Airborne transmission, back-to-school and more: Experts answer your COVID-19 questions

Checkup callers responded en masse last week for our Ask Me Anything segment about COVID-19 masks and face coverings.

As the pandemic continues, questions have persisted and evolved, as Canadians mull their approaches to summer activities and plans for returning to school.

Dr. Susy Hota, director at the University Health Network in Toronto, and Dr. Srinivas Murthy, a pediatric critical care and infectious diseases specialist in Vancouver, have reconvened the COVID-19 AMA panel.

Here are some of their responses for listeners and guest host Rosemary Barton.

Is it safe to go back to school?

After months of at-home schooling and taking courses online, a limited number of students returned to class part-time in June.

Tamara Maxim of Burnaby, B.C., is a school teacher herself and had a lot of questions about what classrooms will look like this September.

"I was in schools. I was with kids. I've seen how it went. I experienced a lot of discomfort but being mandated to do what I needed to do by my school district," she said.

According to Murthy, who is a parent and a pediatrician, every region's community-level spread will help determine when or whether it will be safe to go back to five-day classes at full capacity for students and staff.

Even if a region sees "a reasonably flat curve," he said there will be many things to decide, including how far students will need to sit apart, how to protect adult staff who are immuno-compromised and whether further accommodations may require major renovations on school grounds.

"Fundamentally, I think it's a priority to get kids back in school … from the parents' perspective and their perspective. We just need to make sure all of those things are lined up as much as possible," he said.

Should I be worried about surface transmission?

Robert Brewster from Vancouver Island asked about concerns about surface transmission — specifically, whether liquor stores are justified in limiting or cancelling their empty bottle return policies.

Many Canadians have furiously wiped down and sanitized high-traffic surfaces at their homes like doorknobs and even packaged goods in their grocery hauls amid fears that the coronavirus may survive in a transmissible state on various surfaces.

But on Thursday, the World Health Organization said there have been "no specific reports" of COVID-19 directly from contact with contaminated surfaces.

"I think the risk of recycling, specifically, is incredibly low from you to your recycler," said Murthy.

Should I be worried about airborne transmission?

Loretta Amundsen from Georgina, Ont., is one of many Canadians with questions about whether COVID-19 can spread via airborne transmission.

She expressed worries about having friends over to her house, which has a lakeside dock and deck if the breeze from the swift water current might also be carrying the virus.

More than 230 scientists signed an open letter in early July calling on WHO to declare the virus can be spread through the air. The UN agency has resisted this, saying that while there is some evidence emerging, none of it is definitive.

Hota said that as it's currently understood, transmission via smaller droplets known as aerosols "are not the main driver" of infections. Further, she said that if some of the fears about airborne transmission were founded, indoor infection rates in particular would likely be much higher than they currently are.

She added that as long as everyone maintains physical distance guidelines outside, the flurry of air currents should protect them against infection rather than present a threat.

How strict is my social bubble?

As municipalities gradually reopen their economies, Bernice Chaplin of Toronto wondered how difficult it will be to maintain their social bubbles.

"Some of use are going to daycare or getting a haircut, et cetera. I'm just wondering if you can be in the bubble if you are doing those things," she said.

Hota advised people to be as aware of what others in their social bubble may be doing as possible and inform others of what they are doing themselves in return.

Hota added that as reports of community transmission goes down, people may begin to think about slowly increasing the size of their bubbles.

"I think it's more about how responsibly people are behaving, right. You have to be able to trust those in your bubble that they're doing what they need to be doing," she said.

How to keep safe in public washrooms?

Dr. Bruce Aylward, who led WHO's COVID-19 mission in China, expressed concerns about using a public washroom on Checkup back in March.

Checkup listener Barbara Finlayson was similarly concerned about possible hot spots, especially high-powered hand blow dryers and toilets without seat covers.

"It's a tough question," said Hota. "You don't really know who's been in there or what the situation is."

She recommended following the usual protective measures, such as thorough handwashing and avoiding contact with as many surfaces as possible.

She advised paper towels for hand-drying over blow dryers. 

"If you happen to be in a washroom with one of those old-school towel-pull type dryers, I would avoid that by all means," she added.

Written by Jonathan Ore with files from Kirthana Sasitharan and Shahroze Rauf.