The future of excess mortality after COVID-19

Four years on from the outbreak of the pandemic in 2020, many countries worldwide still report elevated deaths in their populations. This impact appears generally independent of healthcare systems and population health. This trend is evident even after accounting for shifting population sizes, and the range of reporting mechanisms and death classifications that make inter-country comparisons complex. There is also likely a degree of excess mortality under-reporting.

Quantifying excess mortality has been an acute challenge since 2020 due to the exceptional mortality rates of the pandemic. Excess mortality refers to the number of deaths over and above an assumed “expected” number of deaths. The different methods of estimating expected mortality can generate very different excess mortality rates.

This represents a potential challenge for Life and Health (L&H) insurance, with potentially several years of elevated mortality claims ahead, depending on how general population trends translate into the insured population. Ongoing excess mortality can have implications for L&H insurance claims and reserves. Excess mortality that continues to exceed current expectations may affect the long-term performance of in-force life portfolios as well as the pricing of new life policies.

In this research Swiss Re Institute projects excess mortality in the US and UK over the next 10 years under different scenarios, by analysing excess mortality trends globally and disaggregating the underlying factors driving them. We find that excess mortality persists today and may potentially continue for the next decade. Our general population forecasts suggest that excess mortality will gradually tail off by 2033, to 0–3% in the US and 0–2.5% in the UK. In comparison, by our calculation excess mortality in 2023 was in the range of 3–7% for the US, and 5–8% in the UK.

Under an optimistic scenario, we find that US and UK pandemic-linked excess mortality would disappear by 2028, reverting to pre-pandemic mortality expectations. Under a pessimistic scenario, we expect excess mortality to remain elevated until 2033, above pre-pandemic expectations. The ranges allow for varying mortality improvement assumptions – used to calculate the expected level of mortality – and differing data quality and reporting methods. Our estimates use our chosen approach for the mortality improvement assumption and so may differ from those reported by other institutions.

We developed a standardised methodology for cross-country comparison of pandemic-era excess mortality. This shows four key patterns: in the US, excess mortality peaked early and declined rapidly. In contrast, the UK’s early peak was followed by a slower decline. Australia delayed its peak by close to two years and achieved a quick decline. Canada reported very low excess mortality in 2020, with a gradual increase peaking in 2022 and 2023, reflecting a late peak and slow decline. These patterns correlate with countries’ responses to COVID-19, specifically the timing and effectiveness of preventive measures and the rate at which mortality returned to expected levels.

The pandemic has significantly altered the causes of excess deaths. We analysed the evolution of major causes of death from 2020 in developed countries that report such data. Respiratory mortality accounts for the largest share of excess deaths each year since 2020, as expected. However, we find evidence of inconsistency in the causes of death recorded over this period, with signs that other causes of death were misclassified as COVID-19. The UK and US data shows a large, unexplained jump in deaths attributed to cardiovascular disease (CVD) since 2020. Some countries also reported excess mortality over a pre-pandemic baseline for other major causes of death, such as cancer.

Based on current medical trends and expected advancements, we conclude that COVID-19 is still driving excess mortality both directly and indirectly. In the long term, lifestyle factors that contribute to poor metabolic health and lead to obesity and diabetes may become another compounding factor in population excess mortality. Insurers may wish to continue to monitor excess mortality and its underlying drivers in the general population closely, as well as the differences between general and insured populations.