Amid controversy over how the vaccination plan has been handled, the province's chief public health officer is explaining how decisions were made.

"I completely understand and empathize with Nova Scotians who are feeling confused," said Dr. Robert Strang Tuesday.

He says until last Friday there was no indication of a vaccine shortage in the country but once there was a shortage established, at-risk groups were given priority.

"Some people have been pushing us to go for all school-aged groups, even though they're not one of the risk groups for an urgent need for vaccine," says Strang.

"But we would not have enough vaccine for them either.

He says assessments of the vaccination plan are happening daily and details of when the next priority groups can line up could come as early as Wednesday.