The CEO of the Windsor-Essex County Health Unit is calling it a "significant" shift.
Theresa Marentette says individuals 80 and over who received their first dose of the COVID-19 vaccine last week and on Monday will have to wait longer to receive their second dose.
She says the health unit is following direction from the province, and is cancelling all scheduled second dose appointments.
Marentette says the health unit is still working on logistics but plans to call the 973 seniors to let them know when their second dose appointment will be.
"We would have really liked to give this population of over 80 both doses but the ministry directive is quite clear and they are wanting us to immunize as many people as possible so everyone has a first dose by June," says Marentette.
The province updated its vaccine plan for the Pfizer vaccine and now says individuals will wait 16 weeks after their first dose, to receive their second dose instead of three weeks.
Marentte says seniors who have a second appointment scheduled, can expect a call from the health unit.
"It will be important to say to them that their appointment that they did have scheduled is cancelled and we'll either give them an appointment for four months down the road with a location or we'll tell them that we'll be in touch with them again," she says. "So we have to just figure out the logistics internally on what the four months really looks like and if the locations are still set."
She adds the change from the province will not impact long term care or retirement homes.
"The direction from the ministry does not include residents of long term care or retirement homes who will continue to get both doses," says Marentette.
The health unit plans to talk to its municipal partners Tuesday about the current vaccination sites.
According to Marentette, the partnerships with Windsor and Leamington have start dates but as of now, there are no end dates for the sites at the WFCU Centre and the Nature Fresh Farms Recreation Centre.