Ottawa, July 31 (RHC)-- Canadians under the age of 39 make up a clear majority of new cases of COVID-19 in Canada, health authorities said, warning young adults they are not "invincible" against the disease.

"Recent national surveillance data show that young adults aged 20-39 years of age account for the highest incidence rates across all ages in Canada," Canada's chief public health officer Theresa Tam said in a statement.

For the week ending July 22, the incidence rate was highest among young men and women aged 20-29 (14.4 and 13.8 cases per 100,000 people respectively), followed by those aged 30-39.

"Younger Canadians are not invincible" to the disease, Tam warned, noting that it is not only the elderly who are at risk of serious health problems if infected.

She pointed out that, of the cases of COVID-19 reported to public health last week, 63 percent involved people under 39 years of age, of whom roughly one-third were hospitalized.