LONDON, Nov. 10 (Xinhua) -- The number of working-age adults in the UK who are currently unemployed has increased by half a million since 2019, the latest data from the Office for National Statistics (ONS) shows. This has mainly been caused by the onset of the COVID-19 pandemic in 2020.

Around 2.5 million people were economically inactive due to long-term sickness in the summer of 2022, compared to around two million people in the spring of 2019, said the ONS on Thursday.

An ONS spokesperson told Xinhua that this was the highest rate of inactivity among the long-term sick since records began in 1993. "It was generally falling, from shortly before the turn of the millennium, but started to rise again in 2019, and has now gone past its late 90s peak."

Among the half a million more people who are economically inactive due to ill health, 363,000 have left the workforce since the onset of the pandemic in early 2020.

Hugh Stickland, ONS senior statistician, said: "The largest increase came from people with 'other health problems or disabilities'. While this category includes people affected by long COVID, we think that's only one of several contributing factors. The next highest rise was among people with back or neck problems; it's possible that increased home working has given rise to these kinds of conditions."

The number of people reporting mental illness and nervous disorders as their main health condition has also risen by 22 percent in the past three years, with the sharpest increases seen after 2020, according to the ONS.

"While symptoms of long COVID may not be the only contributor to increased long-term sickness in the working-age population, the pandemic's wider impact on health is still likely to be an important factor in increased long-term sickness," said the ONS report.

The study showed that while older people still make up the majority of workers inactive due to long-term sickness, the sharpest relative increases in recent years have been among men and women aged between 25 and 34.

This group made up 11 percent of those inactive due to long-term sickness in April to June 2019, but the percentage rose to 14 percent in the same period in 2022.

"The rise for this age group has been more pronounced since the start of the pandemic," said the ONS.