Article content The good news is that frequent hand-washing, masks and physical distancing work. Falling daily COVID-19 case counts in Ontario and across Canada testify to that. The bad news? Being hyper vigilant about hygiene could have some serious health consequences down the road. We apologize, but this video has failed to load. Try refreshing your browser, or The downside of clean: Scientists fear pandemic's 'hyper hygiene' could have long-term health impacts Back to video In a paper published in January, members of the Canadian Institute For Advanced Research’s humans and microbiome program raised the possibility the pandemic could profoundly change the human microbiome, making some people more susceptible to chronic conditions and diseases, including asthma and obesity.