A Pulitzer Prize winner has warned a "mass disability event" is already under way, as numbers of those suffering long-term symptoms after having Covid continue to grow. 

And the growing crisis could put more pressure on an already struggling health system across the Tasman, as well as see thousands of people forced to leave their jobs for health reasons. 

Ed Yong, a science writer at The Atlantic, has been chronicling symptoms of sufferers post-Covid since the beginning of the pandemic in 2020, when the term "long Covid" was yet to be coined. 

At the time, tens of thousands of people across the world, known as "long-haulers", began reporting debilitating symptoms even after they recovered from their initial illness. 

"I first wrote about them in early June," Yong wrote in August 2020. 

"Since then, I've received hundreds of messages from people who have been suffering for months – alone, unheard and pommelled by unrelenting and unpredictable symptoms." 

The Washington-based journalist's collection of work on long Covid in 2020 earned him the 2021 Pulitzer Prize for Explanatory Reporting. 

'Mass disability event' 

Two years since Yong began reporting on long Covid, he told news.com.au he is still receiving emails "from people who've been dealing with symptoms since near the start of the pandemic, and others who've started down that path more recently". 

He's warned that the huge number of infections seen by Omicron and its predecessors will see millions of people around the world affected by a "mass disability event". 

"Even if you take the most conservative estimates for the proportion of people with Covid who develop long-term symptoms, that still translates to tens of millions of people worldwide," he said. 

"Some of those people will recover, but others will be disabled for the foreseeable future. 

Long Covid has more than 200 different symptoms across 10 organ systems. Photo / Getty Images 

"The scale of such a mass disability event is truly hard to imagine, and it is appalling that we are forced to imagine it because two years on, long Covid still isn't being counted, and many long-haulers are still being ignored." 

Yong likened long Covid to other "marginalised" diseases. 

"The piece I want to highlight, and that I think a lot of people still miss, is that long Covid has important similarities to ME/CFS, dysautonomia and other chronic, complex, marginalised conditions. 

"There aren't many scientists who study these conditions but they do exist, and their work means that we're not starting from scratch when it comes to understanding long Covid. 

"Even many scientists are unaware of this, and are thus reinventing the wheel." 

More than 200 symptoms 

Long Covid has more than 200 different symptoms across 10 organ systems associated with it, according to research conducted in Canada late last year. 

The most common include ongoing debilitating fatigue, brain fog, shortness of breath, pain, sleep disturbances, anxiety and depression. 

Other symptoms include muscle weakness and joint pain, stomach and intestinal symptoms such as diarrhoea, psychological effects like mood swings, and sensory symptoms such as changes to smell or taste. 

Long Covid cases in Australia before the Omicron wave were estimated at 20,000. Photo / Getty Images 

Individuals with the post Covid-19 condition may also have impaired cognitive and physical functional status, including limitations in the ability to perform daily activities such as dressing or bathing, reduced ability to care for family members or dependants, difficulty returning to work and increased health care use. 

Insane numbers in Australia 

The World Health Organisation (WHO) has reported that about one in four cases experience symptoms of long Covid for at least a month, and one in 10 experience symptoms lasting beyond 12 weeks. 

In Australia, a study by associate professor of health systems financing and organisation at Deakin University Martin Hensher examined the 2021 Delta outbreaks in Victoria and NSW where nearly 140,000 people had already been infected. 

"It is clear that a number of people developed long Covid [in Australia] following the first wave," he told news.com.au. 

"People start to feel better and then often overdo it and relapse." 

Before Omicron, he predicted the combined outbreaks had led to up to 20,000 Australians having developed long Covid. 

Along with a piece for The Conversation, Associate Professor Hensher calculated that limited relaxation of public health measures "could generate 10,000 to 34,000 long Covid cases" while a complete relaxation of public health measures "could lead to 60,000 to 133,000 long Covid cases". 

Of that number, 2000 to 11,000 people might still be sick a year after their initial infection. 

But those are underestimates in the current climate. 

Associate Professor Hensher warned that with the current outbreak in Australia, it was "foolish" to think there wouldn't be cases of long Covid. 

If you have COVID-19, this video explains what to watch for and when to seek medical advice. Video / Health Navigator NZ 

"[It's] possible that Omicron might behave similarly to earlier variants in terms of long Covid, because remember, with Delta and the original strain, from what we understand with long Covid, is that it's entirely possible for people with quite mild infections to go on to develop long Covid. 

"I think it would be foolish to assume that we won't get significant long Covid cases coming out of this," he said. 

"There's just so many people getting sick that that kind of arithmetic is going to crunch through." 

- by Matt Young, news.com.au