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Today I wrote about why the new COVID-19 variants are such a threat, and will make exponential growth that much worse:
(Paywalled) https://www.qpbriefing.com/2021/01/29/increased-variant-transmissibility-poses-an-exponential-threat-health-experts/
(Paywalled) https://www.qpbriefing.com/2021/01/29/increased-variant-transmissibility-poses-an-exponential-threat-health-experts/
Two hypothetical scenarios were laid out by @imgrund that help illustrate the difference between the strains:
Scenario A: 1,000 daily cases of the "normal" variant, at a reproductive value of 0.9, would turn into 500 daily cases after one month.
Scenario A: 1,000 daily cases of the "normal" variant, at a reproductive value of 0.9, would turn into 500 daily cases after one month.
But the variants have higher transmissibility, which raises their reproductive value (R0) by about 0.4. That's *a lot* because it's an exponential function, and thus very sensitive.
Add 0.4 to 0.9 for Scenario B, and if you started with 1,000 daily U.K. variant cases then all else being equal with an R0 of 1.3 you'd have 10,000 daily cases after one month.
And that rapid growth makes it *really* difficult to respond in time with public health interventions
And that rapid growth makes it *really* difficult to respond in time with public health interventions
Yesterday Dr. Adalsteinn Brown, when unveiling Ontario's modelling data, opened the door to schools being re-opened for in-person class. But there was a very important caveat.
Brown said that Ontario would have to continue to see declining cases, and would need an equivalent of a "normal" reproductive value of 0.7 or below given the high transmissibility of the variants.
Ontario has never achieved that low of an R0 during the pandemic.
Ontario has never achieved that low of an R0 during the pandemic.
There are other issues too — young people are potentially more susceptible to the variants, which experts say could complicate school re-opening — but regardless the variants are very serious.
My colleague @snehduggal reported the government's plan to respond to the variants, including increased border controls, which subscribers can read here: https://www.qpbriefing.com/2021/01/29/mandatory-testing-at-pearson-to-serve-as-a-stopgap-until-new-federal-travel-restrictions-kick-in-says-premier-ford/
