What you need to know about the fourth COVID shot

Immunization is the main weapon Hamilton public health plans to use against increasing COVID spread.

The province gave the city extra ammunition by opening up fourth shots to Ontarians age 60 and older starting Thursday. It also expanded eligibility to adult First Nation, Inuit and Metis individuals and their non-Indigenous adult household members.

Those already able to get a fourth dose include residents of seniors' homes and older adults in congregate-care settings, as well as immunocompromised Ontarians aged 12 and over.

We're all really looking at those booster doses right now," Hamilton medical officer of health Dr. Elizabeth Richardson said Monday. That is the most important piece in terms of reducing severity for individuals ... for those around them and for the community as a whole."

How to get your fourth shot

Hamilton does not use the provincial booking portal. Starting at 8 a.m. on Thursday, go to hamilton.ca/getyourvaccine or 905-974-9848, option 7, for an appointment.

Check pharmacy locations at covid-19.ontario.ca/vaccine-locations.

First, second and third doses can still go to city clinics without an appointment.

Why do I need a fourth shot?

Immunity fades over time so the extra dose bumps up protection against infection and severe outcomes.

Those of us who have now had three doses, time is going on which means our immunity is waning," Dr. Bart Harvey, an associate medical officer of health, said Monday. The shot is boosting that immunity to decrease the current surge but also the potential for a much larger surge that's worried to come perhaps in the fall or in the winter."

Do I need it if I've had COVID?

Those who have been infected with COVID are still recommended to get vaccinated.

People's immunity to that infection will wane and eventually get down to zero so they become susceptible to becoming infected," said Harvey. Infection with this virus provides temporary immunity and certainly not lifelong immunity."

When should I get the shot?

Ontario recommends waiting five months - 140 days - after the third dose because a longer interval has been shown to provide better immune protection. However, you can choose to get it after three-months - 84 days.

The National Advisory Committee on Immunization (NACI) recommends six months - 168 days. However, it says the interval can be shortened because of rising COVID transmission.

Immunocompromised Ontario youth aged 12 to 17 need to wait six months.

Do vaccines work?

Vaccines provide some protection against infection but really shine when it comes to preventing severe outcomes such as hospitalizations, admissions to the intensive care unit and death.

People that have had a third dose were 61 per cent less likely to be infected by Omicron compared to those who only had two doses, so there is clearly an advantage," said Harvey.

The Ontario COVID-19 Science Advisory Table shows on its dashboard the difference vaccination makes.

Cases per 1 million population per day are 304 for the unvaccinated compared to 200 for those with at least two doses - a 34 per cent reduction.

For hospital occupancy, the rate is 264 for those with no shots compared to 64 for the fully vaccinated - a 76 per cent reduction.

The biggest difference is ICU occupancy with a rate of 58 for the unvaccinated compared to nine for those with at least two doses - an 85 per cent reduction.

Joanna Frketich is a health reporter at The Spectator. jfrketich@thespec.com