AIR, ASTHMA, AND EQUITY: WHAT SHAPES KIDS’ LUNG HEALTH TODAY

Dr. Teresa To has spent her career changing how we understand and respond to asthma. As a senior scientist at the Hospital for Sick Children and Professor at the University of Toronto’s Dalla Lana School of Public Health, she’s recognized as one of the first researchers in Canada to use population-level data to study asthma. That work has helped define the burden of asthma across the country, laying the foundation for targeted care and better outcomes.

Born and raised in Hong Kong, Dr. To moved to Canada in her early twenties and now calls Toronto home. She’s been academically focused her entire life, going straight from kindergarten to a PhD. But her focus sharpened after a conversation with her father, when she realized she lacked the hands-on skills to help others in the way she wanted. That moment pushed her to keep learning—and ultimately led her to asthma research.

When Dr. To first joined SickKids, she was asked to assess how common asthma was in Ontario. What seemed like a simple data task turned into a turning point. “I thought I’d just be counting cases,” she recalls. “But asthma was the number one reason kids were admitted to the hospital. That shocked me. I realized this wasn’t a minor condition.” From that moment on, she committed her research career to asthma.

Today, Dr. To holds a Tier-1 Canada Research Chair in asthma and represents Canada on the WHO’s Global Alliance Against Respiratory Diseases. She also leads the Ontario Asthma Surveillance Information System (OASIS), which uses large-scale data to track asthma trends across the province. OASIS reports are cited both nationally and internationally, helping to inform decisions around care and policy. In Ontario alone, about 30,000 to 50,000 people are newly diagnosed with asthma each year—and over 30,000 visit the emergency department annually because of it.

Over the years, Dr. To’s work has expanded into how environmental factors impact asthma. As the research lead for the Environmental Health Platform of the Canadian Respiratory Research Network, she’s looked closely at how air pollution increases the risk of asthma attacks—and even speeds up the progression to COPD. Her landmark study in the American Journal of Respiratory and Critical Care Medicine showed that high exposure to pollution can more than double the risk of an asthma attack. “Some people say, ‘Toronto air isn’t that bad,’” she explains, “but seasonal fluctuations and wildfire smoke still make it a major concern.”

More recently, she’s turned her attention to youth vaping and cannabis use—two rising threats to respiratory health. She encourages doctors, especially pediatricians, to ask young patients about their use. “Kids as young as nine are vaping, and many doctors don’t even think to ask. But the impacts can last a lifetime,” she warns.

Dr. To also leads research into access to biologics for asthma, with strong support from Asthma Canada. “They funded a third of our study looking at how biologics are used in real-world care—who benefits, who’s left out, and whether they’re cost-effective,” she says. She credits Asthma Canada, and particularly Jeff Beach, for helping make the project happen. “We can’t do this work in isolation. Partnerships like this are essential.”

Despite her many accomplishments, Dr. To remains humble about her contributions. “I haven’t discovered a gene or cured a disease. But I’ve added pieces to the puzzle—pieces that help us better understand asthma’s real-world impact.” She remains concerned that asthma research often falls behind in funding. “There’s so much attention on cancer and heart disease, but asthma still affects millions of people. We haven’t solved it yet.”

To early-career researchers, she offers encouragement—and a call to action. “Asthma research is still full of potential, but it needs more support. If we invest in it, we can make a real difference for the next generation.”