Delta COVID-19 variant to make up nearly all B.C. cases within ‘weeks,’ says UBC modeller

A UBC professor who specializes in modelling COVID-19 transmission says it won’t be long before the highly-contagious Delta variant makes up virtually all new cases in the province.

“In the next week or two,” mathematical biologist and member of the B.C. COVID-19 modelling group Sarah Otto told Global News.

“Already, we’re seeing that it’s at around two-thirds of the cases, and with the spike in the Interior, it’s only a couple of weeks.”

Data released by the BC Centre for Disease Control showed genetic sequencing had confirmed the Delta variant in 60 per cent of B.C. cases as of July 24.

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Otto said the number likely under-represents the reality of Delta’s spread.

On Friday, Canada’s Chief Medical Health Officer Dr. Theresa Tam warned the country could be at the start of a “Delta-driven fourth wave” of the pandemic.

Internal documents from the U.S. CDC obtained by the Washington Post this week suggested Delta was as contagious as chickenpox.

While vaccines have proven highly effective at preventing serious illness or hospitalization among the immunized, the CDC documents also suggested that vaccinated people may still be able to transmit Delta.

Data from B.C. released last week showed 96 per cent of cases between June and July were among people who were not fully vaccinated.

B.C. reported 243 cases of COVID-19 on Friday, more than double the 100 new cases reported the week before.

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More than half of the new cases were in the Interior Health region, where officials have declared an outbreak in the Central Okanagan and reimplemented restrictions.

“The vaccines protect those of us who are vaccinated, but what we’re seeing is the communities with a lower vaccination rate are really, really much more susceptible,” Otto said.

“Here in British Columbia, communities with vaccination rates of around 70 percent are five times more likely to have cases than communities that are closer to 90 percent. So that’s where we’re seeing the difference in community after community after community.”

Some of B.C.’s lowest vaccination rates remain in the interior and northeast. In the Enderby local health area, just 60 per cent of people have had their first dose, while Creston is at 63 per cent.

Just 53 per cent of people in the Peace River South area have had one dose.

Otto warned that hospitalization rates have also begun to creep up again, and according to her modelling, the province could top the number of people in hospital at the peak of the third wave if case rates continue to climb at their current speed.