This is good news, but Brits may be reading too much into it. I've been eyebleeding it and the impact seems pronounced after the 2nd dose, (looking at the 40-60 age group), but it's confusing because of the lockdown and also compensating for the lag in vaccination/hospitalisation https://twitter.com/segal_eran/status/1356313705684869121

It's nowhere near some of the fantasy figures I see bandied around on Twitter for what we should expect from the UK's vaccination program...but cases in the 40-60s have flatlined, which doesn't look like the vaccine is having much impact, with 40% first dose 10% 2nd dose on 17/01

17/01 is the sweet spot for Over 60s. The majority have had one dose, 2 weeks prior, and the lockdown is 10 days in and having an effect...but cases are only flatlining at that point, then 2nd doses ramp up and cases start dropping off, with hospitalisation following a week later

Looks like a combination of 1 dose and lockdown stabilises it, but only when the 2nd dose starts ramping up that the effect become visible

Cases drop within days and then hospitalisations drop 7-10 days after

Certainly doesn't give me much confidence in UK's 1 dose strategy

For clarity:

The assumption is that the vaccination takes 14 days for the first dose to work, so case/hospitalisation data we see for 31/01 would be a result of vaccination on 17/01

It *might* be that efficacy keeps increasing after 21 days, but it's not something I'd gamble on