Slight decline in COVID-19 patients in B.C. hospitals as bivalent vaccine rollout begins

A sign at the entrance to Surrey Memorial Hospital is seen on Saturday, Feb. 5, 2022. (CTV)

There were 314 test-positive COVID-19 patients in B.C. hospitals as of Thursday, a slight decline from the previous week's total, but comparable to the levels of hospitalization seen for the last three weeks.

The latest decline was driven by decreasing hospital populations in Fraser Health and Interior Health, but offset by jumps in the Vancouver Coastal, Island and Northern health authorities.

This graph shows the number of COVID-positive patients in B.C. hospitals on Thursdays since the province switched to a "hospital census" model for counting hospitalizations in January 2022. (CTV)

Weekly hospitalization totals include both patients with severe cases of COVID-19 requiring hospital care and those who are admitted to hospital for other reasons and test positive incidentally.

Since the province began using this "hospital census" method for counting COVID-19 patients, there have been as many as 985 people in B.C. hospitals on a Thursday, and as few as 255.

FRASER HEALTH DROPS, ISLAND SURGES

Last week, Fraser Health saw a significant increase in its hospital population, enough to bring the province-wide total up even though every other health authority saw its numbers stay the same or decline. 

This week, the opposite dynamic is at play. Fraser Health's hospitalized population dropped from 151 down to 116, the lowest it's been since June.

That decline was offset in the province-wide total, however, by increases in nearly every other region.

Vancouver Coastal Health went from 68 hospitalized patients to 75, Island Health went from 37 up to 56, and Northern Health nearly doubled from 14 to 26.

Only Interior Health saw a decline in its hospital census, going from 48 to 38.

This graph shows the number of test-positive patients in B.C. hospitals by region, over time. (CTV)

NEW CASES AND WASTEWATER

The B.C. Centre for Disease Control reports 574 new lab-confirmed cases during the last epidemiological week, from Sept. 4 through 10.

That's the lowest weekly total B.C. has seen since the BCCDC switched to weekly updates – rather than daily ones – in early April.

The figure comes with a number of caveats, however. Most notably, it includes only lab-confirmed test results, not at-home rapid antigen tests, which are the only type of tests available to most B.C. residents.

The number of weekly cases the BCCDC reports is, therefore, a significant undercounting of the spread of the coronavirus in the province, and data released last month by the independent B.C. COVID-19 Modelling Group suggested the undercounting has been getting worse.

As of mid-August, the group estimated that the weekly caseloads were off by roughly 100-fold, up from roughly 40-fold in late April.

If the modelling group is right and B.C. is seeing 100 times as many infections as it has reported, the last epidemiological week would have seen roughly 57,400 new cases, or 8,200 per day.

The continued decline in weekly case counts doesn't necessarily match the trend in wastewater surveillance, which saw "stable" concentrations of the coronavirus in Metro Vancouver during the week of Sept. 4 to 10, according to the BCCDC's latest situation report. 

DEATHS

Thursday's update also included 16 new deaths among people who had tested positive for COVID-19 within the 30 days before they died.

The death count the BCCDC reports each week tends to be revised higher over time, as data becomes more complete. Not all of the deaths temporally linked to COVID infections are caused by the disease, however.

Since the BCCDC began reporting "30-day, all-cause mortality" on April 2, a total of 1,194 deaths have been linked to COVID-19. The underlying cause of death for 126 such cases has yet to be determined by the province's Vital Statistics agency.

Of the remaining deaths, 458 were caused by COVID-19, according to Vital Statistics, while the remaining 610 were not.

VACCINATION

Last week, the provincial government announced details of its plan for rolling out new, bivalent vaccines that offer targeted protection against the Omicron variants of SARS-CoV-2. 

Booster doses of the new vaccines are being offered to everyone age 12 and older, with the first invitations to book appointments expected to go out by the end of last week.

Vaccination clinics operated by health authorities are scheduled to begin opening on Monday, with the province expecting to have the capacity to administer 280,000 shots per week by the end of September.

The rollout of the new vaccines is not yet reflected in the BCCDC's data. The province administered just 23,524 new doses of vaccine during the week that ended Sept. 10.

Of that total, 9,178 were fourth doses, 11,484 were third doses, 919 were second doses and 1,912 were first doses.