily be transmitted from hard surfaces — guidance that has since evolved to place more emphasis on airborne transmission.

“As goes the science, so goes what we are doing,” Warren said.

New York’s subway system normally serves more than 5 million riders a day, but ridership plunged more than 90 percent at the height of the pandemic. Combined with plummeting revenues at its toll bridges and tunnels, the MTA has projected the pandemic will cost the agency more than $10 billion through next year. The cleaning program will likely cost hundreds of millions of dollars, officials said in the spring.

Is it worth the price? A survey of 1,000 mass transit riders conducted by New York-based advocacy group Tri-State Transportation Campaign found that cleaning topped a list of actions people wanted before they would feel comfortable riding mass transit again.

“But to what extent are we now overspending, or veering too far into security theater?” Executive Director Nick Sifuentes asked recently.

Dr. David Brenner, director of the Center for Radiological Research at Columbia University Irving Medical Center, has assisted the MTA on its UV light pilot program. He called the cleaning “not an ideal solution, but it’s a solution that is available.”

“I think it does increase the public safety because instead of having a continuous buildup of the virus, you are going back to zero every day,” Brenner explained to the AP. “A much better solution would be if you could continuously decontaminate the air throughout the course of the day.”

That remains a possibility. Two studies, one from 2018 and one from this month, concluded that low levels of a certain type of ultraviolet light, known as far-UVC light, can be circulated continuously in an enclosed space and kill some forms of human coronavirus as effectively as conventional UV light.

Far-UVC light could offer a whole new level of protection for passengers and transit employees, if it is also found to be effective against the virus that causes COVID-19.

The MTA is already testing a different form of UV light to disinfect subway cars, but it can only be done at station yards when the cars are out of service because of the harmful effect on humans. The limited pilot program costs about $1 million.


The Associated Press contributed to this report.