The first COVID-19 booster shots have been rolling out in Nova Scotia since late 2021. Most Nova Scotians age five and older can get their first booster 168 days after completing their second dose. Pregnant and immunocompromised people are eligible 140 and 120 days after, respectively. (Scroll below for an update on the fall booster rollout in Nova Scotia.)
Are you curious about why booster shots are needed? Wasn’t the primary two-shot series recently considered “fully vaccinated”?
“Some vaccines that we take, we get one or two doses, and the protection lasts our whole life,” says Dr. Joanne Langley, co-chair of the Canadian COVID-19 Vaccine Task Force and head of Pediatric Infectious Diseases at the IWK Health Centre. “For these, we don’t plan on boosters—an example would be for measles.”
For other vaccines, boosters are a normal part of ongoing protection. The tetanus and diphtheria vaccine requires a booster every 10 years, for example.
For the COVID-19 vaccine, says Dr. Langley, the first doses you get are very good at stimulating your immune system to develop a response.
“But your immune system needs reminders. We have evidence now that if people don’t have that third dose and COVID is circulating, you are more likely to be infected and more likely to have severe outcomes. We really need that third dose to continue the protection that was initiated by the first and second dose.”
Does this mean you’re going to need to keep having COVID booster shots on a regular basis?
“From a population immunity point of view, it might be like influenza where you need a different reminder each year,” Dr. Langley explains. “While we don’t know for sure that we’ll need annual boosters, for this part of the pandemic it seems like we need regular boosters.”
Booster doses of the COVID-19 vaccine work by helping to raise the levels of antibody present in your bloodstream. These antibody levels correlate with your level of protection against severe outcomes if you become infected with the virus.
“We know from antibody studies that your body stops making them at that high level about five or six months after that second vaccine.”
Is a booster necessary if you’ve had a COVID-19 infection as well as your primary series of vaccine?
“The immunity you get from a combination of vaccines and being exposed to the virus circulating in the community is called hybrid immunity. On the positive side you do get an increase in your immunity, and it’s probably qualitatively improved compared to repeated vaccines,” Dr. Langley says. “But you trade that off against the increased risk of some of the severe outcomes.”
Those severe outcomes include long COVID, or ongoing symptoms after you’re over the acute COVID-19 infection. Dr. Langley cautions these symptoms can have life-altering effects, such as extreme fatigue, ongoing headaches, or central nervous system problems like a decrease in memory or cognitive ability. “These are symptoms that interfere with one’s ability to carry on life the way you did before you had the infection.”
Getting boosted can help reduce that risk.
Fall booster update
Public Health is advising Nova Scotians aged 12 and older who are eligible for a their fall dose to receive a bivalent vaccine rather than the original COVID-19 vaccine. The Moderna and the Pfizer bivalent vaccines are both now available in Nova Scotia and provide protection against the original strain of COVID-19 and Omicron variants. The Pfizer bivalent vaccine is available for people aged 12 and older; Moderna’s bivalent vaccine is available for people 18 and older. If you’re eligible for both, don’t wait around for one brand over the other – book the first available appointment.
Timing wise, you can book your booster if it’s been 168 days since your last COVID-19 vaccine or 168 days since you’ve had a COVID-19 infection. If you are moderately to severely immunocompromised or aged 70 and older, you can book your booster 120 days from the date of your last shot.
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Nova Scotia quick links
Info if you test positive for COVID-19
Report and Support screening form
Drop-in vaccination clinics in Nova Scotia
Getting vaccinated against COVID-19
Getting tested for COVID-19
Get rapid tests
Info on long COVID
Mental health and well-being
Nova Scotia COVID-19 resources