Life expectancy in western Europe bounced back in 2021 after the shock of 2020, a new study has found.

But it’s continuing to drop in the US, Chile and eastern European countries, with lower COVID-19 vaccination rates.

Researchers looked at life expectancy data from 29 countries between 2015 and 2021, covering the five years before the pandemic and two in it. 

In France, Belgium, Switzerland and Sweden, life expectancy has returned to pre-pandemic levels, while other western European nations have enjoyed a partial restoration. 

But life expectancy has continued dropping in the US, Chile and eastern Europe (except Slovenia, which partially bounced back), according to the paper, published this week in Nature Human Behaviour.

Reduced life expectancy was correlated with lower vaccination uptake, the study found. 

While COVID-19 is typically more dangerous the older you are, in 2021 the “the age profile of excess mortality…was younger, with those in under-80 age groups contributing more to life expectancy losses”. This was partly attributed to lower vaccine uptake amongst the middle-aged compared to elderly, particularly in the US.

“This means that older age groups were better protected during the large Delta wave in the United States in the summer/autumn of 2021 than during previous waves.”

Working age Americans are also more likely to be obese than their European counterparts – weight being another risk factor for COVID-19.

While life expectancy in Denmark, Finland and Norway didn’t increase as expected before the pandemic, it didn’t fall either – fast vaccine rollouts, “effective non-pharmaceutical public health interventions and high baseline capacities of the health care systems” being credited. 

While Sweden’s life expectancy recovered to pre-pandemic levels in 2021, this came after “substantial [life expectancy] loss in 2020” and “elevated mortality” in 2020 which “cannot be regained. The Scandinavian nation adopted a much less restrictive approach to handling COVID-19 than its neighbours in 2020, experiencing much more death and illness as a result

Australia and New Zealand did not experience any drop in life expectancy through 2020 and 2021, the researchers noted. Both countries adopted a strict zero-tolerance policy for the virus through much of those two years, before easing up on restrictions in 2022 after their vaccination rollouts. 

“While COVID-19 has been the most severe global mortality shock since World War II, we will have to wait to know whether and how longer-term [life expectancy] trends are altered by the pandemic,” the researchers concluded.

“Extrapolating our findings from 2021, it is plausible that countries with ineffective public health responses will see a protracted health crisis induced by the pandemic, with medium-term stalls in [life expectancy] improvements, while other regions manage a smoother recovery to return to pre-pandemic trends.”

The split between west and east could make it harder for the EU to achieve its goal of minimising differences in life expectancy across the bloc, the researchers said.