A Guelph vaccinated mother who, along with her partially vaccinated 15-year-old son, says they contracted COVID-19 in her family home wants people to know about the importance of good ventilation and communication in shared dwellings.
“I think just living in those two completely separate spaces, I just didn’t really ever consider how much her air was circulating through our house,” said Kirstin Galbraith.
Her son, Julian, suffers from seasonal allergies so the family had not considered he may be ill with COVID-19 when he came down with a runny nose and mild sore throat nearly two weeks ago.
Galbraith’s friend had access to a number of antigen tests at home so she decided to test Julian, just in case.
“I went and picked one up. We did it and it was positive. So I called her and said ‘it’s positive.’ And she’s like, ‘it must have been a bad one, let’s do another one,’ so I got another antigen test and positive! And that is when we said, ‘OK, this is something we should take seriously’ and the next day he and I went and had PCR tests done and got the results Sunday morning and he was positive,” she recalled.
Galbraith was shocked. As a teacher, she’d been working from home for months, while her two sons had been engaged in online learning.
“We’d been so careful and the whole world is opening up and so few cases right now and it just seemed implausible that this had happened,” she said.
“I have erred on the side of almost too cautious where we really have locked it down and we haven’t had a bubble, we haven’t been having people in our home or going into other people’s homes or anything like that.”
Galbraith immediately reached out to the basement tenant in her home to advise her that Julian was COVID positive.
“Texted her and said, ‘hey, so sorry, but here’s the deal’ and she said, ‘oh, I’m on day seven of COVID,'” she said.
Julian’s bedroom is above the tenant’s in the home. This proved to be the family’s only confirmed source of exposure to COVID-19.
“It came together like a puzzle in my head … his bedroom is two floors above, but it’s right above where she sleeps. He sleeps with his door closed. We had the air conditioning on, his window is closed. We had this little box that he was sleeping in with no airflow. And clearly it just traveled up through the vents and and that’s where he contracted it,” she explained.
Galbraith and her younger son were also tested. His test came back negative for COVID-19, but she tested positive. She has remained asymptomatic.
“You may think of yourself as living in a separate household, but if you’re sharing air, if you have someone living in the basement or you have somebody living above you, there is the risk of transmission,” said Infectious Disease Epidemiologist Ashleigh Tuite.
“If you are infected with COVID, even if somebody isn’t in your traditional definition of your household, if you’re sharing space and if you’re sharing air, you should be considering those people as your contacts and advise them of the fact that you’re infected,” she added.
Experts say keeping windows open could be key to minimizing the risk of transmission.
As a teacher, Galbraith was aware of the benefits of masking and keeping the door and windows open in the classroom, but it had not occurred to her that precautions were needed in her home.
“What ends up happening is that if you’re in a home and let’s say the air conditioning is on, say all the windows are closed, the fresh air delivery or the amount of dilution that’s going on is limited,” explained ventilation expert Duncan Phillips of engineering firm Rowan Williams Davies and Irwin.
“And these droplets, when it’s a drop, when you sneeze and it falls to the surface, it’s gone. But when it’s a small, fine droplet and it evaporates a little bit, it becomes an aerosol and starts to float around. The only way to get rid of that is dilution.”
Phillips noted heating, ventilation and air conditioning systems and their filters are designed to reduce airborne pollutants.
“You stick in this filter that’s got the MERV (minimum efficiency reporting value) 13 category and it basically knocks out 50 percent of any of those aerosol particles we’re worried about,” he said.
Galbraith’s son has recovered, but she wanted to share their story as Ontario gets set to enter Step 3, which will allow for indoor dining and movie theatres to reopen.
She also pointed out, her son’s symptoms were similar to those of seasonal allergies or a cold, and she had no symptoms at all, so had the family not been tested, the virus could have spread further.
“It would have been really easy to ignore the symptoms we had and to go and have dinner in a restaurant where who knows what the ventilation is like, now that I know how easily it can spread just through ventilation,” she said.
Tuite noted this is a good example of why it is always best to get tested, even if you’ve been vaccinated.
“I think that’s something that we need to be mindful of as we move into this era where we have a lot of people who are fully vaccinated, which is not to be dismissive of symptoms that you do have because they could be COVID and so if you have the symptoms … if you have any reason to think that you might be infected, you should get tested.”