As cases of the flu continue to grow in Alberta, the struggle to convince health-care workers to get vaccinated continues.

Health officials have been trying for years to convince staff that they too should get their shots.

But only around half have listened, according to Alberta Health Service numbers.

"There's room for improvement, a lot of improvement," said Dr. Judy MacDonald, Calgary's medical officer of health.

The latest AHS report shows only 50 per cent of staff have been vaccinated so far this flu season.

By the end of last year's flu run, 61 per cent had received their flu shots.

That's a far cry from the target of 80 per cent.

Dr. Judy MacDonald, a medical officer of health with the province, says more health care workers need to be immunized against the flu. (Stephanie Wiebe/CBC)

"I would be completely in favour of mandatory influenza immunization for people that are directly interacting in health care, which includes contractors, volunteers and staff," said Margaret Gray, an infectious disease pharmacist at the University of Alberta Hospital.

She says by not getting vaccinated, staff who have been exposed to the flu but don't have symptoms can still spread the virus

"So there's a risk that you make patients that are already immunocompromised sicker and put their health and potentially their lives at risk," she said.

British Columbia brought in a policy in 2012 requiring health-care staff to get immunized or wear a mask for the duration of the flu season.

Vaccination rates for workers there increased from 38 per cent to between 75 and 80 per cent as a result.

Alberta Health says it is not considering a similar policy at this time.