They stayed home, only went out on essential errands and sanitized every surface, but Mark Clements and his germ-conscious wife Debby still got COVID-19.

And Debby Clements, 47, is now on a ventilator in the ICU of the Moncton Hospital.

Her family hopes she'll soon get treatment of her symptoms as part of a national trial involving convalescent plasma. On Friday, daughter Avery Tower, who also tested positive, was appealing for help from people of certain blood types who've already had the illness.

"If you're able to help my mom please consider helping my mom cause she's the only one I've got," Tower posted

The family members have no idea how they came in contact with the coronavirus.

"She's a germaphobe," Mark said of his wife. "She was wearing a mask and gloves before it was fashionable to do so, and she still got it. And I got it."

Tower, who lives in a separate home, suspects her parents caught the virus through a community transmission.

Tower said the couple even ordered their groceries online to avoid going to the store. She would drop things off for her parents, but eventually "everyone just started getting sick."

Two get better, one gets worse

Mark said the progression was quick.

He started to feel symptoms two weeks ago — headaches, fever, and a loss of smell — and called 811. He was tested at a drive-thru testing site in Moncton and got his positive results back a day later.

Then his wife and daughter started feeling sick, and their tests, too, came back positive.

Horizon Health has a testing centre at the Moncton Coliseum. It won't say if it's taking part in a national trial of a treatment for COVID-19 that involved convalescent plasma. (HorizonHealthNB/Twitter)

But while father and daughter started to feel better after a week, Debby got worse.

"She has asthma, so she had a hard time getting breath and was coughing quite a bit," Mark said.

People who already have lung problems are among the groups vulnerable to the most serious effects of the respiratory illness.

Debby was taken to the hospital, where she was prescribed some puffers for her cough. Two days later, she wasn't feeling any better. She returned to the hospital.

"They did a chest X-ray and found pneumonia in both her lungs," said Mark. "That was Sunday. She's been in the hospital ever since."

Debby has now been moved into the ICU and hooked up to a ventilator to help her breathe, Mark said.

Avery Tower, left, says she is trying to find a blood donor match for her mother, Debby, right. (Avery Tower/Submitted )

The family is hoping a transfusion of convalescent plasma — the liquid portion of blood that contains antibodies which protect against illness — will help Debby recover.

Doctors told Mark and Tower the treatment is relatively new. It involves using the plasma of recovered COVID-19 patients in hopes the antibodies will help reduce symptoms and speed up recovery.

Researchers across Canada are now helping with a trial to test the treatment. The trial, which includes 50 Canadian institutions, is expected to last about three months and involve more than 1,000 patients.

With no vaccine likely to be available for at least a year and a half, some experts believe convalescent plasma is an alternative.

After testing positive for COVID-19, Debby Clements was hooked up to a ventilator like this one to help her breathe. (Jean-Pierre Clatot/AFP via Getty Images)

Horizon Health Authority would not confirm it was taking part in the clinical trial and said Saturday that it did not want anyone calling the hospital with offers to donate blood.

Horizon was aware of Facebook posts on the topic but said it could not comment on individual cases or on treatment.

In announcing its own role in the trial, Canadian Blood Services said earlier that it will contact potential donors "based on defined criteria, which will be approved as part of the clinical trial protocol."

The organization, which is collecting and preparing the convalescent plasma for the trial, said the pool of potential donors is small so far, but it's growing.

Researchers with participating hospitals in Quebec said the plasma is to be collected about a month after a patient recovers, when antibody levels are at their highest.

Debby's blood type is AB positive, so a donor's blood type has to be either AB positive or AB negative.

"From what I gather they're trying to compile a list for people who have had [the illness] and have their blood type," said Mark.

Coping together

Since Debby went into the hospital, Tower, her husband and their four-year-old daughter have moved in with her dad to help take care of him and keep him company.

"If we're going to be isolated, we might as well be isolated together," said Mark.

All four are quarantined. Public Health won't test Tower's husband or daughter because they don't have any symptoms.

The family isn't allowed to visit Debby in the hospital but calls daily to get updates on her condition.

"This is really hard," said Tower, who hasn't talked to her mother in over a week.

"So we're just trying to keep hopeful and praying and keeping good vibes out there. I know my mom is a fighter and she needs help from the community."

Mark and Debby Clements, shown here with their granddaughter, both contracted COVID-19, but while Mark recovered early, Debby's condition got worse. (Avery Tower/Submitted)

For Mark, having his granddaughter around the house is helping him cope through the stressful situation.

"She keeps us entertained," he said.

The need for a blood type match is what is keeping Tower distracted, but Horizon suggested Saturday that she not bother encouraging people to donate. The hospital has already received many calls.

"Approaches to the treatment of COVID-19 are evolving quickly," Horizon said in an email to CBC News. "If there is a need to involve recovered COVID-19 patients, those patients will be contacted directly."