27-year-old Molly DeMellier donated her blood for the Mount Sinai antibody trial after she recovered from COVID-19.
The trial hopes to use the antibodies of people who've recovered from COVID-19 to treat those who currently have severe cases.
DeMellier's blood didn't have enough antibodies to be used in the trial. Her experience underscores questions about how antibodies work and what it means for recovered patients' immunity.
Researchers and doctors are still studying coronavirus immunity and are unsure if a person can get COVID-19 twice.
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On March 21, 27-year-old Molly DeMellier finally got the call she'd been expecting for days.
Four days earlier, after waking up with a sudden onset of a tight chest, body aches, extreme fatigue, and a fever, she had gone to an urgent care center two blocks from her New York City apartment for a coronavirus test.
The doctor on the phone confirmed she had COVID-19, the disease caused by the novel coronavirus.
DeMellier rode it out at home. Her chest tightness and cough alarmed her, but she didn't want to get an Uber or public transport to the hospital, inevitably exposing herself to other people. On her worst days, it hurt to even watch TV, so she would sleep all day. On her best, pain relief helped to ease her joint pain and headaches. After about 10 days of symptoms, DeMellier woke up on March 25 symptom-free. She waited three days before going outside again.
Overwhelmed by her experience, she discussed it on the sex and relationships podcast she co-hosts, and soon after a fan got in touch telling her to apply to the Mount Sinai antibody trial, a program seeking blood plasma donations from people who have survived COVID-19, in the hopes that it could be used to treat people in the ICU.
DeMellier knew she wanted to help in any way she could after feeling helpless in bed for two weeks, so she applied right away.
She was accepted, and went in to donate a month later, as directed. But her experience highlights the unanswered questions doctors have about COVID-19, and whether we can be sure that all people who've had the disease will develop immunity.
Why survivors' blood could help people in the ICU battling COVID-19
Mount Sinai's trial is one of a number across the world looking into serum therapy as a possible treatment for people with critical cases of COVID-19, a little-understood disease. It is the second hospital in the United States to receive FDA approval for antibody tests.
Antibodies are proteins produced by plasma cells in the blood that help fight off bacteria and viruses. The immune system generates them as a first line of defense when an unknown "intruder" substance enters the body.
Serum therapy, where the antibodies of a recovered sick person are injected into a sick person to help boost their own immune response to a certain type of disease, has existed since 1891 and won a Nobel Prize in 1901 for its uses in treating diphtheria and tetanus. More recently, serum therapy was used to treat Ebola patients.
The same approach is being held up as a promising treatment for COVID-19, partly because there are few other options at this point. Antibodies are always specific to the pathogen, so it will only work for COVID-19 patients if doctors use plasma from someone who's recovered from COVID-19.
There are plenty of caveats. Serum therapy can't be widely instated because it requires donors and recipients have the same blood type. Additionally, a donor has to donate a lot of blood to yield enough plasma, and that will still only be enough to help two sick patients, USA Today reported. There are also concerns that the tests used to measure antibodies may not be perfectly accurate: they may spot antibodies for other pathogens, or present false positives.
The biggest obstacle is that it's unclear who develops antibodies, who doesn't, when they do, and why. For example, one not-yet-peer-reviewed study from China found that 6% of the 130 recovered COVID-19 patients studied didn't develop any detectable antibodies, and 30% developed very low amounts. The researchers also found that older patients developed more antibodies than younger ones.
It takes 14 to 21 days to develop immunity to COVID-19, according to Mount Sinai's research
To get accepted, DeMellier had to answer online questions about her illness, her symptoms, and when her symptoms subsided. Soon after, a Mount Sinai employee called and scheduled an appointment for April 9 to ensure it had been more than 12 days, the amount of time they believe it takes for antibodies to show up in the blood.
Generally speaking, antibodies are at their highest when a person is almost recovered from the virus. When it comes to COVID-19, though, there's still much uncertainty about when antibody levels peak for the recovered, Dr. David L. Reich, President and Chief Operating Officer of Mount Sinai, told Business Insider.
"My position as a hospital president, I've been following everything that's been going on in the laboratory, but our impression is that the practical use of this test would be to look for people who develop immunity usually 14 or 21 days after the illness," is diagnosed, because that's when the researchers have observed peak antibody levels.
