We have published a new report on our real-time tracking of COVID-19.

We have highlighted the key updates and provided interpretation of what these updates mean. The lead researchers have also given their headline comment.

Updated findings

1. The estimated number of new daily infections on the 3rd December across England is 54,400 (47,100–63,100, 95% credible interval). The daily infection rate is estimated to be 97 per 100k population per day nationally. The highest rate remains in the North East (NE) with 149 infections per 100K population followed by London (GL) at 146. These rates correspond to 3,950 and 13,000 daily infections, respectively. There is then a drop to the South East (SE) (104) and the South West (101). In most of the remaining regions rates are around 80 per 100K population (East Midlands (EM), East of England (EE), Yorkshire and the Humber (YH) and West Midlands (WM)). The lowest infection levels are in the North West (NW) with approx. 46 per 100k. Note that a substantial proportion of these infections will be asymptomatic.
2. The daily number of deaths has been declining, but it is now slowing to a plateau such that we forecast between 94 and 161 deaths per day by the 24th of December, a very slight downward revision of what we predicted last week.
3. This week we believe the national Rt to be very close to 1, mostly due to an estimated Rt of 1.14 in GL, where there is a 98% probability of a growing epidemic. This probability is reasonably high in both the NE and SE (52% and 39% respectively). For everywhere else, the chance of Rt being above 1 is around 15% or less.
4. The growth rate for England is 0.00 (-0.01– 0.00) per day. This means that, nationally, the number of infections is flat, corresponding to an Rt of around 0.95, consistent with last week’s results.
5. Our estimates for the attack rate, that is the proportion of the regional populations who have ever been infected, have NE at 51% and GL at 49%. WM, EM and NW are all also above the national average with 45%, 42% and 42% respectively. The SE and SW continue to have the lowest attack rates at 32% and 31%. These constitute a major downward revision of last week’s estimates.
6. Note that the deaths data used are only very weakly informative on Rt over the last two weeks. Therefore, the estimate for current incidence, Rt and the forecast of daily numbers of deaths are likely to be subject to some revision.

Interpretation

Our estimates show a pandemic with Rt values estimated mainly very close to 1. This is reflected in infection incidence which has remained reasonably constant for over one month and is now starting to feed through to the deaths, which are hitting a plateau.

Our change to the vaccine efficacy assumptions has resulted in a downward revision of infection attack rates. Whereas previously we were estimating 81% and 69% for the 5-14 and 15-24 year-olds respectively, these have been revised down by around 10% to 70% and 59% respectively.

Plots of the IFR over time show that we are currently estimating a decreasing IFR in all age groups with the most steep fall in the younger age groups. Following this drop, the overall IFR is 0.24% (0.23%–0.26%), highest in the over-75s at 3.4% (3.1%–3.7%), similar to that estimated last week.

For context, in addition to the data used here, the number of reported new positive cases (by date of specimen) is increasing. As a caveat to this, trends in the number of reported cases are highly dependent on the volume and targeting of testing, the public’s testing behaviour and significant reporting delays, and therefore are difficult to interpret. Overall, there have now been 9.0million positive tests in England, which we estimate to have been generated from 22.7million cumulative infections. This would suggest that almost 40% of infections have been identified. This seems plausible if a little high considering the low ascertainment rates of the first wave. In contrast to the cases, the admissions to hospitals have been falling in number, though there is now evidence that this is flattening out. The prevalence of infection, as estimated by the ONS Coronavirus Infection Survey, remains stable around 1.65% in England, while showing some slight increasing trends in some regions. As yet, infection with the omicron variant is not sufficiently widespread to greatly influence these results. It is anticipated that this will not be the case for much longer.

Comment from lead researchers, Prof Daniela De Angelis & Dr Paul Birrell

We estimate a stable national epidemic, with an overall infection rate now at around 97 per 100,000 population.  Prevalence of COVID19 remains high, and the number of deaths is plateauing. There is no sign in the data used here of the new Omicron variant, which currently is only slightly affecting the number of positive cases. It will probably take some time before infections with Omicron appear in the ONS CIS data and, if at all, in the deaths. As usual we will monitor the situation closely.”

Read full report: https://www.mrc-bsu.cam.ac.uk/now-casting/nowcasting-and-forecasting-9th-december-2021/