Office for National Statistics

The Kraken Wakes*

Chart 318 for scenario UK_1246 with adult vaccinations, and vacs for 5-11 year-olds from April 1st 2022. 24th February NPI reduction = -79.64%. Omicron BA.1 transmission k11 = 6, BA.2 k11 = 8, BA.4-5 transmission k11=11, Kraken XBB.1.5 transmission k11=15. All k2hl = 5.1. Omicron BA.1 var_eff = 25/50/70%. Omicron BA.2 var_eff = 70/85/95%. Omicron BA.4/5 var_eff = 25/50/70%. Kraken XBB.1.5 var_eff = 25/50/70%. Omicron BA.1 fSS=3% and fMORT=1.5%. Omicron BA.2 and BA.4-5 fSS=3% and fMORT=1.5%. Kraken XBB.1.5 fSS=3% and fMORT=1.5%. Model outcomes to December 3rd 2023. Reported active cases and deaths to 7th Feb 2023. Serious cases for 7 variants.

I have continued to improve and run my Coronavirus model daily. The code for the model is now at version 172, and I have added a dataset to represent the variant XBB.1.5, known informally as “Kraken”. The fit of the model to reported deaths is good. I explore in the article the behaviour of Modelled vs. Reported Active Cases.

Declining Omicron cases but increasing deaths

The WHO estimates of Covid worldwide officially reported deaths vs. actual excess deaths from the pandemic

Something odd seems to be happening with the relationship between reported UK Covid-19 cases and deaths in the last few weeks, when deaths have been increasing somewhat more quickly than recently, but cases have declined steeply. My model charts seem to expose this oddity.

Model update following UK revision of Covid-19 deaths reporting

Model forecast for the UK deaths as at August 14th, compared with reported for 84.3% lockdown effectiveness, on March 23rd, modified in 5 steps by -.3%, -0% -0% and -0% successively

On August 12th, the UK Government revised their counting methodology and reporting of deaths from Covid-19, bringing Public Health England’s reporting into line with that from the other home countries, Wales, Northern Ireland and Scotland. I have re-calibrated and re-forecast my model to adapt to this new basis.

The effect of lockdown easing in the UK

My forecast for the UK deaths as at July 30th, including trend line for reported deaths, for 83.5% lockdown effectiveness

As reported in my previous post, there has been a gradual reduction in the rate of decline of cases and deaths in the UK relative to my model forecasts. This decline had already been noted, as I reported before, by The Office for National Statistics and their research partners, the University of Oxford, and reported on the ONS website.
I had adjusted the original lockdown effectiveness in my model (from 23rd March) to reflect this emerging change, but as the model had been predicting correct behaviour up until mid to late May, I will present here the original model forecasts compared to the current reported deaths trend.