Willie O'Dea (Limerick City, Fianna Fail)
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1626. To ask the Minister for Health if he will provide statistics on excess mortality rates in Ireland for each of the years 2019 to 2022; if there is a clear and significant increase in excess mortality, if he intends to initiate an investigation into the causes of these excess deaths; and if he will make a statement on the matter. [1870/23]

Stephen Donnelly (Wicklow, Fianna Fail)
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The Department of Health does not produce estimates of excess mortality. However, the Department closely monitors estimates of excess mortality which are published by a range of different sources.  

Ireland continues to participate in EuroMOMO, a European mortality monitoring activity, aiming to detect and measure excess deaths related to seasonal influenza, pandemics and other public health threats. In addition, the Department of Health and the HSE keep under review a range of population health and epidemiological indicators to assess the impact of health threats in Ireland.

Excess mortality is an epidemiological indicator which can provide information on the burden of mortality.  It compares actual mortality rates, with some baseline for ‘expected’ mortality. Excess mortality can be used to estimate the impact of seasonal influenza, heatwaves, natural disasters, COVID-19 etc. on mortality rates.  Estimates of excess mortality provide an estimate whether deaths were above or below the ‘expected’ level but there may be a number of different factors contributing to this.

There is no single source of data on excess mortality.  A large number of different methodologies have been developed and refined by organisations and academics internationally to attempt to estimate levels of excess mortality.  Work in this field has increased during the COVID-19 pandemic.

Estimation methods vary in relation to, for example, the years used to estimate the baseline, the extent to which demographic change (population growth, ageing etc) is taken into account, the models used for estimation.  Different sources can also report excess mortality using different indicators e.g. as the percentage difference from a ‘baseline’, a z-score, a rate per 100,000 population, a number of excess deaths.  All estimates include caveats on the methodology and some provide estimates within a range.

Given the differences in methodology, the Department of Health monitors and reviews a wide number of different sources for estimates of excess mortality.  It is not therefore possible to provide a single set of statistics on excess mortality.  Below is data from a number of sources which are monitored by the Department:

EuroMOMO

EuroMOMO www.euromomo.eu/ is a European mortality monitoring activity, aiming to detect and measure excess deaths related to seasonal influenza, pandemics and other public health threats.  It has been reporting excess mortality data since 2016.  Official national mortality statistics are provided weekly from the 29 European countries or subnational regions in the EuroMOMO collaborative network.  

The Health Protection Surveillance Centre (HPSC) submits weekly data on behalf of Ireland based on deaths registered with the General Register Office (GRO). The EuroMOMO methodology is explained here www.euromomo.eu/how-it-works/methods/  

EuroMOMO publishes estimates of excess mortality on a weekly basis. Graphs for all participating countries including Ireland are available here www.euromomo.eu/graphs-and-maps EuroMOMO estimates of excess mortality are based on z-scores and indicate if mortality in a week is within the normal range or if there is a ‘substantial increase’ above baseline.

(Chart 1 from Euromomo.eu).  In the period 2019 – 2022, EuroMOMO shows that Ireland experienced a ‘substantial increase’ (that is moderate or high excess mortality) in two periods – during weeks 14-17 2020 and during weeks 2–6 2021.  EuroMOMO estimates that Ireland has not experienced a ‘substantial increase’ in mortality during 2022. During the 2019-2022 period, there were also a number of weeks when mortality in Ireland was below the normal range.

EuroMOMO estimates that a number of European countries did experience high excess mortality during summer 2022 influenced by excessive heat e.g. Spain, Germany, England, Portugal. 

Eurostat

Eurostat publishes monthly estimates of excess mortality for EU countries. This data only incudes estimates from January 2020 onwards and does not include data for 2019.  The purpose is to estimate the impact of the COVID-19 pandemic on mortality in the EU.

Eurostat use the following methodology, ‘The excess mortality indicator simply takes the number of people who died from any cause, in a given period, and compares it with a historical baseline from previous years in a period which was not affected by the pandemic. In this case, the baseline consists of the average number of deaths that occurred in each month during the period 2016-2019’. 

In relation to data for Ireland, it is important to note the following caveat provided by Eurostat, ‘Data from Ireland were not included in the first phase of the excess mortality release: official timely data were not available because deaths in Ireland can be registered up to three months after the date of death. Because of the COVID-19 pandemic, the Central Statistics Office (CSO) of Ireland began to explore experimental ways of obtaining up-to-date mortality data. At the end of April 2021, CSO started publishing a time series from October 2019 until the most recent weeks, using death notices (see CSO website). For the purpose of this release, Eurostat is comparing the new 2020-2021 web-scraped series with a 2016-2019 baseline built using official data. CSO is periodically assessing the quality of these data.’  

Therefore, in the estimates for Ireland the latest monthly data on deaths (from the new web-scaped series (provide by the CSO from rip.ie)) is compared with official mortality data based on death registrations with the GRO for the baseline 2016-2019 period and caution is required in interpreting this indicator.

