More than a million Australians who contracted Long COVID at the height of the pandemic cost the economy almost $10 billion in lost productivity.

Researchers from the Australian National University (ANU), the University of NSW (UNSW) and the University of Melbourne have found that around 100 million working hours were lost in 2022 because affected adults were unable to work or reduced their working hours.

It is estimated that up to 1.3 million Australians were living with Long COVID at the time, the study found.

“We estimate this equates to economy-wide losses averaging about $9.6 billion in 2022, or a quarter of Australia’s real gross domestic product growth this year,” ANU Professor Quentin Grafton, one of the study’s authors, said on Monday.

“Our research likely underestimates the economic impact of Long COVID because it does not take into account losses such as healthy employees who are unable to work because they are caring for others with Long COVID.”

Most of the affected workers were between 30 and 49 years old.

Valentina Costantino of UNSW’s Kirby Institute said the study showed MPs needed to place more emphasis on tackling Long COVID.

More than four years after COVID-19 first appeared in the country, up to 873,000 Australians were likely still living with the disease, Dr Costantino said.

“A major focus of COVID-19 health policy is on preventing hospitalizations and deaths from acute COVID-19, with less attention paid to long COVID,” she said.

Another author of the study, Raina MacIntyre, said strategies to contain COVID-19, and therefore Long COVID, should focus on indoor air quality and improved ventilation.

“Financial support for long-Covid patients, at least for those who are unable to work due to their symptoms, such as access to a disability pension, would reduce their economic burden,” said Professor MacIntyre of UNSW.

“Long COVID” refers to long-term symptoms such as fatigue, shortness of breath and joint pain that some people experience after having COVID-19.

In June, the federal government announced $14.5 million in grants, part of a total of $50 million to improve understanding of strategies for managing long COVID in the population.