A recovered coronavirus patient saved 2 lives after donating her blood plasma. She says she's 'still coming to terms' with that ability.

• Marisa Leuzzi doesn't know how she was exposed to the coronavirus, but the infection led her body to develop antibodies to the disease.
• Leuzzi was the American Red Cross's first donor of convalescent plasma. That helped save the lives of two critically ill patients: her aunt and a "complete stranger."
• Doctors were afraid that Leuzzi's aunt would succumb to COVID-19, but her blood-oxygen level increased and vitals stabilized within hours of the infusion.
• Medical experts say rigorous clinical trials and more robust scientific evidence about the effectiveness of plasma therapy could take it from a "Band-Aid" to a "panacea."
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Marisa Leuzzi's primary care physician told her in March that she had the flu. Leuzzi had a high fever, some gastrointestinal discomfort, and a slight cough. But she hadn't traveled or knowingly come in contact with a coronavirus patient, so COVID-19 seemed unlikely.

Still, Leuzzi, who is asthmatic, was convinced something else was at play. She went to a drive-thru coronavirus testing center in Pennsylvania, where she lives, for "peace of mind."

Her instincts were right: She had COVID-19.

Less than two weeks after recovering from the illness, Leuzzi became the American Red Cross's first donor of convalescent plasma — an antibody-rich blood component that is obtained from patients who have recovered from infection diseases. Her donation helped save the lives of two coronavirus patients, one of whom is her aunt.

"I'm still coming to terms with it," Leuzzi told Business Insider. "But I'm so happy that I could take something from my experience and make a positive out of me having COVID-19."

'Roll up a sleeve' to help

Leuzzi's aunt, Renee Bannister, is 63 years old and works as a teacher in New Jersey. She contracted COVID-19 around the same time as Leuzzi, but her case was more severe: Bannister was hospitalized with a high fever and severe respiratory distress.

The pair hadn't seen each other recently and neither knows when or how they were exposed to virus.

But when Leuzzi came across reports about experimental blood-related therapies to help patients fight the virus, she reached out to Bannister's doctor at Virtua Hospital. He looped in the Red Cross and Mayo Clinic; about four days later, on March 31, Leuzzi was "hooked up" to a plasmapheresis machine at a Red Cross center in Pennsauken, New Jersey. The extraction process took about two hours and was "completely painless," she said.

Dr. Erin Goodhue, executive medical director for the Red Cross, told Business Insider in an email that the group is witnessing "the best of humanity as people roll up a sleeve to help those in need."

"We are seeing individuals like Ms. Leuzzi give of themselves to help the most vulnerable COVID-19 patients fight back," Goodhue said.

'They didn't know if she'd make it through the night'

By the time Leuzzi's blood-plasma donation reached Bannister on April 3, she was on a ventilator. Doctors told the family that "they didn't know if she'd make it through the night, including the night before her infusion," Leuzzi said.

But, within a few hours of receiving Leuzzi's plasma, Bannister's blood oxygen level jumped 17%.

"In the next three to five days, we started to see the rest of her vitals improve, such as her blood pressure and heart rate, and her fever started to come down," Leuzzi said. "By about the fifth day, we saw all her vitals stabilize."

A 61-year-old man from New Jersey who Leuzzi said is a "complete stranger" to her also benefitted from her plasma.

"That was news to me," she said. "We were under the impression that my aunt got all my plasma. We found out just a few days ago ... that they had some extra plasma and were able to use it on another patient who was in the same hospital."

The man "was just at the right place at the right time," Leuzzi said, adding that his recovery looked much the same as Bannister's.

Doctors were surprised by the quick recoveries

On April 14, Bannister was taken off the ventilator. She'd been on it for 22 days.

Bannister was discharged from the hospital on April 21 and is now in a rehabilitation center for physical and occupational therapy so she can "continue her recovery and rebuild her strength," Leuzzi said.

She added that Bannister is "doing very well," remains in "good spirits," and will likely return home in May.

The other recipient of her plasma has also been taken off a ventilator.

It's hard to say if or how much the plasma helped the two patients, Leuzzi said, but she noted that the doctors "were pretty surprised that they turned around as quickly as they did."

Dr. Graham Snyder, medical director of infection prevention at the University of Pittsburgh Medical Center, told Business Insider that convalescent-plasma infusion treatments were first tried in the 19th century.

They're largely "reserved for infections where there is no immunity in the population, and no vaccine or other treatment," he said. Recent examples have included Ebola and MERS.

Snyder underscored the need for rigorous clinical trials of the approach in coronavirus treatment.

"What we have are reports of small groups of patients who received the treatment [and] did better, but without comparison to other patients," he said. "So we can't estimate what would have happened if they didn't receive treatment."

Being your 'own advocate'

Meghan May, a professor of infectious disease at the University of New England College of Osteopathic Medicine, said direct plasma transfers from recovered patients may serve as "a bit of a Band-Aid."

"That said, the underlying principle — the transfer of antibodies to help sop up and neutralize virus in critically ill patients — has the makings of a panacea," she told Business Insider.

What's needed, she said, is for the antibody-making process to move from patients' bodies into laboratories and gain FDA approval. That way, plasma infusions too could be scaled up.

May highlighted Herceptin, a cancer treatment that's based on antibody therapy, as an example of a treatment that used a similar approach.

"Absent an antiviral drug, antibody therapy could be a helpful addition to support treatment until a vaccine is discovered," May said.

Leuzzi said she hopes her story will show others the value of being your "own advocate" and encourage recovered COVID-19 patients to donate convalescent plasma and "see what a difference it can make."

"It's an amazing feeling" to have been able to help two people, Leuzzi said.