During the coronavirus pandemic, the Continuous Mortality Investigation (CMI) is publishing frequent UK mortality analysis through its mortality monitor. The latest update covers weeks 33 to 36 of 2020 (8 August to 4 September) based on provisional England & Wales deaths data published by the Office for National Statistics (ONS) on 15 September 2020.
The key points of this update are:
- There were nearly 700 more deaths registered in weeks 33 and 34 (combined) than if death rates had been the same as corresponding weeks of 2019. This is likely to be due to the heatwave from August 7 to 12.
- The August bank holiday was in week 35 of 2019, but in week 36 of 2020. This leads to excess mortality being artificially high in week 35 and artificially low in week 36, so it is not helpful to consider these weeks in isolation.
- Considering weeks 33 to 36 together, there were 2% fewer deaths registered than if death rates had been the same as corresponding weeks of 2019. In the previous four-week period, weeks 29 to 32, deaths were 4% lower than expected.
- There have been around 60,600 more deaths in the UK from the start of the pandemic to 4 September 2020 than if mortality rates were similar to those experienced in 2019. This is a decrease of around 4,000 from the peak at 12 June 2020.
Cobus Daneel, Chair of the CMI Mortality Projections Committee said: “Deaths in August remained close to normal levels. We will continue to closely monitor the figures, particularly given recent increases in coronavirus cases and hospitalisations.”
All mortality monitor weekly updates are publicly available on the mortality monitor page.
“Excess” deaths are the difference between actual deaths in 2020, and those that we would expect if mortality rates had been the same as in 2019. The ONS weekly deaths figures are for registered deaths, for weeks ending on a Friday. We tend to see fewer registered deaths in weeks containing a bank holiday, when register offices are not typically open.
The August bank holiday was in week 35 of 2019, but in week 36 of 2020. This means that an unadjusted comparison between those weeks in 2019 and 2020 would be misleading.
The cumulative number of excess deaths as at 4 September is lower than the number as at 12 June because there have been fewer deaths than expected during the past seven weeks of data; i.e. excess deaths have been negative in those weeks.
The CMI intends to publish its next mortality monitor for week 39 on 6 October 2020. This will coincide with the publication of the regular quarterly mortality monitor, for Q3 of 2020.