Is it safe to swim in a pool during the COVID-19 pandemic?
TORONTO -- As temperatures across Canada continue to rise, few things do a better job of keeping us cool than going for a swim.
But with the closure of public swimming pools across the country due to the COVID-19 pandemic, many may be left wondering how safe it will be to return to these spaces once they reopen.
According to Matthew Miller, a biochemistry professor at McMaster University in Hamilton who is studying the novel coronavirus, COVID-19 is highly unlikely to be transmitted through water.
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“Respiratory viruses like COVID-19 are different from viruses like polio or other pathogens like cholera that are actually spread in water,” he told CTVNews.ca over the phone on Monday. “The risk of contracting the virus from the pool water itself is likely very low.”
While no major studies have been conducted on the lifespan of COVID-19 in water, the U.S. Centers for Disease Control and Prevention (CDC) have said “[t]here is no evidence that the virus that causes COVID-19 can be spread to people through the water in pools, hot tubs, or water playgrounds.”
Community pools remain closed across most of the country, though there are some exceptions. As of June 8, the Quebec government has authorized the reopening of outdoor public and private swimming pools as well as the sanitary portions of these facilities. Splash pads have also been given the green light to reopen.
Indoor and outdoor pools are currently open in New Brunswick, but residents must adhere to gathering limits of 50 people. Outdoor pools in Newfoundland and Labrador are open as well, but no more than 20 people are allowed in the pool and deck areas at a time. All pools in Prince Edward Island are also open, but face no restrictions on the number of people allowed.
Miller explained that exposure to water would weaken the virus, reducing its ability to cause infection.
“Any virus that’s in water would be super diluted, so you likely wouldn’t be exposed to any appreciable concentration of it,” he said.
Infectious disease specialist Dr. Neil Rau also explained that the chlorine normally found in public pools would serve to kill the virus. This means that the risk of contracting COVID-19 from swallowing water, for example, is very slim, he said.
“Chlorinated water in a classic swimming pool would have an antiviral effect,” he told CTVNews.ca via telephone on Monday. “You don’t get this virus through consumption or aspiration of water.”
The CDC share a similar view, stating that “proper operation of these aquatic venues and disinfection of the water (with chlorine or bromine) should inactivate the virus.”
WHERE DOES THE RISK STEM FROM?
The risk of contracting COVID-19 somewhere like a public pool isn’t so much in exposure to the water, but rather to “people crowding together in an enclosed space,” Dr. Isaac Bogoch, an infectious disease specialist with the University Health Network in Toronto, told CTVNews.ca on Monday.
According to the World Health Organization (WHO), COVID-19 is mainly transmitted from person to person through respiratory droplets released from the mouth or nose. The infection spreads when a person with the virus coughs, sneezes, or exhales, and someone else breathes in these droplets.
While it is also possible to contract COVID-19 from touching a surface contaminated with the virus, and then touching their eyes, nose or mouth, this isn’t believed to be the main source of transmission, according to the CDC.
This is why government and health officials across the country continue to recommend maintaining a physical distance of at least two metres from those around you. Rau explained that while this is imperative in preventing the spread of COVID-19, it can likely be difficult to do at public pools, especially in communal areas such as change or locker rooms.
Being in such close proximity to other people can place someone at greater risk of contracting or transmitting COVID-19. For this reason, it’s advised to try your best to stay at a distance, said Rau. The doctor also predicts that pools will have to limit the number of people they allow in at a time.
“I could see staggered swim times being an option if you want to completely minimize risk,” he said. “It’s a form of physical distancing – you’re segmenting them from a group that might bring them the virus.”
Physical distancing continues to be a concern while swimming in pools at a friend or family member’s house, explained Miller. In addition to following provincial guidelines on the size of gatherings, he recommends maintaining physical distancing guidelines inside the pool as best you can. This means only allowing enough people in so that they can be spaced out appropriately.
Bogoch also points out that high-contact surfaces such as door handles and handrails in public spaces can also be a potential source of transmission for COVID-19.
To combat this, he suggests adhering to national guidelines on cleaning and disinfecting public spaces, as well as diligent hand hygiene. This means washing your hands with soap and water for at least 20 seconds or using an alcohol-based hand rub with more than 60 per cent ethanol and 70 per cent isopropanol.
“The devil's in the details,” he said. “If those measures are adhered to, I think the risk [of contracting COVID-19] would be quite low.”
The limited circulation of air typically found among indoor swimming pools can also lead to an increased risk of transmitting COVID-19.
According to Rau, respiratory droplets carrying COVID-19 are more easily spread in confined spaces, especially ones that are not properly ventilated.
“Almost all of the big [COVID-19] outbreaks that we know about are indoor outbreaks where ventilation is poor,” he explained. “Or where it’s a shared air space without the continuous air exchanges you get when you’re outdoors due to prevailing winds or the amount of air that’s recirculating.”
For this reason, Miller advises sticking as much as possible to outdoor swimming pools rather than indoor ones. Another option to consider would be a beach or lake, depending on whether they’re open.
Not only is air ventilation no longer an issue, but the greater amount of space makes it easier to adhere to physical distancing measures.
“The real risk of transmission comes from other people and not from the water,” said Miller. “It’s important to be really thoughtful about that spacing.”
STEPS YOU CAN TAKE TO MITIGATE RISK
Aside from guidelines already recommended by government and health officials, Miller suggests preventing any water in the pool from entering your mouth.
“People should be conscious about … dispersing water in the air from their mouths,” he said.
For those considering wearing masks, Rau insists that unless you’re going for a stroll or simply sitting poolside, it isn’t feasible to wear one while swimming.
But the best advice, according to all three experts, is to maintain that physical distance and keep clean. Miller goes as far as suggesting taking a shower both before and after swimming of any kind, and making sure to scrub your hands while doing so.
“Maintaining regular handwashing is a good idea generally, but certainly more imperative in community pools or even backyard pools,” he said. “Just do all the same things that you would try and do normally.”
An earlier version of this story incorrectly said that indoor pools were also open in Newfoundland and Labrador.