The 21 year-old Yarralumla resident was on university exchange in the United Kingdom when the escalating pandemic problem brought him home.

His initial symptoms could've been passed off as jet lag but common sense told him to get tested and self-isolate straight away.

By the time the result came back positive, he was bedridden and relying entirely on his family to pass meals and medicine down to his end of the house.

For a fortnight his main symptoms were nausea, headaches and fatigue which he managed with help from his family at home.

But months after he was given the all-clear, Mr Greenough said he could not shake the tiredness.

"Five or six months down the track I am probably now just feeling OK," he said.

"Initially that fatigue was intense. I clocked up 13 hours' sleep one night and still woke up feeling tired."

Mr Greenough is one of many people around the world reporting ongoing symptoms weeks and months after recovering from coronavirus.

Researchers from the American Journal of Emergency Medicine and The New England Journal of Medicine are among those who've released papers suggesting COVID-19 may affect the brain long-term.

Owen Butler scoffs at any suggestion coronavirus could cause the same harm as the common cold.

He was unfortunate enough to develop this healthy scepticism when he became one of the 113 people diagnosed with COVID-19 in the ACT.

On holiday with his wife in Europe, the Canberra man believed he contracted the virus from a shopkeeper in Portugal.

Alongside several others who were part of a tour group sightseeing along the Portugal Riviera in March, they both developed flu-like symptoms following an interaction with a storekeeper who was visibly unwell.

Their Mediterranean tour was cut short within days of their arrival as cases began to surge across Europe.

After arriving home in Curtin, it didn't take Mr Butler long to determine the fatigue and sore throat weren't symptoms of travel or a lingering sinus infection.

"When you went down you went down so quickly," his wife, who asked to not be named, said.

The pair self-isolated at home and when their COVID-19 test results came back positive they quarantined from the adult children they shared a house with, who were also required to isolate, from their bedrooms.

Now cleared of the virus, Mr Butler said he felt as if his brain was swollen inside his skull and he aged a decade in just a few weeks.

"Out of a 24-hour day I was sleeping probably 22 hours," Mr Butler said.

"I didn't get a lot of high-temperature sweats like Anne* did, instead I got a lot of brain pressure. I'd get up, have a sip of tea and then go straight back to bed and do it all over again."

The "60-odd" pair said the virus seemed to attack vulnerable spots in the body, causing discomfort from old injuries.

"We were getting up in the middle of the night to go and check on the other just to make sure they were breathing because we were so sick," Anne* said.

ACT Health's advice had been to get up and move around to avoid lung infections.

Anne* credited a course of antibiotics and an antiviral medication, Tamiflu, which is used to treat and prevent influenzas, in helping her to avoid "the man flu" symptoms her husband experienced.

"I have a history of collapsed lungs," she said.

"If anyone should've gotten really sick it should've been me. I can't imagine what it's like for people who get it in the lungs as well, it must be horrendous."

It took her 21 days to return a double-negative test. It took Mr Butler longer to recover.

"We felt more like 50-year-olds before COVID, now our bodies just feel older," he said.

"Your skin ages, your hair seems to go backwards, my nails have become brittle," Anne* said.

"You literally age 10 years in about 10 weeks."

With a background in research, Mr Butler said he was careful not to understate the effect a pandemic and working from home might have on his energy levels had he not contracted the virus.

"There's a whole bunch of things that can be contributing factors in the way you feel, but the thing that is really clear for both of us: the fatigue is very much a thing," he said.

Nobel Prize-winning immunologist, professor Peter Doherty, said there was a lot we didn't know about this disease and there was a lot we didn't know about its lingering impact.

"We've never seen a virus like this," Prof Doherty said.

"We could see a fairly high incidence of long-term consequences and we do know that some of those consequences are very severe.

"We're seeing reports of cardiac problems. We know the virus gets around the body in the blood. We know it can get into the heart. We know you can get virus back from the heart and from the kidneys.

Prof Doherty said he had a theory that people who recovered may end up with 10 years' less of productive life.

"This is all going to gradually come out," he said.

Noela Turner will be 80 this year. She has lived in O'Connor for more than 40 years and been part of the same congregation all that time.

Mrs Turner contracted coronavirus in the beginning of April alongside several other members of her church after coming into contact with a fellow parishioner, who had returned from the Ruby Princess cruise ship.

Unlike the Butlers, Mrs Turner became so unwell she was admitted into the intensive care unit at Calvary Hospital, where she needed oxygen for two days.

"I live alone and I felt I couldn't breathe so I had to call the ambulance to get to the hospital," she said.

For a further two weeks she lived in her pajamas at home, unable to get out of bed for much of the days.

The virus then caused complications with her diabetes, which she managed alone while her son camped out in a trailer in the front yard.

Over the winter weeks family members who were not banned from visiting due to border closures took turns leaving meals and supplies out for her to collect.

She said she felt blessed to have had people able to visit and members of her church praying for her.

"I feel for older people who don't have anyone who are on their own, it certainly would be harder. I feel for the people in nursing homes who are shut in their rooms."

It's now months since Mrs Turner has received the all-clear but she definitely does not feel her old self.

"I have no desire to do anything. I just feel washed-out, like, I just don't feel like doing anything, much," she said.