TORONTO -- The transition from Ontario's old health cards to new ones with photographs could leave some people without coverage in an emergency, especially if they ignored notices to update their card.

There are still more than 3.5 million Ontario residents with the old red-and-white health cards that have no expiry date and no picture.

One of them was CTV health reporter Avis Favaro, who discovered her Ontario Health Insurance Plan card had been cancelled when she went to a Hunstville walk-in clinic after suffering a bad reaction to an insect bite while on vacation.

Favaro was told she would have to pay $60 cash to see a doctor, and was directed to a nearby cash machine because the clinic would not accept credit or debit cards.

Health Minister Deb Matthews said there have been no changes to the program to move people over to the new cards, and wants people to know they can still use their old health cards.

"I think a lot of people are seeing the story and are worried that their health care somehow is in jeopardy if they have a red and white card," Matthews said in an interview.

"Nothing could be further from the truth."

NDP health critic France Gelinas supports the transition to more secure OHIP cards, but said "health care is a right" and no one should ever be denied coverage.

"This is not how you do a transition from an old system to a new system, without giving any warning on a service as important as medicare," Gelinas said in an interview.

"This is not acceptable, and makes no sense."

The Progressive Conservatives said Favaro's case was very concerning.

"I think, generally speaking, it's a good idea to encourage people to replace those cards, but to do so in such an arbitrary manner with potential serious consequences for people is not the way to go about effecting this kind of change," said Deputy PC leader Christine Elliott.

"That's not the way health care is meant to operate in Ontario."

The new photo health cards were introduced in 1995, and so far 75 per cent of Ontario residents have been switched from the old cards to the new.

The red-and-white cards are still valid and can still be used at hospitals and clinics, and medical staff can call a 24-hour line to verify the status of any health card that is presented by a patient.

"Everyone, whether they have a photo card or a red-and-white card, will continue to get the service they're getting now," said Matthews.

"If there is a situation where a red-and-white card is denied, but they are still entitled to OHIP coverage, absolutely they will be reimbursed."

Government officials refused to comment on any specific case, but said there had been only two complaints about cancelled health cards logged with ServiceOntario in the past 12 months.

There's still no word on how many tried to get reimbursed for health-care expenses they had to pay out of pocket after their card was rejected.

Matthews said people are sent three notices telling them to register to get a new health card with a photograph and a five-year expiry date. If the card holder doesn't respond, and the health card hasn't been used in seven years, the government will suspend it.

"This is done to protect the integrity of our system," Zita Astravas, Matthews' press secretary, said in an email.

Many people never get an annual checkup, and thousands have no family physician nor the patience to wait in hospital emergency rooms for treatment, so they go years without using their health card, said Gelinas.

"I'm sure people who live in an underserviced area and don't have a family physician because there's none to be had, and have not had the patience to wait 18 hours -- the average wait in an emergency department where I live -- simply went without," she said.

"If something happens where they need health care, this is a hell of a time to find out that you're not covered."

"Generally speaking, if someone has received care after their card was cancelled and upon review their cancellation was a mistake, they may be eligible for a reimbursement upon their health card renewal," said Astravas.

The province replaces about 225,000 of the old red-and-white health cards with the new photo cards every year. The government said about 150,000 people will apply for an updated health card each year without being asked to do so.