March 02, 2026
For most families, asthma feels like it comes out of nowhere. A child starts coughing or wheezing, and suddenly there are inhalers, doctor visits and long-term questions. Treatments can help manage symptoms, but there is no cure. For years, preventing asthma has been far more difficult than treating it.
Asthma is the most common chronic disease of childhood. In Canada, about one in seven children lives with it. It is one of the main reasons kids are admitted to the hospital and miss school. Asthma costs the healthcare system more than $2 billion every year.
Research supported by Genome BC and Genome Canada has reshaped our understanding of when asthma truly begins.
Looking for answers before symptoms start
Instead of studying asthma only after children get sick, Dr. Stuart Turvey and his team at the University of British Columbia took a different approach. Working with researchers from the Canadian Healthy Infant Longitudinal Development, or “CHILD” Study, they asked a simple but powerful question.
What if asthma risk starts much earlier than we thought?
To find out, they looked at babies in their first months of life, long before any signs of asthma appeared. They focused on a source of information that most parents know well: dirty diapers.
By analyzing infant stool samples using advanced genomics technologies, the researchers studied the bacteria living in babies’ guts and tracked how those early microbial communities developed over time.
What they discovered was striking. Differences in gut bacteria could be seen very early in life, and those differences were associated with a higher risk of developing asthma years later.
Why the first months matter
A baby’s immune system is still learning how to respond to the world. During those early months gut bacteria play an important role in shaping that learning process.
The research showed that breastfeeding helps support the growth of beneficial gut bacteria, while antibiotics, though often necessary, can disrupt those early microbial communities. These disruptions do not automatically lead to asthma, but they can influence how the immune system develops and how asthma risk unfolds over time.
B. infantis: here yesterday, gone today
One finding stood out. The researchers observed a sharp decline in Bifidobacterium infantis (B. infantis), a bacterium once common in the guts of breastfed infants and important in early immune development. Today, B. infantis is rare among infants in Canada and other industrialized countries.
This matters because B. infantis is especially well suited to digesting the complex sugars found in human breast milk. Breastfeeding helps support the presence of this bacterium during the first months of life, a critical period of immune development that helps shape a healthy gut environment. When B. infantis is missing, other bacteria can fill that space, but they may not provide the same immune benefits.
In other words, asthma does not suddenly appear when symptoms start. For some children, the groundwork may be laid much earlier during a brief and important window in infancy.
What this means for families and health systems
While asthma risk is shaped by many factors, the findings reinforce the importance of breastfeeding for child health, including its role in supporting a culture of beneficial gut bacteria during early immune development. Understanding how these early influences shape risk can help families make informed choices, without blame or unrealistic expectations.
For healthcare systems and policy makers, the findings point to something equally important.
If asthma risk begins early, prevention needs to start early, too.
Decisions about infant care, antibiotic use and support for families do not just matter in the short term. They can influence long-term health.
This kind of insight is only possible through long-term research like the CHILD Study, which follows thousands of Canadian families over many years. The findings from this work are already informing healthcare policy discussions and laying the foundation for future approaches, such as earlier risk identification and microbiome-based prevention strategies.
Just as importantly, the project has led to international collaborations, high impact scientific publications and national recognition for Canadian researchers, strengthening Canada’s role as a leader in childhood health research.
A healthier start for Canadian kids
There is still more to learn, and no single study has all the answers. But this research moves the conversation away from reacting to asthma once it appears to understanding how it develops in the first place.
For children across British Columbia and Canada, that shift matters. It brings us closer to a future where fewer kids develop asthma, families get clearer answers and prevention, not treatment, becomes the story.
