A rambling mind

Personal Ravings

Peak Serious cases, and the outcomes for Active Cases and deaths in December 2023 plotted against k11

A first 2022 Omicron update

While it is still very early days, both in the New Year of 2022 and also for the Omicron variant, this post adds to my recent 19th December update with a summary of further runs of my model for higher transmissions settings. Last time I ran options up to three times the transmission rate of the Delta variant, and I have now looked at transmission up to five times the Delta rate.

Chart 303 for scenario UK_000 with vaccinations. 17th May 1.8% ,19th July 1%, 1st Sep 2%, mean NPI relaxations and 30th Nov +2% and 10th Dec +3% additional NPIs to reporting date December 18th 2021. v4 transmission k11 = 3, with v4 var_eff = 25/50/70%, fSS=7% and fmort=1.05%. Modelled 1400 day outcomes to December 3rd 2023 including active and serious cases from each variant, and all healthy, infected, cases and deaths.

Omicron modelling update

I have run updates to my model for lower and medium vaccine efficacy to Omicron, and lower, medium and higher virulence and mortality, and continue to compare with reported data. While evidence is still in short supply, nothing has firmly contradicted the impression that Omicron is highly transmissive, as well as being possibly less virulent.

Chart 318 for scenario UK_17 with vaccinations. 17th May 1.8% ,19th July 1%, 1st Sep 2%, mean NPI relaxations and 30th Nov +2% and 10th Dec +3% additional NPIs. v4 transmission k11 = 3, var_eff = 25/50/70%, fSS 7% and fmort 1.05%. Model outcomes to October 29th 2022. Reported active cases and deaths to December 8th. Serious cases for 4 variants.

Just as we thought it was safe to go back into the water

Omicron is feared to have higher infectiousness than the Delta variant, with even greater concerns should it turn out to cause more severe symptoms, higher mortality, and possibly worst of all, if it were able to evade current Covid-19 vaccines. I have made some parametric runs of my model to assess the possible effects.

Case rates are rising in many parts of Europe. https://www.gov.uk/government/collections/slides-and-datasets-to-accompany-coronavirus-press-conferences

The pandemic situation in Europe

The pandemic situation in continental Europe has been worsening rapidly, and I felt that it I should update some country comparisons in a dedicated post.It confirms that the sourcing of data for a Coronavirus model of any given country is a very specific task nowadays, given the considerable differences in the underlying demographics, cultures, Government actions (NPIs) and public responses in the various countries.
This blog post isn’t looking at the modelling per se, but concentrates on the very different outcomes we are seeing across Europe, and looking at some of the reasons why.

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

Pandemic modelling review

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.

Chart 318 for scenario UK079 with vaccinations. 17th May 1.8% ,19th July 1% and 1st Sep 2% mean NPI relaxations. v3 transmission k11 = 1, var_eff = 85/95%, fss x1 and fmort x1. Model 800 day outcomes to April 12th 2022 compared with reported active cases and deaths to October 17th. Serious cases for 3 variants

Booster jab matters

Having just had my 3rd Covid jab, the “booster” jab, it provoked a few thoughts about that, my Coronavirus model, and the wider scene. I had incorporated multiple jabs into my UK model some time ago, and multiple phases for inoculation volumes to cope with the first and second jabs. I am taking this opportunity to report briefly on model outcomes for waning immunity in the context of booster jabs.

Early pandemic Failures of State according to the Sunday Times Insight team

The UK Select Committees’ report into UK Government Covid failures

The UK parliamentary Health and Social Care, and Science and Technology Committees have just jointly published their substantial report criticising the many errors made by UK Government in its handling of the Covid crisis. It praised, justifiably, the excellent strategy (early risk investment) and deployment of vaccines. But its own timing is as questionable as that of any it seeks to criticise.

Solving log(x) = R(x-1) for a family of R values, with R up to 7

Implications of the R0 Reproduction Number in an unconstrained Delta variant environment

In my April 8th 2020 post about the R0 reproduction number and the use of SIR models to model the pandemic, I developed a chart which predicted the proportion of the population uninfected by the end of an unconstrained pandemic.

That chart allowed for an R0 up to 3, but the Delta variant that arrived in the UK a year later, in April 2021, has an R0 far higher than the original, possible 2.5 times as high, as much as R0=7, perhaps.

I have added to the scope of that previous post to develop a chart allowing R0 up to 7..

Repeated elements of the 164-compartment model flowchart with Uninfected, Vaccinated, double Vaccinated, Recovered and Deceased compartments for each group; and Incubation, Sick, Seriously Sick, and Better infective compartments per group, per variant and per vaccination status, with associated transition rates

“Freedom Day”, multiple vaccinations and the Delta variant

In this post, I run a development of my model which includes immunity waning (at a 150 day half-life), vaccine hesitancy by group, multiple vaccine inoculations (representing the typical two jabs required by most vaccines for best immunity) and also the possibility of vaccinated people not only to become infected, but also to pass on the virus even if not infected themselves.

Chart 318 for scenarios UK479 and UK465 with vaccinations and 2021 NPI relaxations up to June 21st with 4% and Aug 16th with 2% NPI effectiveness. v3 transmission k11 = 1, var_eff = 100%, fss and fmort as fort v1 and v2. Modelled 800 day outcomes to April 12th 2022 compared with reported active cases and deaths to June 4th. Serious cases for three variants.

Delta variant impact on June 21st easing – delay or reduce?

Having explored what pandemic advisers might be seeing and highlighting to decision-makers in Government, I run scenarios with different settings for the planned June 21st relaxation of lockdown, the last in the series of relaxations over the first half of 2021, following the January 3rd lockdown. These model scenarios show examples of what the relative consequences of the June 21st relaxation as planned, versus four other options:- cancellation of the June 21st step altogether, two different delays, of 28 and 56 days, and lastly a 50% reduction in the scope of the June 21st relaxation.

Loading…

Something went wrong. Please refresh the page and/or try again.


Follow My Blog

Get new content delivered directly to your inbox.

%d bloggers like this: