Thread by @MichaelSFuhrer

10 days ago it was conceivable that NSW could control delta and reach low covid (by int'l standards) well before 80% vax, safely open and reduce covid simultaneously.

Now appears that NSW will barely control covid, at high caseloads (~500/Mpop/day) when reaching 80% vax.
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Lines on the graph are extrapolations from 9, 14, and 20 August. In 11 days the extrapolated date of effective* 80% vax of 16+ has moved forward 15 days, and the date of achieving R=1 through vax has moved backwards by 22 days. Separation has gone from 6 weeks to 4 days.
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This is a result of the higher observed R, which seems robust.

Likely scenario: NSW will achieve 80% vax of 16+ in October after 3.5 months lockdown, with cases in several 1,000s/day. Pressure to remove lockdown will be intense.
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I don't meant to paint this as a doom scenario. NSW population will be highly vaxxed, IFR will be low. Lockdown will have saved lives by buying time for vax.

But, comparisons to UK, Israel which seemed hyperbolic 11 days ago are realistic now. Need to adjust expectations.
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11 days ago it seemed hyperbolic to consider an NSW open to international travel while other states kept borders closed to NSW. Now it seems plausible - NSW will be a hotspot even by world standards, and other states lagging in vax.
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*effective 80% vax of 16+ means 160 doses per 100 16+ pop.

I assume very simple linear extrapolation of vax, each dose 40% effective against transmission immediately. Ignore reduction in S due to infection. More complex model from @Chrisbilbo comes to same conclusions.
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