When Marilyn Cornelius woke up with heavy sinus congestion last month, she wasn’t too concerned. Sisters had been extremely smoky, and this was a common response for her. But then another symptom reared its ugly head:

“As the day progressed, the sudden and severe loss of taste and smell triggered me to go get tested,” she recalled.

St. Charles Health System had just set up a drive-through testing site, and Cornelius waited for an hour in her car, with hundreds of others, to find out whether the delta variant had caught her.

It had. Hours later, her test result posted on St. Charles’ My Chart indicating that she was COVID-positive. She qualifies as a “breakthrough” case — a person who gets COVID-19 despite being fully vaccinated.

“I was fully vaccinated by February, which gives credit to the belief of the vaccine waning,” she said.

Cornelius returned home to isolate in her room and to weather the coming storm. She started looking into the best means to beat back symptoms and recover as quickly as possible. Posted on her chart was a key to facing down the delta variant: monoclonal antibody therapy.

St. Charles Health System had just begun offering a treatment to help people with mild to moderate COVID-19 fight off the disease and — hopefully — avoid hospitalization.

“I would not have known about that if Dr. Carey Allen had not put it on my chart,” Cornelius said. “I started researching that, and got hold of my primary care doctor immediately.”

The treatment uses monoclonal antibodies to mimic the immune system’s natural antibodies, which fight back against harmful antigens such as viruses. The body takes time to produce natural antibodies; monoclonal antibody therapy allows a sick person to fight the virus earlier, which may prevent them from getting sicker and needing to be hospitalized.

Currently, monoclonal antibody therapy is only available to people who are at high risk of becoming severely ill from COVID-19, and they cannot self-refer themselves for the treatment. A physician must make the referral.

Cornelius qualified for the treatment because she had mild to moderate symptoms and an underlying autoimmune disorder that put her at risk of developing more severe symptoms. Her doctor agreed immediately that the treatment was an appropriate option and got her into the process to get scheduled for treatment.

She said she had “one bad night” between diagnosis and treatment, with aches, shortness of breath, and a high heart rate as her body engaged in the battle with the virus. The experience made her acutely aware of one of the most alarming aspects of COVID-19: A person with mild to moderate symptoms can take a sudden and dangerous turn for the worse.

“That’s what’s so scary about it,” Cornelius said. “You do not know. You can think ‘I’ve got this beat,’ and you go around the corner and get hit upside the head and end up in the ER, intubated.”

Knowing that the vaccine offered some protection against development of severe symptoms was reassuring.

“I knew I was going to be OK, because I’d been vaccinated, and I knew this treatment was on the horizon for me,” she said.

Treatment is ideally administered within three days of a positive COVID-19 test or within 10 days of symptom onset.

It’s a bit of a process to make it happen, and the procedure itself takes some time.

“I was there at 5 o’clock, and I got in my car at a quarter to 8,” Cornelius recalled. “I felt pretty wiped out that night.”

The potential benefits of the treatment are well worth navigating the logistical challenges, said Dr. Cynthia Maree, St. Charles’ medical director of infectious disease.

“Right now, this is the only medication we have that is approved under Emergency Use Authorization to be used for outpatient management of COVID-19,” she said. “It has the possibility of keeping people with COVID-19 from developing severe disease or from dying. Obviously, that’s something we want to be able to provide to the community.”

More than 150 patients have received Monoclonal Antibody Therapy as of press time.

Cornelius can attest to the treatment’s effectiveness. She reported that her congestion symptoms cleared within two days of treatment, and even the loss of taste and smell — which can linger for weeks — has abated.

“I would say 50 percent within three days of the treatment; 70 percent within a week,” she said.

Interviewed four days after her quarantine period, she said she feels “absolutely fine.”

Asked whether she had any hesitation in undergoing a new treatment, she said, “No, not at all — because I wanted to protect my family and my community.”

Her family is fully vaccinated, and, according to a report by Bloomberg, recent data shows that the treatment reduces household transmissibility by over 80 percent. Her husband tested negative for COVID.

Cornelius advises people to take measures to protect themselves.

“First of all, I’d get the vaccine,” she said.

And, she says, those who test positive should at least look into the treatment — don’t simply assume you won’t qualify.

“Go to your primary and say, ‘Can I get the monoclonal antibody treatment?’”

Editor’s note: Marilyn Cornelius is the wife of Nugget Editor in Chief Jim Cornelius.