As Ruth Castellanos watched cases of the strange new virus that had shut down China, then Italy and Spain, rise in Ontario last spring, she felt a pang of fear.

“I started thinking, ‘Oh my goodness,’ ” remembers the 38-year-old. “ ‘I hope it doesn’t get as bad here.’ ”

She couldn’t have known at that moment that she would soon become a case herself, part of a first wave of infected in the province who faced a terrifying disease that doctors knew little about.

Now, as they watch cases spike again, those patients have unique insights for those who will get this fall. People who, like them, will suddenly find themselves with strange symptoms or a positive test. And who can hopefully learn from them about everything from the importance of getting tested to the range of outcomes — and the little things that make it a bit easier to cope.

When Castellanos, a Hamilton college instructor who’s still unable to work, first became ill in May, she thought it would be over in a few weeks.

She thought it was just a respiratory virus.

She was wrong.

Still facing a constant “bombardment” of symptoms, from brain fog to a racing heart rate, she wants others to know that they can last for months.

“If you’re feeling any symptoms that you never felt before, fight for yourself to get help and get treated, because it’s not in your head,” she said.

“It’s affecting your brain, your heart, your organs, your stomach — it’s affecting everything.”

Castellanos, once an active avid gardener who now gets exhausted making dinner, is part of a group that call themselves “long-haulers,” people still struggling with lingering symptoms of the virus.

She said it’s important to know that if you’re not critical, you’ll be largely left to fend for yourself at home. She made it through with the support of her husband, and her dog, Buttons, who never left her side.

She tried to take her mind off the situation by watching funny shows, like all 60 episodes of a Spanish soap opera, and freezing meals, so they’d be available on days she was too tired to cook.

It’s also good to have people you can count on “on speed dial in case you need help,” she said.

Castellanos eventually tested negative. If too much time elapses between the first symptoms and testing, this can happen, experts say. She was told by one doctor she definitely had COVID-19, a clinical diagnosis she feels should be treated as just as important as a positive test, especially as testing was not open to everyone in the early days of the pandemic in the province.

She eventually found a physical medicine and rehabilitation specialist on her own to consult about her persistent symptoms. Her advice is to “seek medical help, and if you’re denied, keep pushing.”

If a family doctor doesn’t have the answers, ask them to send you to someone who might know more, she said.

Getting tested quickly is one of the most important things to do, said Susie Goulding, another long-hauler, so that a lack of a positive test is not a barrier to care later.

Goulding, who’s also been struggling with a range of symptoms since late March, initially did not qualify for testing, because she hadn’t travelled and didn’t have a fever.

Although, like Castellanos, she was also told by a doctor to assume it was COVID-19, she was negative by the time she finally got the test.

“You need to go right away and get tested, because if you don’t get tested and if you have it, you could potentially end up a long-hauler and you might have difficulty trying to convince people that you actually have COVID-19,” said the 52-year-old Oakville floral designer, who’s still not able to work.

“A proper diagnosis is key.”

She also recommends having Tylenol, a thermometer and a pulse oximeter, a small device that measures oxygen levels in the blood at home.

But it’s hard to prepare in advance, because “the thing is that everybody displays such different symptoms.”

It’s like “putting your hand into a grab bag and pulling out a fistful of symptoms and that will be how your body reacts and how your COVID-19 journey is going to be,” she said.

It’s also important to look out for mental health, and get support for the anxiety and depression that might follow the isolation and trauma related to COVID-19, she added.

In June, Goulding started on Facebook, which now has more than 4,000 members. It’s been critical, she said, to connect with other survivors from across the country, who can share experiences, advice, research — even the names of specialists or studies that they’re involved in. This peer support has been essential, she said, especially as long-haulers are left without a one-stop shop for followup care. They’ve had to advocate for themselves, as they realized in real time just how devastating COVID-19 can be.

“I never thought in a million years that I would catch it,” she added. “It’s a monster of a virus.”

That’s something Heidi Robertson knows all too well. Her husband Torry, a nurse who worked in Michigan, across the border from their LaSalle, Ont. home near Windsor, got COVID-19 in March.