Getting into the Mount Sinai trial
When the morning came, 15 days after her symptoms subsided, DeMellier confirmed with Mount Sinai that she felt well and, wearing a mask, took an Uber uptown to East 102 Street. Her driver had stuck a plastic sheet between them, creating a makeshift wall for extra protection.
On arrival, she was greeted by a security guard, then ushered to a healthcare worker who asked if she had any lingering symptoms. She was given a fresh mask, had her temperature and blood pressure taken, then sent upstairs.
"It was kind of eerie, to be honest," DeMellier told Business Insider. "I actually saw all of the nurses and doctors, who were working around all of the blood work and testing and that kind of thing. It was really emotional just to see how scared and sad everybody looked. I guess I just hadn't thought about what it would be like to see these healthcare workers in their environment right now."
After 15 minutes of waiting in a near-empty room, a nurse took two vials of DeMellier's blood for testing.
DeMellier had nowhere near enough antibodies to donate
Antibodies are measured by taking a small amount of person's blood, creating a serum with it, and seeing how many antibodies are concentrated into that serum.
DeMellier was told that if her tested sample came back with fewer than 1:320 COVID-19 antibodies, they wouldn't be able to use her plasma in the trial. It came back with 1:150 antibodies.
What does that mean for DeMellier? She's technically not allowed to take this as a "diagnosis" because the FDA has not approved Mount Sinai's measuring system to test patients; it's only to use in a research context, Reich said.
"Most people are saying that a titer of 1:320 or stronger is optimal for a convalescent plasma [to treat COVID-19 patients]," Reich said. "So somewhere around 90% of the people that we tested have antibodies, have high concentrations of antibodies greater than that 1:320 threshold. But I'll mention that that's more in a research context, not in the FDA testing context."
Her doctors aren't sure why she doesn't have enough
A few days following her donation appointment, DeMellier received an email from Mount Sinai saying her antibody levels could rise in the coming weeks, making her blood viable for use. But the doctors could not say whether she has any kind of immunity just yet.
"It says that my body may not have had enough time yet to develop enough antibodies, and that I can try to follow up with my primary care physician in three weeks to see if they are able to retest for antibodies at that time," DeMellier said.
Reich said it's possible this could be the case for DeMellier and others who have lower antibody counts.
"They might come back a week later and the antibody levels might be higher. But you would expect, as with anything else in medicine, that there is probably a variable response that people's bodies have to this virus," he said. "And it's unclear if it has anything to do with severity of disease or other factors because it's just way too soon in the history of this disease to have figured that out."
Health experts don't know if all recovered COVID-19 patients will be immune — and how long immunity lasts
Researchers are still studying how COVID-19 immunity could work, and though they hope recovered patients won't be able to get sick again, they don't know for sure.
"What we hope is, if you get it once, you'll be protected against it for at least a year. We don't know that, but that's what we hope," Elizabeth Halloran, a biostatistician at Fred Hutchinson Cancer Research Center and University of Washington, told Business Insider. "We hope that a vaccine could induce an immunity that will keep people at least from dying. The immunity is still under research and it's got some potential bad qualities, but we don't know for sure."
On April 8, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said people who already had the coronavirus are unlikely to get sick again in the near future. At the same time, Fauci said it's difficult to tell how long a formerly sick person's immunity could last because the virus has the potential, albeit small, to mutate.
"If we get infected in February and March and recover, next September, October, that person who's infected — I believe — is going to be protected," Fauci said during a livestreamed conversation with Howard Bauchner, editor of the Journal of the American Medical Association.
'I'm treating it like I can definitely get sick again'
DeMellier said she's been staying home as much as possible and practicing social distancing while running errands because she doesn't want to get sick again.
"I'm treating it like I can definitely get sick again," DeMellier said. "I'm really limiting my time outside. I go for like one good run a day and if I need to run errands, I try and just do it all in one shot and I clean everything.
She said that her antibody test results make her feel like she doesn't have enough to be protected from reinfection.
"I'm not banking on that I can't get sick again. I was also a kid who had chicken pox twice, so..." DeMellier said.
Reich said it's still too early to know what blood antibody levels mean for immunity against the virus.
"There is a presumption that the higher the number of antibodies in the bloodstream, the more likely it is to quote unquote neutralize virus in the bloodstream," he said. "But remember this is primarily a respiratory virus. That's how people get infected. And so it's unclear what it means to have immunity in the bloodstream."
Read the original article on Business Insider