The number of active COVID-19 cases in Delta fell again last week to its lowest point since February.
Every Wednesday, the BC Centre for Disease Control releases a map showing the geographic distribution of COVID-19 cases by local health area of residence. The latest weekly map shows Delta had 104 cases for the week of May 9 to 15, 65 fewer than the week previous.
Delta’s case total has fallen for four of the last five weeks, only adding 28 cases the week ending May 1. Previous to that, the numbers had been climbing for 10 straight weeks before hitting a record high of 262 the week ending April 10.
The overall number of active cases in the Fraser Health region decreased for the fourth straight week to 2,360, down 625 from the week previous.
All but one of the 13 local health areas in the Fraser Health region saw decreases from the previous week, most notably in Surrey (1,094, down 315), Abbotsford (315, down 93) and Langley (115, down 46).
Wednesday’s map release came as health officials reported 521 new COVID-19 cases in the province over the past 24 hours — the first time cases rose over 500 in the past six days — 335 of which were in the Fraser Health region. Wednesday’s cases brought the total number of active cases in B.C. to 4,815, with eight new deaths. B.C. has seen a total of 140,596 cases and 1,658 deaths since the pandemic began.
Recently, health officials announced they would begin regularly releasing neighbourhood-specific COVID-19 case counts, test positivity rates and immunization rates. Maps released last Wednesday (May 12) shows North Delta had an average seven-day rate of between 20.1 and 40 cases per 100,000 people for the week of May 4 to 10. The rest of Delta, by comparison, had a rate of between 0.1 to 5 cases per 100,000 people. (Updated maps had not been released as of the Reporter’s deadline.)
The maps indicate test positivity rates in Delta for the week of May 4 to 10 varied widely across the three community health service areas (CHSAs). Unsurprisingly, North Delta had the highest rate, between 10.1 to 20 per cent, while Tsawwassen (comprising the Delta community and Tsawwassen First Nation) had the lowest rate, between 1.1 and 2 per cent. Ladner, meanwhile, had a rate of between 3.1 and 5 per cent.
Vaccine coverage was more even across the CHSAs. Over 80 per cent of adults aged 55 and over, and between 41 and 60 per cent of adults 18, have received at least their first does of vaccine. Coverage of adults 18 and over was higher in Tsawwassen — between 61 and 80 per cent.
The most recent BC CDC map showing total cumulative cases by local health area from the start of the pandemic through the end of April 2021 shows there were a total of 4,327 COVID-19 cases in Delta through to April 30, meaning there were 990 new cases last month, compared to 614 in March.
The map also shows there were 7,043 new cases in Surrey in April, compared to 4,406 in March, and 17,086 new cases across the Fraser Health region, compared to 10,554 in March. Vancouver Coastal Health, meanwhile, had 7,497 new cases in April, compared to 5,726 in March.
As of noon on Thursday (May 20), there were no outbreaks at any Delta long-term care, assisted living or independent living facilities, no public exposure notifications, and no Delta businesses had been temporarily closed due to COVID-19 spread among workers.
Provincial Health Officer Dr. Bonnie Henry announced April 8 that workplaces with three or more people who have COVID-19 and likely transmission in the workplace will be ordered to close, unless it is in the overriding public interest to keep it open. The closure generally last for 10 days unless otherwise determined by health officials.
Meanwhile, Fraser Health’s website listed exposures at 14 Delta schools as of Thursday morning: Brooke Elementary (May 11 and 12), Burnsview Secondary (May 4, 6, 10, 11, 12, 13, 14 and 17), Chalmers Elementary (May 6, 7 10 and 11), Delview Secondary (May 12), Gibson Elementary (May 11), North Delta Secondary May 6 and 11), Pinewood Elementary (May 6, 7, 11, 12 and 13), Richardson Elementary (May 6, 7, 12 and 13), Sands Secondary (May 10 and 11), Seaquam Secondary (May 10 and 13), South Delta Secondary (May 12, 13 and 14), Sunshine Hills Elementary (May 6 and 7), Immaculate Conception School (May 13 and 14) and Southpointe Academy (May 10, 11, 12 and 13).
Fraser Health defines exposure as “a single person with lab-confirmed COVID-19 infection who attended school during their infectious period.” Two or more individuals is defined as a cluster, while an outbreak describes a situation involving “multiple individuals with lab-confirmed COVID-19 infections when transmission is likely widespread within the school setting.”
On May 7, Fraser Health released a retrospective analysis of COVID-19 cases in schools aimed at helping determine clusters and transmission dynamics. The report analyzed cases in students and staff at both public and private schools reported to public health over a 66-day period between Jan. 1 and March 7, 2021.
The report shows there was a cumulative total of 830 cases in the city during that time, 88 of them students attending schools in Delta, and clusters or outbreaks at seven local schools, all of them in North Delta. There were eight known incidents of in-school transmission; seven were student-to-student and one staff-to-staff. One of those student-to-student cases was a variant of concern.
Overall, of the 2,049 cases found among school staff, teachers and students in the health region, Fraser Health considers 267 –13 per cent – to be school-acquired. Of those, 88 led to community or household spread.
However, Fraser Health data shows there were an additional 333 cases with “suspect acquisition in school” that were not included in the 267 confirmed school acquired cases. If those cases were added to school-based infections, that would more than double the percentage teachers and students who caught COVID-19 at school from 13 per cent to 29 per cent.