UK Covid Modelling
As of 30th March 2023
Current Covid-19 status in the UK: R = 0.91
(number of hospital cases: dropping slowly)
As part of our approach to testing our simulation skills within the company (and part of a service we provide to outside agencies), we apply our FluidFlowEngine tool to everyday concerns, from public health, to renewable energy sources and transport simulation.
Dynamic modelling comes in many forms, and testing your abilities in a real-world context is a key part of what we try to do.
Here, for example, is our ongoing calculation of R (the reproductive number of COVID-19) in England, since March 2020:
Estimated R in England
When R is below 1.0, then a pandemic is under control. When R is above 1.0 then the epidemic is spreading.
The following graph is the result of a real-time R number calculation in England during the 2020-23 coronavirus pandemic.
The latest UK government SAGE (Scientific Advisory Group for Emergencies) figure should be available here, so you can make your own assessment as to the accuracy of our model. *The UK Government has informed us that it will officially cease updating that page in December 2022, however we will continue to provide this service in 2023.
For the last seven days that data was available, the R number in England was calculated to be:
21 Mar 0.98
22 Mar 1.00
23 Mar 0.97
24 Mar 0.95
25 Mar 0.93
26 Mar 0.90
27 Mar 0.91
The historical R number data since 1 April 2020 can be downloaded here
*** Whereas the "Delta" variant of COVID-19 was largely being spread through the unvaccinated population, the "Omicron" variant can also spread through those who have had two or three jabs already (particularly if the first two were Astra-Zeneca injections, with the last more than six months ago). It is entirely possible to be infected twice with Omicron and previous infection with Alpha, Beta or Delta offer no immunity against infection with the latest Omicron strain, which is the most prevalent COVID strain in the UK in the winter of 2022/23. Please be careful out there. This has not gone away and if a new variant emerges in the next six months, we could still be in very tricky position. ***
A booster jab has been developed which should provide enhanced immunity to Omicron BA.5. If you have access to this booster jab (over 50's in the UK and those with vulnerable conditions or in particular industries), please take that up immediately.
To protect yourself and those around you, please keep fully vaccinated (and be prepared for a regular, variant-specific booster jab, prior to every winter season for the next few years).
A few pieces of data:
1st Wave of the COVID-19 pandemic (Feb-Apr 2020):
The Covid-19 pandemic arrived in the UK sometime before February 2020.
The end of the 1st Wave and the first UK National Lockdown:
England entered its first National Lockdown on 23rd March 2020.
England had an R less than 1.0 between 11th April and 8th August 2020.
The lowest R that England went down to during the 2020 summer lockdown was 0.64 in July 2020.
2nd Wave of the COVID-19 pandemic (Sep 2020-Jan 2021):
It was clear (with > 95% probability) that the pandemic was accelerating again on 5th September 2020.
This signalled the emergence of a second, severe Covid-19 wave in the UK.
However, the UK Government didn't lockdown again until 5 November 2020.
The peak R in England during the second wave (in September 2020) was 1.88.
The R in England dropped below 1.0 for a second time on 20 November 2020.
The lowest R that England went down to during the second lockdown was 0.86 in November 2020.
And rose back above 1.0 again on 5th December 2020.
On 3rd January 2021 it was clear that the pandemic was accelerating again, and a third National Lockdown was required. The UK Government announced a new National lockdown on 4th January 2021, to start immediately on 5th January.
The peak R in England during the latter part of the second wave (in January 2021) was 1.39.
The R in England dropped below 1.0 for a third time on 18th January 2021 and remained below 1.0 until 19th May 2021.
The lowest R that England saw in 2021 was 0.69 on 5th March 2021.
3rd Wave of the COVID-19 pandemic (May 2021-present day):
In England, we are currently experiencing a prolonged third wave due to the Delta variant and now, the Omicron variant of the virus. There have been at least seven peaks in virus transmission in the UK since May 2021.
The lowest R that England saw in 2022 was 0.71 on 3rd November 2022.
For the unvaccinated, the Omicron variant is still dangerous. You are 20 times more likely to be in a hospital ICU with Omicron if you are unvaccinated, than if you have had 3 jabs. Omicron is only 11% less deadly than Delta for the unvaccinated individual. The difference is that with a booster jab, you are much less likely to require hospitalisation. Reports will indicate that Omicron is less serious, but that is entirely because the majority of potentially vulnerable individuals are treble jabbed and therefore the illness is likely to be milder for them (in general). Having had Covid-19 in the past does not prevent you catching it again, and long Covid is still a significant concern.
We recommend you limit your time in large crowds of strangers in enclosed indoor spaces without ventilation (and offices and schools should introduce CO2 monitors as a matter of routine, restricting entry should CO2 levels rise
above a nationally mandated figure). For the individual, we recommend you get a fourth (booster) injection when it becomes available in the UK (expected to be October-November 2022).
Please remember, meeting people outside has always been generally fine: Covid-19 is an airborne disease who's severity depends on the amount of virus you breathe in. Covid-19 builds up gradually in an enclosed space, and good ventilation is key.
As you might expect, we routinely model aerosol and droplet transmission, and are involved with a very detailed project comparing closed-room and open, ventilated environments. Those results are provided for academic and Government use, and published separately
If you need any further information, please contact firstname.lastname@example.org