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Please see our full report for more details and simulation results. The only way things can return to normal in BC is if a large portion of our population obtains immunity to the virus, either through infection or through vaccination. Currently a small fraction of British Columbians are immune to COVID-19: approximately 1 in 5 of us have received at least one dose of vaccine, and a much smaller number have had the infection.

There has been a lot of discussion about “variants of concern” (VOC) internationally and across Canada. One of the most important concerns is that SARS-CoV-2, the virus that causes COVID-19 and so has caused the COVID pandemic we are all facing today, has found ways to become more transmissible. We recently posted modelling work on what a higher transmission rate would look like for the number of infections. In a place like British Columbia, where cases of our usual type of COVID-19 have held steady in past weeks, a higher transmission rate means that cases would grow.

After many long months with no treatment or vaccine available, and widespread social distancing the main tool for fighting the pandemic, there are now four different vaccines approved that are effective for COVID-19. Phase 3 trial data and experiences since then show that the Pfizer and Moderna vaccines are safe and highly effective at preventing disease. Even better, preliminary results point to them also being effective at preventing infection, which means they will block transmission of the virus.

Background The appearance of new COVID-19 Variants of Concern has jurisdictions around the world scrambling to determine whether variants are already circulating within their communities. Here we present modelling results that indicate how many active cases are likely circulating within a community before the first variant is detected and how this number depends on the sampling strategies used by Public Health authorities. A new Variant of Concern (VOC) was described in the December 21st Public Health of England report 1, sounding the alarm that a more transmissible form of the SARS-CoV-2 virus that causes COVID-19 had emerged (“B.

Here we illustrate the kind of reported case trajectory that we may see if a higher-transmission variant, such as the B.1.1.7 variant that has been rising dramatically in frequency in the UK, becomes established in Canada. Volz et al estimate that B.1.1.7 has a substantial transmission advantage - a 40-80% increase in the reproduction number, for example. An increase like that in the transmission rate is worse than a higher severity or mortality rate, because so many more people can get infected.

Contact tracing, combined with social distancing measures, can be an effective strategy to keep COVID-19 numbers down (Kucharski et al. 2020) and has been the main strategy used in many parts of Canada. Starting with a team of about a dozen contract tracers, British Columbia, for example, has been ramping up towards a thousand tracers, who collectively have helped to bend down the numbers of COVID-19 cases in the province.

Currently things appear to be returning to normal in British Columbia. While in other parts of North America the pandemic rages, here, although cases are growing, the number remains small. Schools in BC were closed abruptly in March in response to COVID-19, but were then reopened in June without leading to disaster. The pandemic has appeared to be under control for most of the summer. With this background, the BC Government announced the reopening of schools for September.

So far, BC has been one of the best places to live in the world during the pandemic. When COVID-19 first came here, it was controlled for weeks with strong contact tracing, testing and reporting, and changes to long-term care. Travelers and others at risk were willing to isolate and keep contacts low. After transmission took off, it was detected early, and was slowed very effectively without strict lockdowns or fines; parks mainly stayed open, people cooperated with health guidelines and Dr Henry’s calm updates showed British Columbians how well we were doing.