Unvaccinated COVID patients more likely to need help breathing in Waterloo Region

WATERLOO REGION — Upwards of half the recent COVID-19 hospitalizations in Waterloo Region are driven by just 10 per cent of the population that’s unvaccinated.

While residents who are fully vaccinated can still become infected with the virus, their risk of being hospitalized or sick enough to need help breathing is far lower during the pandemic’s latest wave.

But since most local residents are fully vaccinated, some will still end up in hospital — though officials stress that doesn’t mean the vaccine isn’t doing its job at protecting against COVID-19.

“The mistake often made is that vaccination must be 100 per cent effective in preventing infection to be considered ‘effective,’ ” said Dr. Kevin Stinson, program manager of infection prevention and control at St. Mary’s General Hospital and Waterloo-Wellington lead for the province’s Regional Infection Control Networks.

The Kitchener hospital was caring for 22 COVID-positive patients on Tuesday morning. Five of them, or nearly 23 per cent of the total, were unvaccinated, climbing to two out of three patients who were severely ill and requiring intense intervention to breathe.

Reducing the likelihood of serious illness and death after an infection is the COVID-19 vaccine’s main role, Stinson said.

“This effect is especially seen after the first two doses. Booster doses then play a major role in reducing the overall risk of acquiring COVID-19 if exposed,” he said. “Even as those preventative responses fade after several months, it never reduces your protection to zero.”

During the most recent Omicron wave, about 30 to 50 per cent of patients with an acute COVID-19 infection on any given day in the region’s hospitals are unvaccinated, Stinson said in an email.

However, he added there are two important things to consider. First, almost nine out of 10 eligible residents are fully vaccinated with at least two doses. That means the risk of hospitalization is significantly higher in unvaccinated groups, which account for three to five out of 10 people in hospital.

Then there is severity. The risk of severe illness requiring oxygenation or intubation is about 20 per cent for the fully vaccinated, and topping 70 per cent for the unvaccinated.

“We can see that vaccination reduces your overall risk of hospitalization, and the risk of severe disease if you are hospitalized,” Stinson said.

At St. Mary’s on Tuesday, there were 14 patients with mild illness — meaning they didn’t need supplemental oxygen. Of those, 11 had three or more vaccine doses; the three others were split: one had two doses, one had one dose and one was unvaccinated.

Another four had moderate illness requiring a low flow of supplemental oxygen. Two had two vaccine doses, two were unvaccinated.

Of the patients with severe illness requiring high-flow oxygen or ventilation, one had three or more doses and two were unvaccinated.

Cambridge Memorial Hospital’s active COVID-19 cases Tuesday included one unvaccinated patient, one patient with one dose, and three with two doses. A week earlier, there were six unvaccinated patients and two with two doses. Both days, there was one unvaccinated patient who was critically ill with COVID, compared to none who had at least one shot.

Grand River Hospital reported 22 COVID-positive patients in hospital: five with four doses, five with three, seven with two doses, two with one shot, and three whose vaccine status wasn’t known or who declined to answer.

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