Public health officials and infectious disease experts are urging Canadians to ensure their vaccinations are up to date as clusters of mumps are investigated in Ontario and Alberta, and measles cases are probed in Nova Scotia.

The viral infections are both covered by the measles-mumps-rubella or measles-mumps-rubella-varicella vaccines -- and experts say those between the ages of 18 and 35 need to ensure they've had two doses of the shots to bolster their immunity.

Public health officials in Toronto say 17 cases of mumps have been confirmed in the city, all involving people between 18 and 35 who frequented west-end bars.

A Public Health spokeswoman says 60 per cent of the people in those cases were not immunized or were under-immunized.

In Alberta, officials say four cases of mumps have been confirmed among students at the University of Alberta in Edmonton, and a hockey team based in Medicine Hat has had seven players and a coach contract mumps.