95% of recent COVID-19 cases in B.C. have been Delta variant, BCCDC report suggests

Researchers predict sharp rise in COVID-19 cases B.C. is well into the fourth wave of the pandemic and could soon see new case numbers over 1,000 per day, according to new modelling.

Vancouver — Nearly every case of COVID-19 reported in British Columbia during the last week of July was the highly contagious Delta variant of the coronavirus, according to data from the B.C. Centre for Disease Control.

The BCCDC's latest report on variants of concern, published Friday, shows 95 per cent of all positive tests in the province during the week of July 25 to 31 were the Delta variant.

The Alpha and Gamma variants - which had each accounted for 40 to 50 per cent of B.C. cases from March until June - were responsible for just two and three per cent of cases, respectively, during the final week of July.

In its report, the BCCDC notes that the latest week of data is only partial and could change as more samples of the virus are sequenced.

However, the partial data continues the ongoing trend seen in recent weeks, in which the Delta variant has supplanted others as the dominant strain in the province.

Delta, along with lower-than-average vaccination rates, has been blamed for the surge in infections in the provincial Interior, which led officials to impose a host of new restrictions on the Central Okanagan region last week.

Experts from the B.C. COVID-19 Modelling Group say restrictions will be needed in more regions if B.C. is going to avoid continued surges, particularly in areas with low vaccination rates.

“This higher transmission rate of the Delta variant is really taking advantage of communities that have lower vaccination rates,” said Dr. Sarah Otto, a UBC zoology professor and a member of the modelling group.

The group's most recent report predicts 1,000 cases a day in B.C. by September without more restrictions.

Notably, Delta is the dominant strain of the coronavirus in every health authority, according to the latest BCCDC report.

The highly transmissible variant was responsible for 99 per cent of infections in Interior Health during the last week of July.

It was responsible for 96 per cent of infections in Island Health, 90 per cent in Fraser Health, 88 per cent in Vancouver Coastal Health and 79 per cent in Northern Health, according to the BCCDC report.

Those numbers are subject to change, however, as more samples from the week in question are analyzed.