@duncan
You've probably heard of CanLyme - a national, Canadian, non-profit charitable organization run by volunteers:
https://canlyme.com/
Couldn't find prevalence on the CanLyme website. I'm thinking it has to be there somewhere...
Government of Canada surveillance re Lyme disease from 2009 to 2017 = 144 cases in 2009, 2025 cases in 2017
https://www.canada.ca/en/public-hea...yme-disease/surveillance-lyme-disease.html#a3
I would expect that as with some other health issues, Lyme Disease in Canada is
highly under-reported, but this study says not; the authors do say they can't pin down the "precise degree of under-reporting".
"Conclusion
Our comparisons of human case LD incidence, as reported in surveillance and as suggested by canine seroprevalence, in the US and Canada do not support the idea that there is a high degree of under-reporting (< 10% of cases reported) in Canadian human case surveillance. Even if it could be argued that these comparisons are themselves plagued by under-reporting, the extensive surveillance efforts conducted in Canada mean that we have a strong understanding of where LD risk is occurring, how it has evolved and in what ways it is similar to, and different from, that occurring in neighbouring US states. It is clear that, as for other reportable disease surveillance programs, under-reporting of LD occurs in Canada, and in part the surveillance is designed to discover this. However, tick surveillance data, combined with evidence from serological studies in dogs, do not suggest high levels of under-reporting in Canada. We speculate that the rate of under-reporting in Canada may be similar to that seen in regions where LD is emerging in the US [
20]. The precise degree of under-reporting is unknown, and further prospective studies are needed to measure this."
https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-019-7219-x
I still have my doubts about the level of under-reporting. Governments have gone from saying there is no Lyme Disease in Canada, to saying there are essentially a couple thousand cases two years ago. We know for instance that harms from medical devices are under-reported. The true numbers for several health issues , especially stigmatized ones could be down played.