Dr. Karen Grimsrud, seen here in 2006, is leaving her post as Alberta's acting provincial health officer when her contract expires in August. (CBC)

Alberta's health minister says money, and not the government's recent health-care reforms, is to blame for the departure of four of the province's top doctors.

"This is not speaking negatively of the doctors who chose to leave but there is a limit as to what the government of Alberta can pay for certain positions," Health Minister Ron Liepert said on Tuesday morning.

Dr. Karen Grimsrud, the acting provincial health officer, Dr. Gloria Keays, the deputy provincial health officer, and Dr. Ameet Singh, the infectious-disease medical consultant, are all leaving the department when their contracts expire in August.

A fourth senior public health official, Dr. Shainoor Virani, stepped down earlier this year. Liepert said the province failed to sign the doctors to new deals over the past few months.

'We need to make sure that we don't leave the province and patients vulnerable to open positions in our public health area.'—Dr. Darryl LaBuick, Alberta Medical Association

"There was a negotiation of contracts. The public health doctors are in short supply across the country," he said.

"There were, as I understand, significant opportunities for these doctors and as much as we hate to lose them, this is just normal process where if you can find a better opportunity, you take it."

Liepert did not have details about the doctors' wages or who has hired them away from Alberta Health and Wellness.

Public health officers play key roles in managing infectious diseases and immunization issues, such as the recent mumps outbreak in Alberta.

"To lose that many physicians in this area is fairly critical," said Dr. Darryl LaBuick, president of the Alberta Medical Association. "We need to make sure that we don't leave the province and patients vulnerable to open positions in our public health area."

Alberta Health Minister Ron Liepert says the province's health-care reforms have nothing to do with the departure of four senior public health doctors. (CBC)

Liberal health critic Dr. David Swann, a former medical health officer himself, said replacements will be hard to find.

"Since we haven't been able to fill the provincial health officer position in the last year, it raises serious questions about whether we can fill any of the other positions now," said Swann.

NDP Leader Brian Mason speculated the departures were related to the government's policies.

"It indicates a very strong reaction against the direction of the government, which clearly is toward private health care," said Mason.

Last month, Liepert disbanded Alberta's nine health authorities to form a superboard. The health minister said Tuesday that the situation has nothing to do with the recent reorganization.

Liepert was asked about failing to match demands of the doctors, while the Alberta cabinet voted itself a wage increase of about 30 per cent at the same time.

"That door is closed," he said.

With files from the Canadian Press