The 46-year-old “basketball dad” and “big teddy bear” “never got sick prior to this,” she said. Other than high blood pressure, he didn’t have any underlying medical conditions.

She warns others not to assume that just because they’re younger and healthy that they’ll be fine.

For Torry, shortness of breath was a later symptom, after vomiting, fever, loss of taste and smell, and diarrhea, but things quickly went downhill after that started.

He was taken to the hospital in an ambulance at the end of March.

Weeks before, he had told his wife that he didn’t want to be put on a ventilator if he got the virus.

In early April, over FaceTime, after doctors told her it was needed, she asked him if he’d changed his mind.

“He looked at me — he looked so weak — and he said, ‘I’m OK with it.’ He said, ‘Tell all the kids I love them, and I love you,’ and that was it,” she remembered

He spent seven terrifying weeks in the ICU, and 38 days on the ventilator, going into kidney failure at one point and needing dialysis.

During that time, Robertson said she stopped going on social media and reading about other cases online. Instead, she only listened to the doctors and nurses treating him, cutting out all the noise.

Torry was discharged from Hôtel-Dieu Grace Healthcare in Windsor earlier this month, but is left with a severe brain injury that has impacted his speech and balance. He’s continuing outpatient rehab.

“We just take it day-by-day,” Robertson said, adding she’ll always be grateful to the team that saved his life. “It’s been such a long road, and we have so much more to go.”

She’d tell others in the same spot to just keep putting one foot in front of the other, try to stay positive and have faith, even in the face of so many unknowns.

“Ask a lot of questions of the doctors,” she added, “and let the doctors know anything that has been going on with your loved one.”

Most people will not have such dramatic tales of COVID-19. For some, there will be no symptoms.

For others, it will feel like almost nothing.

But, said 20-year-old Hannah Abrahamse, that doesn’t mean it’s something to take lightly.

The Trent University English major was studying abroad in England when Prime Minister Justin Trudeau told Canadians to get home fast. She threw a few things into a suitcase and arrived in Toronto in late March, isolating in her grandmother’s empty house in Orillia.

About 10 days in, she started noticing a stuffy nose. She was sneezing, with watery eyes, a headache, a little bit of a sore throat, but no fever or cough.

Fearing for her mom and brother, who are immunocompromised, she pushed to get tested, and was turned away from an Orillia assessment centre twice because her symptoms weren’t serious enough.

Finally, after a referral from a family doctor, she got the test in early April and was stunned at the result: positive.

“I wasn’t even really concerned at all by my symptoms, because I didn’t feel very sick. I just thought, ‘Oh, this is really weird and bad timing. I have these bad allergies, probably because I’m back in Canada,’ ” she remembered.

“It was a good thing that I did, because otherwise I wouldn’t have known that I had COVID-19.”

She’d advise others to do the same.

The worst part of a mild bout with the disease, she said, was the isolation.

Watching the Netflix documentary ‘Tiger King’, doing lots of YouTube yoga, FaceTiming friends, and porch-drops of chocolate chip cookies from an aunt helped pass the time.

“I was glad to do it to keep everybody safe,” she said.

“What I want to make clear is it’s not about you, it’s about other people.”

Abrahamse was in a position where she could clearly see the chain of possible transmission, from herself to her mom or brother, and how her actions would directly impact others.

Many people might not see that so clearly, she said, but it will still be there.

She’s been hearing about some of her peers lately who are going to parties or seeing lots of different people every night — who shrug and assume since they’re young, they’ll be fine.

“And that’s really frustrating, especially because you can get it and not know if you don’t take your symptoms seriously, or you can be totally asymptomatic,” she said.

The best advice, agrees long-hauler Goulding, is to try not to get COVID-19 in the first place, so that you don’t pass it on to anyone else, or risk a complicated battle with it yourself.

“Take all precautions in trying to avoid it,” she said, “Like the plague that it is.”

May Warren is a Toronto-based breaking news reporter for the Toronto Star. Follow her on Twitter: