Publication - Research and analysis

Coronavirus (COVID-19): modelling the epidemic (issue no. 72)

Latest findings in modelling the COVID-19 epidemic in Scotland, both in terms of the spread of the disease through the population (epidemiological modelling) and of the demands it will place on the system, for example in terms of health care requirement.

Coronavirus (COVID-19): modelling the epidemic (issue no. 72)


1. On 16 September 2021, daily data on new cases and tests were not refreshed due to a technical issue affecting the availability of the data.

2. Using data to 4th October 2021.

3. Particular care should be taken when interpreting this estimate as it is based on low numbers of cases, hospitalisations, or deaths and / or dominated by clustered outbreaks. It should not be treated as robust enough to inform policy decisions alone.

4. The cyan bars use Covid-19 test data and purple bars use multiple sources of data. The estimates produced by the Scottish Government are the two on the left. (Yellow uses confirmed cases from PHS and deaths from NRS; green uses wastewater data).The UKHSA consensus range is the right‑most (red). Data to 4th October. R, incidence and growth rate as of 21st September.


6. A serious Covid-19 event includes hospital admissions or deaths due to Covid-19.

7. All scenarios are based on current vaccine roll-out plans and efficacy assumptions. Data to 4th October.

8. The actual positive tests are adjusted to coincide with the estimated day of infection.

9. Actual data does not include full numbers of CPAP. ICU bed actuals include all ICU patients being treated for Covid-19 including those over 28 days.

10. Three week projections are provided here: Scientific evidence supporting the government response to coronavirus (COVID-19) - GOV.UK (

11. The exceptions are Na h-Eileanan Siar, Orkney Islands and Shetland Islands.

12. Values are included in Table 1 in the Technical Annex.

13. Anomalously high values, one in Seafield (Edinburgh) in mid-February (see Issue 40), one in Dunblane in mid-June, and two in Daldowie in January, were removed. For this graph, a wastewater RNA average using the last 7 days of data is computed at every sampling date.

14. Advancements in detection and interpretation practices allow us to identify when outlying results are anomalous rather than indicators of spikes in Covid-19 levels. Table 2 provides population weighted daily averages for normalised WW Covid-19 levels both with and without the outliers removed. See Technical Annex in Issue 60 of these Research Findings for further details.

15. Coverage as at the week beginning 28th September 2021, when outliers are excluded.