Read on Twitter
Data from @GovCanHealth which was obtained by @kellygrant1 at @globeandmail with some astonishing stats on effectiveness of the vaccines, even after a single dose. The calculations behind these numbers are here: https://twitter.com/KashPrime/status/1389440791362383874?s=20
This matches roughly with similar stats published by Ontario Public Health. You can download it here: https://www.publichealthontario.ca/-/media/documents/ncov/epi/covid-19-epi-confirmed-cases-post-vaccination.pdf?la=en
Also discussed here: https://twitter.com/zchagla/status/1390006277896540161?s=20
Also discussed here: https://twitter.com/zchagla/status/1390006277896540161?s=20
Much discussion about the new study from Qatar showing the second dose is more effective, but our situations are not comparable. They stuck to the 3w schedule, so could not study how immunity evolves after more time. https://www.cp24.com/news/early-efficacy-of-first-pfizer-covid-19-shot-in-new-study-doesn-t-disprove-canada-s-dosing-strategy-author-1.5416538
PHO's data shows that cases drop, and immunity increases significantly 2-4w after vaccination with one dose, something the Qatari study would not have seen since they vaccinate everyone at 3w.
It also shows, like PHACs numbers, significant breakthrough infections and deaths in those >80. These are brought to zero with a second dose. We need to prioritize this population for a second dose.
In short, these vaccines are incredibly effective, far better than we could have ever hoped. Hopefully all of you will get the chance to get one in the next few weeks!
