New moms who've recovered from the coronavirus appear to have a 'strong immune response' to the disease in their breast milk

• Rebecca Powell, a human milk immunologist in New York City, is collecting and studying breast milk samples from lactating women, including those who may have been exposed to COVID-19.
• Her preliminary findings suggest "there is a strong COVID-19 immune response" in new moms who've been infected.
• Her team hopes the pilot data will lead to more research that can answer whether breast milk helps protect babies from the disease, and whether components of the milk can help lead to a coronavirus treatment.
• Breast milk antibodies may have advantages over the more commonly studied blood antibodies, but are less studied.
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When she's not working from home or caring for her three kids (including breastfeeding one of them), Rebecca Powell finds time to put on a mask and trek across New York City to pick up breast milk from lactating women.

On at least one day, she crossed three boroughs for a collection. In a Facebook post, she said it was a testament to the lengths she'll go to get milk from a mom who's had a positive COVID-19 test.

Like food delivery these days, the milk collections are contactless.

Powell is an assistant professor of medicine and infectious diseases at Mount Sinai's Icahn School of Medicine who studies the immune properties of human breast milk.

Her lab is hoping to pin down whether breast milk has antibodies specific to COVID-19, whether they might protect babies from COVID-19, and ultimately, whether they can be spun into a therapy against the illness for adults.

Their early results are encouraging.

A NYC lab was studying flu antibodies in breast milk before the coronavirus hit

Antibodies are proteins created by the immune system to neutralize invaders like bacteria and viruses. In some cases, they can be used therapeutically, like for certain cancers or even to treat rabies in humans.

Scientists have been studying those that respond to COVID-19 in blood for both testing and treatment purposes, but less attention has been paid to their power in human milk.

But Powell was in a position to pay attention. Her lab, like others, had shown that there's "a really strong antibody in milk against flu," and was looking to learn more about how it did or didn't protect infants after moms were vaccinated.

Then the coronavirus struck.

"It seemed obvious to me that everything we don't know about flu is a million times more unknown and relevant about COVID-19," Powell said. "I immediately felt the urgency to initiate a study."

Preliminary work shows breast milk has a 'strong immune response' to COVID-19 in most recovered patients

The preliminary data from that pilot is slated to be published online this week. In it, her team analyzed 15 breast milk samples from women who've recovered from COVID-19 and 10 negative-COVID-19 samples taken from women before December 2019.

The team found that 80%, or 13, of the COVID-19 survivors had an antibody in their breast milk specific to the illness. The antibody was in "the most dominant class" of milk antibodies called immunoglobulin A (IgA).

"Overall, these data indicate that there is strong COVID-19 immune response in the milk after infection in the majority of individuals," Powell said.

While the findings don't mean the antibody can protect against COVID-19 in babies or in a therapy for adults, it does mean there's good reason for researchers to explore it, Powell argues.

"What I can do with this will depend on the funding I'm given," she said.

Breast milk may be understudied due to taboos

Some breast milk antibodies are well-known to help protect babies from various diseases like measles while they're too young to receive a vaccine, and breastfeeding is also associated with a lower risk of conditions including some gastrointestinal conditions, diabetes, asthma, and sudden infant death syndrome.

That's a large reason why organizations including the Centers for Disease Control and Prevention recommend the practice, even when moms have COVID-19 since there's no evidence they can pass it on through breast milk.

Despite its known immunological power, the substance is understudied, especially when compared to blood antibodies.

But breast milk antibodies may have an advantage in that they come in the IgA form which are "designed to not fall apart when it's in the baby's mouth or stomach," Powell said. "It's quite durable."

In other words, the structure of the antibodies may allow them to hold up especially well if used therapeutically, like through an IV.

Powell, who's also a lactation specialist, suspects the gap in breast milk antibody research is due to the taboo nature of breastfeeding in the US. The CDC recommends exclusively breastfeeding a newborn for six months. But less than half of babies in the US are breastfed through even three months. Many women initiate breastfeeding, but without mandated paid leave, and other barriers, many mothers struggle to continue.

"I don't think people look to [breastfeeding] as an important thing because, absolutely, in this country you can choose to feed your baby however you want, and it's totally fine," Powell said.

It also can be difficult to study and collect human milk, and there's no single governing body to oversee those processes. As a breastfeeding mom who's well-connected to other lactating moms in the community, though, Powell has been able to leverage her personal relationships to collect milk and has found donors on social media.

So far, she's personally collected about 25 1-ounce samples from new moms who had the illness and have recovered. The team also has about 1,500 people, including 400 people who have already been infected, nationally signed up to participate.

We're still many steps away from a breast milk-inspired treatment

While there's good reason to be hopeful about breast milk as a key player in the bigger coronavirus treatment picture, researchers, including Powell, are many steps and funding dollars away from developing an effective therapy.

Dr. Kirsi M. Jarvinen-Seppo, the chief of pediatric allergy and immunology at the University of Rochester Medical Center, is also collecting breast milk samples in her area to test for both the presence of COVID-19 and antibodies against it.

"This has to be thoroughly researched first to know that the harm is bigger than the benefit," Jarvinen-Seppo said.

No matter how it pans out, Powell said simply collecting milk samples during this pandemic can yield important epidemiological information in the future, aid researchers developing vaccines, and fill in important gaps breast milk research. Those broader benefits coming out of a time of social isolation, she said, is "the beauty" of her work.

Women interested in participating in Powell's research can email COVID19HumanMilkStudy@gmail.com and those closer to Rochester, New York, should contact rita_ferri@urmc.rochester.edu to inquire about participating in Jarvinen-Seppo's work.