The Covid-19 pandemic reduced life expectancy in 2020 by the largest amount since World War II, according to a study published by Oxford University, with the life expectancy of American men dropping by more than two years.

Life expectancy fell by more than six months compared with 2019 in 22 of the 29 countries analysed in the study, which spanned Europe, the US and Chile. There were reductions in life expectancy in 27 of the 29 countries overall.

The university said most life expectancy reductions across different countries could be linked to official Covid-19 deaths. There have been nearly 5 million reported deaths caused by the new coronavirus so far, a Reuters tally shows.

"The fact that our results highlight such a large impact that is directly attributable to Covid-19 shows how devastating a shock it has been for many countries," said Dr Ridhi Kashyap, co-lead author of the paper, published in the International Journal of Epidemiology.

There were greater drops in life expectancy for men than women in most countries, with the largest decline in American men, who saw life expectancy drop by 2.2 years relative to 2019.

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