Ontario doesn't plan to expand its H1N1 vaccination program to school-age children next week and will continue immunizing only those in priority groups.

"We need to protect our most vulnerable populations," Health Minister Deb Matthews told reporters at a Toronto news conference on Friday.

"That’s why our experts are telling us to immunize people in priority groups only."

Matthews has suggested that school-age children may be next in line to receive the vaccine as Ontario receives more doses. But it's not clear when there will be enough doses to expand the vaccine rollout.

Matthews did not specify when the vaccination program would be expanded to include other groups, saying only that all Ontarians will get "the care they need as quickly as possible."

Last Friday, Dr. Arlene King, Ontario's chief medical officer of health, announced only people in priority groups would be immunized this week due to a shortage of the vaccine.

"I urge all Ontarians and all health-care providers to respect the experts' guidelines and directions. We've been assured that, in time, there will be enough vaccine for everyone who wants it and needs it." Matthews said.

Matthews also tried to shift some of the responsibility for uncertainty around the vaccine rollout to the federal government.

"I have had repeated conversations with the federal health minister [Leona Aglukkaq] to ask for clarity about the availability of the vaccine. I'm committed to continuing those conversations until we get the answers we need to plan."

The province will receive 770,000 doses of the vaccine next week, Matthews said. Of that total, 375,000 contain adjuvant, a chemical that bolsters the immune system.

The remaining 395,000 doses are adjuvant-free and have been earmarked for pregnant women due to a lack of research on the safety of the substance in women who are expecting.