Nic Goodrich is an exercise junkie. The 45-year-old would hit the iron three or four nights a week, then walk the dog five kilometres every day. On top of that, he’d cram in two games of cricket and had just started a full-time job teaching at TAFE.
“Everything was going really well, everything was positive,” Goodrich says.
He went away with friends to celebrate the new year of 2022, and came back with COVID-19 – and just never got better.
Goodrich’s mind became cloudy. He slept but never felt rested. A headache appeared and never left.
The brain fog was immense. “Like, I would forget the word mid-sentence and then I would forget the topic that we’re talking about mid-sentence, as well.”
Goodrich kept working as long as he could, pushing back against the symptoms and waiting for them to get better. So far, they haven’t. It has been 15 months since he first caught the virus, and six months since he reduced his working hours to part-time. He’d like to stop but he cannot afford to.
After waiting three months, Goodrich got an appointment with a long COVID clinic. “They didn’t have any real answers … or knowledge or anything of what was happening,” he says.
Goodrich’s story is both strange – a mysterious, life-altering illness – and typical.
Federal parliament’s inquiry into long COVID, due to report shortly, received almost 600 submissions, many telling the same story. Lives turned upside down. Too little support, financial or medical. An illness that confounds them and their doctors at every turn.
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What is long COVID – and how many people have it?
At present, definitions of long COVID are broad; the World Health Organisation notes more than 200 different symptoms have been reported, across multiple organs.
Hallmark symptoms include chest pain or a pounding heart, abdominal pain, nausea, brain fog, fatigue, memory loss, ringing ears, erectile dysfunction and irregular menstruation.
If these run for longer than three months after acute infection, and there’s no other obvious cause, a doctor can diagnose long COVID. Full recovery can take months or years.
Goodrich lists headaches, a sore throat, arthritis-like joint pain. Michael Tiffin struggles with a cough that has never gone away, shortness of breath, low blood-oxygen levels. He can barely climb the steps up to his house.
“Walking up those six steps … It was literally like you played the hardest game of footy, did the biggest run or hardest training that you’ve ever done, and it takes you an hour to recover afterwards,” Tiffin says.
The two men have different symptoms but the same diagnosis. A broad definition of long COVID has ensured that people aren’t denied a diagnosis.
But it has flaws. In particular, it limits scientists’ ability to study the underlying causes because it seems likely to encompass several syndromes caused by COVID-19. Their studies end up muddied.
“The current state-of-the-art in what’s labelled as long COVID is a complete dog’s breakfast,” says Professor Andrew Lloyd, director of the University of NSW fatigue clinic. “As soon as you say that, everything anyone says that follows is also a dog’s breakfast.”
It is that diversity of symptoms that suggests “there’s not one single long COVID”, says Professor Tom Marwick, who is leading a study of long COVID at the Baker Institute.
When it comes to a simple question of how many people have it, says University of Tasmania disease modeller Professor Martin Hensher, the answer is closer to “we don’t want to know”.
“In Australia right now, it is not possible to know. Quite simply, the measurement is not in place. And this has gone on a very long time,” Hensher says. “And there are plenty of people who feel one of the reasons this is not being measured is because it suits some interests not to know.”
Unlike the US or UK, Australia does not have any national survey attempting to measure the number of people with long COVID symptoms.
Some things we do know: women are more likely to get it than men, and younger and middle-aged people are more likely to be affected than the elderly – a reverse of the risk posed by acute infection.
But the evidence on prevalence varies enormously.
If that survey truly reflected the presence of long COVID in the population, we’d be talking about more than a million Australians with the condition by mid-2022.
International data is similarly all over the map. The UK’s tracking survey suggests 2.7 per cent of the population had symptoms more than three months after infection; the US’ survey found 14.7 per cent of Americans said they had experienced long COVID.
The numbers aren’t static. “Most people who develop long COVID see improvement or recovery over time,” says Hensher. As some are falling sick, others are recovering – meaning the true number is ever-shifting.
Modelling those findings in Australia translates into a lot of variance. Modelling released by Hensher’s team estimates there are between 189,000 and 540,000 long COVID cases, and were between 64,000 and 110,000 severe cases in early December.
This is a huge number of newly sick people the healthcare system, already buckling under demand, will need to care for. At the moment the wave has not hit – because sadly, there’s often little that medicos can do for patients with long COVID.
“If that changes, it is a significant chunk of completely new healthcare demand,” says Hensher.
Add this to the evidence people who have had COVID-19 are more likely to fall prey to other illnesses, including kidney disease, diabetes, stroke and heart disease, and you could be putting the healthcare system under real pressure.
“The really big question is: over the coming years, how does this really play out?” says Hensher.
Karren Hill first contracted COVID-19 on a holiday in South America in April 2020. At that time, only a few hundred Australians had the virus, and doctor knowledge of COVID symptoms – let alone long COVID symptoms – was minimal.
“You were really on your own, and that’s why I had to look overseas for answers.”
She developed breathing problems, and then a heart issue.
“When I was having the breathing problems, I came straight to the hospital and they didn’t want to see me. They said to me, ‘If you can speak, I don’t need to give you oxygen yet, and that’s all I can offer you’,” she said.
Hill’s experience mirrors that of many people with long COVID: Getting a diagnosis is a real struggle. What patients really need is a biomarker – a signal that shows the presence of the disease, like high cholesterol warns of circulation issues.
They don’t yet have access to the technology – but it might be on the way.
“We’ve got multiple biomarkers for it already – including some completely new discoveries,” says Professor Jeremy Nicholson.
