Experts note that seasonal impact on the influenza virus is well established and a similar slowdown has been seen in the spread of the SARS outbreak, also caused by a coronavirus. But Prof. of Applied Mathematics at University of Waterloo Chris Bauch, notes that pandemics don’t behave the same way as seasonal outbreaks — and we still have lots to learn about this virus in particular. “Season influenza happens more or less the same time every year. And there are known seasonal factors that cause that,” he explained.
“Vitamin D is a part of certain antimicrobial peptide that our body uses to fight influenza — we get a lot of vitamin D in the summer, for example.” He notes that different diseases can be seasonal for different reasons. “Sometimes it’s related to how susceptible the host is. Sometimes it’s flooded through seasonality and our contact patterns,” Bauch explained. “For example, for some infections spread with kids being crowded together in school in September. There’s a correlation with the school calendar for measles, but we don’t see that for other infections.”
Pandemic influenza, he notes, exhibits different behaviours. “Pandemic influenza can come at any time of the year. We’ve had pandemic waves in the spring and the fall in the pattern in past pandemics… and of course, coronavirus is not influenza and so many of the same things will not apply,” he said.
Bauch says Canadians can expect to heed physical distancing advice until July, noting that halting the spread of the virus is largely dependent on the healthcare system, the availability of a vaccine, and our co-operation.