The latest data is available here ec.europa.eu/eurostat/statistics-explained/index.php?title=Excess_mortality_-_statistics#Excess_mortality_in_the_EU_between_January_2020_and_October_2022

(Chart 2 from Eurostat.eu). Eurostat report excess mortality as the percentage difference between the mortality in a particular month and the baseline (average 2016-2019).  Based on the Eurostat methodology, it is estimated that Ireland experienced excess mortality of 20% or more above baseline in April 2020 and January 2021.  Ireland is estimated to have experienced excess mortality of 10-20% in February 2021, July-November 2021 and May-October 2022.  Ireland is estimated to have experienced mortality below the baseline in 9 of the 34 months between January 2020 and October 2022.

CSO

The CSO has published a number of experimental analyses as part of their ‘Frontier Series’ using data from the website www.RIP.ie as a more-timely source of trends in mortality. These are not official mortality statistics.  The CSO have estimated monthly excess mortality.

The latest release was published on 24 February 2022 examining data to the end of 2021.  ‘Measuring Mortality Using Public Data Sources 2019-2021 (October 2019 - December 2021)’  which is available here www.cso.ie/en/releasesandpublications/fb/b-mpds/measuringmortalityusingpublicdatasources2019-2021october2019-december2021/.The CSO provide a number of methodological caveats to their analysis.

(Chart 3 from Cso.ie). The CSO methodology is based on death notices which appeared on rip.ie.  It compares a 4-year average baseline (2016-2019) with death notices during 2020 and 2021. It estimates excess death notices of 10% or greater in April 2020, January-February 2021 and August-November 2021.  The CSO has not published analysis for 2022.

The Lancet

A study published in The Lancet in April 2022 indicated that excess mortality rates varied substantially in western Europe, with estimated rates in some countries almost as high as those for countries in other global regions.

Ireland was among several European countries (including Iceland, Norway, and Cyprus) which had some of the lowest rates in the world, at less than 50 excess deaths per 100,000 population. Based on the Lancet publication, which does include a number of methodological caveats, Ireland had the third lowest estimated excess mortality rate amongst western European countries for the relevant study period (1 January 2020 to 31 December 2021). www.thelancet.com/article/S0140-6736(21)02796-3/fulltext  

WHO

WHO published (5 May 2022) a report estimating ‘Global excess deaths associated with COVID-19, January 2020 - December 2021’. This report estimated excess mortality associated directly (due to the disease) or indirectly with the COVID-19 pandemic (e.g. due to the pandemic’s impact on health systems and society) between 1 January 2020 and 31 December 2021. The report is available here www.who.int/data/stories/global-excess-deaths-associated-with-covid-19-january-2020-december-2021  

(Chart 4 Department of Health from WHO). The WHO report estimated that Ireland had an excess all-cause mortality rate of 9 (95% confidence interval of -1 to 17) per 100,000 population in 2020 and 50 (95% confidence interval of 40 to 60) per 100,000 population in 2021. The estimated average excess all-cause mortality rate for Ireland 2020-2021 is 29 (range 23 to 36) per 100,000 population. In Ireland the highest excess deaths were recorded in April 2020 and January 2021. Ireland experienced mortality below what would be predicted based on the WHO model during ten of the 24 months of 2020 and 2021.

The WHO report indicated that Ireland appears to have experienced lower excess mortality during the COVID-19 pandemic than many other countries in Europe and globally.

In a follow-up paper by Msemburi et al published in Nature in December 2022 entitled ‘The WHO estimates of excess mortality associated with the COVID-19 pandemic’, the authors note that in general, one can rarely simply look at the excess rate and associated rankings and make statements concerning the manner in which a country dealt with the pandemic, as there are many factors at play. These include: the age structure of the population, the population density and cultural practices, the government responses during different periods of the epidemic, how the population responded to government actions, and the infectiousness and fatality rates of the various variants that were present at different times.

However, these authors analysed WHO mortality data and report a comprehensive and consistent measurement of the impact of the COVID-19 pandemic by estimating excess deaths, by month, for 2020 and 2021. The authors describe a measure known as a P-score. The P-score is defined as the ratio of the excess to the expected deaths, expressed as a percentage. The P-score implicitly considers both the size and the age structure of the population.

This analysis shows Ireland had one of the lowest P-score rates in the EU, with only five other EU/EEA countries having a similar or lower rate. The report also highlights the comprehensiveness of the Irish all-cause mortality data.

There is a very clear national commitment to continue to learn from our experience of the COVID-19 pandemic and to ensure that our public health-led approach evolves as necessary, reflecting national and international evidence and learning.  

A comprehensive evaluation of how the country managed COVID-19 will provide an opportunity to learn lessons from our experiences in dealing with a pandemic. This will help ensure that we are in a better, stronger position if another pandemic or another similar type emergency arrives. It is intended that this will be established in 2023. The Terms of Reference and working arrangements of an evaluation process would be a matter for Government.