COVID-19 vaccine prevents illness, not infection: Ontario health officials

While the country celebrates the first COVID-19 vaccinations on Monday as a momentous turning point in the pandemic, Ontario Health officials warn we’re not out of the woods just yet.

In the daily COVID-19 briefing, the province’s Associate Chief Medical Officer of Health said it is important to note that while studies have shown the vaccine will prevent people from becoming ill, they have not yet shown that it prevents infection.

“Even if somebody gets vaccinated, they may have an asymptomatic infection so they still could be infectious to others,” said Dr. Barbara Yaffe, adding that studies about the vaccine’s potential to protect against infection are ongoing.

“Even when somebody is vaccinated, they need to protect themselves and others from spreading the infection,” she said.

In addition, Yaffe said it will still be several months before we see widespread benefits of the vaccinations.

“Usually for infectious diseases … 70 to 80 per cent of the population has to be vaccinated for what we call herd immunity,” said Dr. Barbara Yaffe. We’re not going to get there with this vaccine until probably the summer [of 2021].”

Yaffe added that spread of infection in the general population will not be prevented until we hit herd immunity and cautioned that public health protocols still need to be followed.

Chief Medical Officer of Health, Dr. David Williams, added that he hopes the arrival of the vaccine will give people experiencing “COVID fatigue” renewed energy to buckle down, follow all necessary measures and get through this difficult time rather than abandon safety protocols.

“You can start to see on the marathon, the finish line coming. [People may feel] ‘I don’t have to keep doing this kind of thing for the next two or three years, I can see that there’s a potential end in sight’,” he said. “I would see it as a chance to say ‘we can do this, lets refocus and get [cases] back down again.”

He added that it is best that the population is vaccinated without “massive outbreaks everywhere” and reiterated the need for strict adherence to public health measures.

“We need to come down off this second wave so we can enter the vaccination phase full-tilt in a low incidence prevalence rate,” he said.