TORONTO — Ontario plans to eventually offer booster doses of COVID-19 vaccines to all residents, with the next priority group able to book appointments starting Saturday.
There are 2.75 million people who will become eligible for boosters starting Nov. 6 – those aged 70 and older, health-care workers and essential caregivers in congregate settings, people who received two doses of the AstraZeneca vaccine or one dose of Janssen, and First Nations, Inuit and Metis adults and their non-Indigenous household members.
Eligibility will expand to other groups based on age and risk, with an interval of six to eight months from someone's second dose.
Officials say the broader rollout will happen based on the date of second doses, and they are eyeing early 2022 for the expansion.
Government health officials say the booster dose strategy is based on early evidence of waning immunity over time.
The province plans to focus on booster doses for now, but when the vaccine for kids aged five to 11 is approved - Ontario officials expect that to come this month - the priority will shift to "the rapid provision of first doses for children."
All regions in the province are putting plans in place for the rollout of the vaccine for children, and provincial government officials say every public health unit will offer school-based clinics. Other sites are expected to include mass immunization clinics, pharmacies, primary care doctors, mobile teams and children's hospitals.
More than 250,000 people in Ontario are already eligible for third doses, including certain immunocompromised people and residents of long-term care, retirement homes and other seniors' congregate settings.
Officials say 65 per cent of those already eligible have had a third dose. Either mRNA vaccine can be used for a booster dose, officials say.
They say the reasons vary for including different groups in the next priority cohort. People 70 and older have more waning immunity than those under 70 and a higher risk of severe illness from COVID-19.
Health-care workers have a higher risk of exposure due to their work. People who received two doses of the AstraZeneca vaccine may have had a "gradual waning immune response" sooner than people who got at least one dose of an mRNA vaccine. People in First Nations communities have been disproportionately affected by COVID-19, officials say.
The priority groups identified by Ontario are in line with recommendations from the National Advisory Committee on Immunization, though it said there's no evidence of widespread waning immunity against severe disease in the general population.
Ontario officials say the protection from two doses is still very high for the general population after six months, especially against severe illness and death, so a booster dose would provide additional protection against more mild illness.
Eligible residents can book starting Saturday at 8 a.m. through the provincial portal or phone line, public health units that have their own booking systems, and select pharmacies. Hospital-based health workers should contact their hospital employer.
This report by The Canadian Press was first published Nov. 3, 2021.
Allison Jones, The Canadian Press