Thread by @MartinJuhl2

Compilation on recent assessments from various sources using different models to provide an early estimates on relative and current reproductive number & transmissibility of the new B.1.1.7 Variant of Concern
1/x

@Peter_R_Hansen B.1.1.7 relative reproductive number ≈ 1.43 times larger. (generation time 4.7) thus 43% more infectious

Estimation for 1 day = 1.08 [CI 1.07-1.09] (8% pr day)

Estimation for 7 days 1.71
2/x

https://twitter.com/Peter_R_Hansen/status/1353808634652708864?s=20

@SSI_dk @henrik_ullum
Cluster B.1.1.7 is clearly more contagious:
Increased relative reproductive number
SSI 1.2-1.5
3/x

https://twitter.com/henrik_ullum/status/1352659909582729218?s=20

London School of Hygiene and Tropical Medicine:
(UK generation time = 6.5 days)

VOC 202012/01 is 56% more transmissible (95% credible interval across three regions 50-74%) than preexisting variants of SARS-CoV-2
4/x
cmmid.github.io/topics/covid19…

NERVTAG meeting on SARS-CoV-2 variant under investigation VUI-202012/01 (UK generation time = 6.5 days)
Growth rate from genomic data: which suggest a growth rate of VUI-202012/01 that
that is 71% (95%CI: 67%-75%) higher than other variants.
5/x
khub.net/documents/1359…

Public Health England

Figure shows the mean ratio of growth factors (corrected by power of 6.5/7 to give reproduction number scale) = 1.47 (95% CI: 1.34-1.59).

6/x
assets.publishing.service.gov.uk/government/upl…

Lars Risbo analysis part 1
Relative R factor estimated at 1.45 (generation time 4.7 days), equals to ~8% daily relative growth rate facebook.com/groups/2450225…
7/x

Lars Risbo analysis part 2
Simple exponential trendline showing ~79% growth per week (exp(0.582)=1.79). Adjusted to a generation time of 4.7d: Rrel=exp(0.582/7*4.7)=1.49
Probably several caveats, but do not anticipate increased contact tracing for B.1.1.7 playing a large role
8/x

It is very important what percentage B.1.1.7 growths with per day/week, as things can quickly spin out of control again, as it did in October/November/December

https://twitter.com/MartinJuhl2/status/1339682767316115459?s=20

9/x

Good to see that @Heunicke is taking it seriously

SSI = Rt(B.1.1.7) = 1.07 (95% CI [0.83 ; 1.32]) (Kontakttallet)
ssi.dk/-/media/cdn/fi…

10/x
dr.dk/nyheder/politi…

Updated analysis by @Peter_R_Hansen using recent data from Danish CDC (SSI)
11/x

https://twitter.com/peter_r_hansen/status/1354866358513614848

Further analysis and some preliminary future predictions
12/x

https://twitter.com/peter_r_hansen/status/1355284729335930880