Ontario’s top doctor has announced individuals 18 and over will be eligible to book a booster shot as of Jan. 4 at 8:00 a.m.

“Ontario will expand the booster dose eligibility for all Ontarians 18 years of age and older. Please get your booster dose as soon as you're eligible,” Chief Medical Officer of Health Dr. Kieran Moore said at a provincial COVID-19 update on Friday.

As more Ontarians become eligible for booster shots, Moore said discussions are underway in the province to potentially redefine what it means to be fully vaccinated – whether two doses or three doses qualifies.

“We certainly are encouraging all those that are eligible at present for the third dose to get theirs and we'll be following the immune protection of a third dose against Omicron to understand what immunologically represents the best protection. That may change the definition of what is fully immunized,” Moore said.

Given how fast the Omicron variant is spreading, Moore said a robust third dose strategy is critical in Ontario. With 10 per cent of COVID-19 samples now testing positive for Omicron, Moore said the variant could become the dominant strain in the next month.

“It's anticipated that we'll have a significant rise in the coming weeks,” Moore said.

Eligible individuals will be able to book their third dose appointment through the provincial portal or by calling the provincial vaccine contact centre. Boosters will be available at vaccination clinics, select pharmacies and primary care settings.

Appointments should be booked approximately six months, or 168 days, after a second dose.

As of Dec. 13, approximately 5.5 million Ontarians aged 50 and over will be eligible to receive their booster dose.  

Currently, 70,000 COVID-19 doses are being administered every day in Ontario, but by expanding booster shot eligibility, Moore said health officials would like to reach 120,000 doses a day.