COVID-19 variants, warning that the pandemic could “resurge rapidly” if public health measures are lifted further.New national public health modelling, released Friday, acknowledges the progress Canada has made in bringing down overall infections and hospitalizations, but emphasizes the imminent threat the arrival of virus variants bring to that progress.“With the emergence and spread of new variants of concern, we are cautioned that unless we maintain and abide by stringent public health measures, we may not be able to avert a rapid resurgence of the epidemic in Canada,” Theresa Tam, Canada’s top doctor, said at a virutal press conference Friday.