The World Health Organization (WHO) estimates 10-20% of people suffer from long COVID after they recover from the initial COVID infection.
Authors
C Raina MacIntyre
Professor of Global Biosecurity, NHMRC L3 Research Fellow, Head, Biosecurity Program, Kirby Institute, UNSW Sydney
Long Chu
Associate Professor, Crawford School of Public Policy, Australian National University
Quentin Grafton
Australian Laureate Professor, Crawford School of Public Policy, Australian National University
Tom Kompas
Professor of Environmental Economics and Biosecurity, The University of Melbourne
Valentina Costantino
Research Associate, Biosecurity Program, Kirby Institute, UNSW Sydney
Common symptoms include fatigue, shortness of breath and "brain fog", but more than 200 different symptoms have been linked to long COVID. The condition affects daily functioning and can be debilitating.
Our research, published today, estimated the economic burden of long COVID in Australia. We calculated long COVID cost the Australian economy almost A$10 billion in 2022 alone.
What is long COVID?
The WHO defines long COVID as the continuation or development of new symptoms three months after the initial COVID infection, where these symptoms last for at least two months with no other explanation.
We're still learning about what causes long COVID, but persistent symptoms can be explained by the diverse effects of SARS-CoV-2 (the virus that causes COVID) on different parts of the body. For example, the virus can affect the heart, blood vessels and lungs.
Research suggests long COVID is linked to persistence of the virus in the body long after infection, and this in turn causes dysfunction of the immune system.
SARS-CoV-2 can also affect the brain and cognition, especially executive function, which is the ability to plan, monitor and execute goals. This can result in difficulty performing work tasks and other activities of daily living among people with long COVID.
What we did
We used Australian data to estimate infections in 2022 and modelled long COVID and recovery rates across all age groups to understand the burden of long COVID.
We then used this data in a mathematical model to estimate economy-wide labour supply losses in 2022 and to determine the decline in real gross domestic product (GDP). Economic losses occur because people affected by long COVID may be unable to work, or work at reduced capacity, for a period of time.
We found that at a peak in September 2022, up to 1,374,805 people (5.4% of Australians) were living with long COVID following a single infection. Allowing for recovery from long COVID, up to 3.4% would still be living with long COVID after 12 months.
We estimated long COVID resulted in more than 100 million hours of lost labour in 2022. These lost employment hours translate to an economic cost of roughly $9.6 billion, equivalent to 0.5% of GDP for 2022.
Working-age adults between 30 and 49 were most affected. The estimated labour loss was greatest for people aged 30-39 (27.5 million hours, or 26.9% of total labour loss) who saw the highest overall numbers with long COVID of any age group. People aged 40-49 followed close behind, with an estimated 24.5 million hours lost, or 23.9% of total labour loss.
Higher numbers of long COVID in these younger age groups are likely because they experience more COVID infections, possibly because they are more mobile and mix more with others.
We did not include losses incurred by healthy employees who could not work due to caring for others with COVID or long COVID. Further, we only considered a single COVID infection, and the risk of developing long COVID thereafter. But we didn't consider the risk from reinfections, which increase the likelihood of long COVID. Therefore our research likely underestimates the impact of long COVID.
Long COVID affects people of all ages, and can occur regardless of the severity of their COVID infection. Widespread and ongoing COVID infections means if even only a small percentage of people develop long COVID, this is still a very large number of people.
By way of comparison, 2% of Australians have coronary heart disease, which is the leading cause of illness and death in Australia (and the world). Even if only 3.4% of people have ongoing long COVID, this imposes very large public health and economic costs.
And unlike coronary heart disease, which disproportionately affects older people, our study suggests the impact of long COVID is highest in working-age adults, which is why the economic impacts are so great.
A global trend
Many countries including the United States and the United Kingdom are experiencing similar economic losses due to long COVID, with rising numbers of people unable to work.
Recent estimates indicate roughly 400 million people around the world have had long COVID. The condition may be costing US$1 trillion annually - equivalent to about 1% of the global economy.
The weight of evidence around long COVID and its impact on population health has experts calling for the condition to be factored into policy decisions.
What can we do?
In Australia, it's primarily the immediate outcomes of acute COVID, such as hospitalisation and death, which are used to determine eligibility for antivirals and the importance of vaccines. Healthy people under 70 are not eligible for subsidised antivirals, while vaccines are restricted for children and adult booster rates are low.
But there's strong evidence vaccines reduce the likelihood of long COVID, and some evidence antivirals may also lower the risk. Long COVID should therefore be factored into Australian policy and guidance on antivirals and vaccines.
Other measures that reduce the risk of COVID infection will also reduce long COVID risk. These include a focus on safe indoor air, and mask use in high-risk, crowded places during COVID epidemics, especially in health-care and aged-care settings.
Finally, we need to consider how to support those with long COVID who can't work. Long COVID is the sting in the tail of SARS-CoV-2, and planning proactively for it will reduce the impacts on society.
C Raina MacIntyre receives funding from NHMRC (L3 Investigator grant and Centre for Research Excellence) and MRFF (Aerosol transmission of SARS-CoV-2 experimentally and in an intensive care setting) currently. She currently receives funding from Sanofi for research on influenza and pertussis. She has been on the WHO COVID-19 Vaccine Composition Technical Advisory group (2021-2024). She is the director of EPIWATCH®️, which is a UNSW, Kirby Institute initiative.
Long Chu receives funding from multiple organizations. However, he has received no external funding for this research or for any of his research related to COVID-19.
Quentin Grafton receives funding from multiple organizations, including the Australian Research Council. However, he has received no external funding for this research or for any of his research related to COVID-19.
Tom Kompas receives funding from the Australian Research Council and several other organisations. However, he has received no external or direct funding for any of his research on COVID-19 or Long COVID.
Valentina Costantino does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
