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NEW: Reinfection risk of #COVID19 now estimated at 1 in 10,000 cases from latest @Cornell and @WHO study. Details in below thread 
. https://twitter.com/drericding/status/1311049145759694848
. https://twitter.com/drericding/status/1311049145759694848
2) And they did a detail investigation- they literally turned over every rock from 15,808 people with multiple test swabs... and went thru 243 people medical records and did detailed analysis of these potential reinfections and 
to find the 4 new reinfection cases. Hardcore.
to find the 4 new reinfection cases. Hardcore.
3) the 1 in 10,000 average comes from this calculated risk. And more precisely 1 cases from 30,000 person-weeks.
reinfection risk estimated at 0.01% (95% CI: 0.01-0.02%)
incidence rate of reinfection was estimated at 0.36 (95% CI: 0.28-0.47) per 10,000 person-weeks.
reinfection risk estimated at 0.01% (95% CI: 0.01-0.02%)incidence rate of reinfection was estimated at 0.36 (95% CI: 0.28-0.47) per 10,000 person-weeks.
4) overall, they conclude āSARS-CoV-2 reinfection can occur but is a rare phenomenon suggestive of a strong protective immunity against reinfection that lasts *for at least a few months post primary infection*.ā https://www.medrxiv.org/content/10.1101/2020.08.24.20179457v2.full.pdf
