USA – A rambling mind

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.

Pandemic modelling review

Charts 21/22/23/24 with all 4 age groups for scenario UK023 with vaccinations. 17th May 1.8% ,19th July 1% and 1st Sep 2% mean NPI relaxations. v3 transmission k11 = 1, var_eff = 70/85%, fss x1 and fmort x1. Model 800 day outcomes to April 12th 2022 to November 6th. Active, all infected and serious modelled cases

Vaccination has somewhat stabilised the SARS-Cov-2 pandemic in the UK. I summarise the capabilities that I have found necessary and useful in modelling the behaviour of the pandemic; successive variants, different population age-groups, the effect of Government NPIs, and vaccinations.

USA Thanksgiving lessons for UK Christmas and New Year?

Chart 13 model outputs to 425 days, April 1st, 2021, no vaccinations compared with a 3-phase vaccination programme, as at December 8th

We are aware that the rates of cases and deaths in the USA have increased steeply recently, and it seems that the natural public relaxation in precautions against Covid-19 for the Thanksgiving holiday period have exacerbated this. I have run my model with reductions to the USA intervention effectiveness during the Thanksgiving period (reflecting the increase in travel and social interactions in the USA) followed by reintroduction of the intervention effectiveness afterwards, to see the effect on the immediate projections. I have then applied similar changes to my UK models, to anticipate what the possible effect of such relaxations over the UK festive period might be. This is very much a sensitivity test of some scenarios, not a forecast.

Modelling of vaccine strategies

Comparative vaccination charts for the UK to 800 days. Continuation of current NPIs on the left; and an graduated vaccine intervention on the right from January 1st 2021

In my most recent post on November 18th, about updating my Coronavirus model to handle the impact of vaccines, I gave some examples of how case numbers, and more specifically death rates might be improved for the UK through a vaccination programme. Now that there seem to be several vaccines imminent, with efficacies ranging from 70% (Astra-Zeneca/Oxford) through 90% (A-Z/O via a different inoculation regime, and Pfizer), to 95% (Moderna) and several others in the mix, I explore some sensitivities in more detail, and also apply the model to the USA.

Make America well again

Model charts for the USA. Continuation of current policy until a postulated Biden intervention on February 20th 2021, on the left; and an early November 8th intervention on the right

I look at the impact of a postulated change in the timing of further measures to control the Covid-19 epidemic in the USA, against a current background of rapidly increasing daily case numbers and deaths. I also show an updated projection for the UK, both compared with Worldometers forecasts