Written by Erin Hamilton Spence, MD, IBCLC
Medical Director Mother’s Milk Bank of North Texas
Neonatologist, Fort Worth, TX

In March 2020, I was working in the NICU as my family was home on spring break. As my kids were sleeping in and staying up late, my inboxes filled with alarm bells about COVID-19. We modified our NICU by maximizing social distancing and conserving donor milk; not because of a shortage of donor milk, but to help secure the supply of donor milk to NICUs all over North America.

As medical director for a HMBANA milk bank as well as a frontline practicing neonatologist, I had one big question: Is donor milk still safe?

Specifically, is donor milk safe:

1) to feed fragile babies?

2) from a disrupted supply chain?

Could there be virus in the donated milk from healthy moms?

We screen donors in three key ways: the mother, her healthcare provider, and her milk. All of our mothers are “healthy women,” verified by the mom and her physician. But, what if a mother is asymptomatic? As more of our donating population gets exposed, the portion of asymptomatic carriers will rise. Fortunately, Chen et al give us hope that this virus HAS NOT been found in breastmilk of COVID+ mothers in a small retrospective cohort. But, what if this is not right enough? It’s a small sample size (n=6).

What if a larger sample of mothers would find the virus in breastmilk?

While they help us get information out quickly, retrospective cohorts, are notorious for both error and bias. While donor milk is safer than formula, especially for medically fragile babies at risk of NEC, donor milk is second best to mother’s own milk. Babies who receive donor milk are missing the feedback loop between mother and baby. Since infants on donor milk do not get the active immunity passed to infants during at-the-breast nursing, we are much more cautious about donor milk.

IF there is error or bias in this small study, how can we be 100% sure SARS-CoV-2 will be destroyed by our current pasteurization process?

The Human Milk Banking Association of North America (HMBANA) has responded to this question. Chin et al’s data about SARS-CoV-2 (supplementary tables) confirm COVID-19 is undetectable at 56°C for 30 minutes. HMBANA milk banks pasteurize milk at 62.5°C for 30 minutes (Holder pasteurization).

Is there ANY chance that a different media (ie breastmilk/donor milk) vs Chin’s viral culture media or a higher dose of virus would survive & be infective?

Since we have not been able to detect SARS-CoV-2 in breastmilk, it’s unclear if the virus could potentially persist if the sample were taken at a different time point, from more women, or at a higher dose, and if so, whether it could then potentially be infectious.

Viral dose – or inoculum – matters. To answer this final question, two US academic sites are performing a “spiked milk” protocol, similar to this one my team published in 2017 around the Ebola epidemic. For me, the results of these two parallel studies will confirm 100% that our donor milk supply is safe from containing the SARS-CoV-2 virus.

WHEW! So, the donor milk itself is almost certainly safe to feed to fragile babies.

What about the supply chain?

If our donors get sick – or just need to stay home – will we have enough donor milk for all the babies who need it?

Like the blood supply, the milk supply is subject to the health and accessibility of its donors. In North Texas, we initially chose to conserve our donor milk until our milk bank donor-relations team could intensify their recruitment efforts. Thankfully, their work paid off and we’ve been able to lift those initial limits on donor milk. The graph below shows monthly donations through April 14, 2020 (ounces). We’re so grateful to our donors! 

What about our staff? How can we keep them safe?

Milk bank staff have an increased risk of exposure. Of all the steps in the chain, the actual milk hand-off is in-person, of course. We’re providing at-home and drive-through lab draws with a phlebotomist in full PPE. Our milk bank driver and van have never been busier. These contactless donations have kept us running at full operating capacity in the midst of this crisis. Huge shout out to all the milk bank’s smart, tactical women leaders and workers securing milk for our most vulnerable babies, while keeping the milk and themselves safe.

What about the rest of the country? Do they have enough donor milk?

Our all-star team at the Mothers Milk Bank of North Texas in Fort Worth is led by our executive director, Amy Vickers, who currently serves as the president for HMBANA. We are committed to pursuing the best practices for all of our HMBANA milk banks and vulnerable infants across the country. Our team is invested in securing and sustaining the national donor milk supply. HMBANA leaders are constantly in touch (virtually) to ensure the availability of donor milk to regions hit hardest by COVID-19. The HMBANA board of directors provided this statement, and it echoes my experience:

“HMBANA collects weekly data to monitor donor recruitment during the COVID-19 pandemic. We are happy to report that donor recruitment has remained stable throughout this pandemic, and we are eternally grateful to all of the generous moms who donate their lifesaving gift of milk to non-profit HMBANA member milk banks.”

As I continue to care for infants and their mothers as a neonatologist, I leave my family at home – my husband and four kids. I wear scrubs, no jewelry, and a mask every day. During the past month, anxiety ebbs & flows. I’ve been losing more sleep than usual, but not over the questions I’ve outlined above. I am struggling to continue to connect with families who are worried about giving birth – all of whom are also overwhelmed – and donors and healthcare providers who are determined to make it through together. For all of us invested in preventing necrotizing enterocolitis, I am happy to report that donor milk remains safe. While this may be a moving target, we are nimble. We will respond, and we will stay safely apart until we can finally be together.