Nicholson heads the National Phenome Centre, a new institute that uses advanced screening technology to measure a person’s “phenome” - a measure of their biological health using chemical and biochemical markers in blood or urine.
His team has been following 215 people infected with COVID-19 early in the pandemic, tracking their recovery by both looking at their symptoms and monitoring their blood.
Their work has shown how COVID damages systems right across the body. Everyone has different levels of damage to different organs, and they recover at different speeds. “We call it a disease mosaic because it’s built of lots of different bits,” Nicholson says.
In a paper in Nature Immunology in January they showed a complex series of biomarkers, mostly related to inflammation, could predict with a high degree of confidence who would recover quickly and who would take a long time.
His tool is not yet ready for the clinic; tests like nuclear magnetic resonance spectroscopy require expensive and specialised hardware, and the work needs to be validated on a larger group of patients.
But his data suggests there is a central villain driving much of the disease.
“Long COVID, in most cases, does not come from the original viral injury,” Nicholson says, “it comes from the immune response to fighting off the virus.”
Long COVID is not a medical mystery never seen before. Many viruses, including the coronaviruses that caused SARS and MERS, often leave people with long-lasting symptoms.
“Every person on the planet probably experiences lingering symptoms after a nasty bug,” says Lloyd.
Many scientists suspect chronic fatigue syndrome is often the result of a viral illness – and it’s possible the mechanism is similar (it’s also notable the symptoms strongly overlap).
A range of viruses are known to remain dormant within our bodies, often for years. For example, the Epstein Barr virus causes harmless childhood infections before turning dormant. In most people, this causes no problems – but a stressed immune system can lead the virus to reactivate. That reactivation is thought to partly drive chronic fatigue syndrome; studies now show evidence of reactivation in some people with long COVID.
That’s one mechanism, but scientists are growing confident long COVID is likely caused by several different overlapping mechanisms, which means there are several different diseases we have lumped into one.
In some cases, people could simply have symptoms from a virus that wreaked enormous damage on their bodies. In a study on patients with long COVID, Professor Marwick’s team at the Baker Institute found about 15 per cent had subtle changes in heart function, possibly caused by heart-scarring. However, in the study those subtle changes did not seem to be strongly linked to changes in functional capacity – another frustrating dead-end.
The virus could be continuing to circulate in small pockets of the body – the gut is a particularly suspicious target, given some people with long COVID report stomach problems. Or micro-clots could be damaging the circulation system.
Studies looking at the immune system have found a plethora of signals suggesting it is not working as it should. T cells are exhausted and in low numbers, while interferons – a signal protein that usually means an infection is present – seem elevated long after the infection has passed. Other studies find levels of autoantibodies, which wrongly target the patients’ own tissue.
Closely related is inflammation – agitation of the immune system, usually in response to damage or attack. We know COVID-19 infection leads to a huge inflammation response as our immune systems fight back against the invader. But evidence suggests that in some people with long COVID, this system does not return to normal when the virus is beaten.
“It is almost entirely inflammation driven,” says Professor Nicholson, “except if there is lung scarring from acute severe COVID”.
When Stephenie Watts presented to hospital struggling to get her legs to move in sync, neurologists discovered inflammation in her brain stem and frontal lobe. She now struggles with severe cognitive impairment and short-term memory loss.
“If the TV is on and my family’s talking, I can’t concentrate on both … if there’s birds outside, they would sound as loud as the conversation and the TV. So you can’t determine what to focus on and what’s important.”
Chronic inflammation could be responsible for the fatigue and brain fog many patients experience, as their overactive immune systems send inflammatory messages to the brain, says Lloyd.
Alicia Newnham’s initial COVID infection was mild, and she happily went back to work. But a week later it caught up to her.
Newnham went to her GP complaining of extreme fatigue and a heart rate that spiked to 130 bpm just by rolling over in bed.
“I’m the person who normally just keeps going, but I just woke up one morning and thought, “What’s wrong with me?” she said. “I sat on the edge of my bed and just couldn’t move. Everything in my body was hurting and screaming at me.”
Symptoms of brain fog and fatigue, combined with a fast heartbeat and difficulty standing, are consistent with POTS – postural orthostatic tachycardia syndrome.
Our autonomic nervous system is the unconscious control system that keeps our heart beating, our lungs breathing and our gut moving – and, importantly for long COVID, runs the valves in our blood vessels that keep shunting blood to the brain.
POTS is characterised by a fast heartbeat and difficulty standing, as the autonomic system’s control breaks down.
“If you’re not giving people brain blood flow when they need it, they are never going to be able to tolerate everyday activities,” says Marie-Claire Seeley, CEO of the Australian POTS Foundation.
“What happens is the people who get it tend to get a plethora of quite subtle symptoms. Fatigue, brain fog, blurred vision, they can’t concentrate. That usually escalates to gastrointestinal discomfort.”
This could be caused by direct infection of nerve tissue, or by messing with the immune system, which experts now know is tightly interlinked with our nervous system.
POTS, like many conditions linked to long COVID, seems to occur more in females than males.
Along with all the other post-viral syndromes - like chronic fatigue syndrone - they are poorly understood because they were female-dominant diseases that were maligned as psychogenic. “No money got put in them, no research got put in them,” says Seeley.
For those with long COVID, answers can’t come soon enough.
Hopefully this kicks off a big medical research drive and they start finding some answers, says Goodrich, “because there’s going to be some”.
“If I was making this up, I would have given it up after 15 months.”
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