Heavier breathing, spitting droplets, poor ventilation add to the risk of excessive room spread

0
8


A recent outbreak of COVID-19 at a southern Ontario fitness studio illustrates how certain indoor environments can provide a perfect storm for mass-market events.The studio, a downtown Hamilton Spinco location, was connected to 69 cases of COVID-19 on Wednesday, despite screening customers, operating at 50% capacity and keeping the recommended two-meter radius around bikes.

So how did so many cases come into being there? And does that raise concerns about how the new coronavirus may be spread in a gym?

“Certainly this event makes you wonder that,” said Dr. Matthew Oughton, an infectious disease expert at the Jewish General Hospital and McGill University in Montreal.

“I can see where this could possibly lead gyms to have serious restrictions placed on them if they are to avoid similar mass-market events. ”

Ontario and Quebec recently reintroduced gym closures in virus hotspots, including Toronto, Montreal and Ottawa, for a period of four weeks to limit the spread.

And Dr.Barbara Yaffe, Ontario’s deputy chief medical officer, said on Wednesday authorities were reviewing guidelines for the province’s fitness studios after the Hamilton outbreak.

Oughton said gyms and fitness studios have a few strikes against them when it comes to adapting them to the pandemic.

Heavier breathing expels droplets further

They work almost exclusively indoors, which reduces ventilation, and clients are generally not masked when they exercise intensely.

High-impact activity also leads to heavier breathing, which means droplets are being pushed out of people’s mouths at an accelerated rate – and are propelled further.

A gymnasium worker in Gatineau, Que., Wipes down equipment in late June during the pandemic. When people exercise vigorously, the volume and distance of what comes out of their mouths and lungs differ from those who speak normally. (Frédéric Pepin / Radio-Canada)

Dr. Andrew Morris, professor of medicine at the University of Toronto, likens it to throwing a ball. The harder you throw, the farther it goes.

“We still don’t have a perfect understanding of this,” he said. “But we know that when people exercise vigorously, the volume and distance of what comes out of their mouths and lungs are drastically different from those who speak. [in a normal way]. «

WATCH | Dr. Theresa Tam, Canada’s Top Physician, on Aerosol Transmission:

Chief Public Health Officer Dr. Theresa Tam admits guidelines for COVID-19 transmission may need to change. 1:00

If people shout, cheer, or sing – which often happens in a pirouette class where the music blasts and the instructors spit out encouragement to keep the participants up – it can make matters worse.

“And if you mix that up with a space that maybe doesn’t have adequate ventilation, there’s a risk that a lot of spread will happen,” Morris said.

Dr. Ilan Schwartz, an infectious disease specialist at the University of Alberta, said spinning classes may pose more risk than other groups because of the bikes themselves. In theory, the wheels that spin quickly could aerosolize the droplets by throwing them farther.

“I haven’t seen any studies on this, but theoretically it makes sense,” he said.

“I think going to the gym is not necessarily high risk, unless people are close to each other and there is poor ventilation. But there may be specific circumstances that could increase the risk, where something with fast moving parts [or] a fast moving fan can also generate aerosols. ”

Holland Philpott is participating in an outdoor dome yoga class to facilitate distance and proper protocols to prevent the spread of COVID-19, in Toronto in June. (Carlos Osorio / Reuters)

But Morris said the real danger arises when people spit droplets into a poorly ventilated space.

The dangers of fitness classes are not equal

The extended time spent in a spin class, usually an hour, and the number of people in the room will also impact the risk.

Not all fitness classes will present the same dangers, he added.

A low impact yoga class where hearts aren’t beating and breathing is controlled seems safer than a high-impact spin class, but not if it’s crowded and poorly ventilated.

A dance class, where participants roam through airspace previously occupied by others, can also be risky in the same environment.

A lone jogger, wearing a protective mask, runs with her dog in the Tuileries garden in Paris as a lockout is imposed in March. Masks, although uncomfortable during training, can be worn. (Charles Platiau / Reuters)

“Assuming this room has relatively low ventilation, this is the kind of setting where yes, you would be concerned about transmission potential,” Oughton said. “But if you had the exact same room with a great HVAC system, or the same room where the windows were kept open… these are the kinds of things you could do to reduce risk.

Morris said it was always better to find ways to make these activities safer than to ban them.

The masks, while uncomfortable during training, can be worn in most cases, he said. Improving ventilation and limiting the number of people even further can also help.

“If we’re going to be successful, we can’t keep telling people they can’t have these things,” Morris said. “We have to be able to point the finger at something and say, ‘This is the best choice’.

Schwartz said frequent hand cleaning and disinfection of equipment should also be kept in mind, although surface transmission is not as much of a concern as at the start of the pandemic.

“And for now, I think it’s probably a good idea to avoid spin classes,” he added.

Oughton predicts that people will take their workouts outdoors in new ways during the winter if gyms and fitness centers are deemed too risky.

This could mean dusting off skates or ski boots.

“I think this will again underline safety and the need to be able to have activity and fresh air outside,” he said.

“Hopefully we find a new appreciation for outdoor winter sports that we can all enjoy. “

LEAVE A REPLY

Please enter your comment!
Please enter your name here