By Michelle Healy, USA TODAY
Thanks to the Internet, women who produce an abundant supply of breast milk and those in need of it for their babies have more opportunities than ever to connect. But a first-of-its-kind study finds high levels of harmful bacteria and contamination in breast milk purchased via the Web.
Researchers' analysis of 100 samples of breast milk bought on a public milk-sharing website found three in four samples contained either high levels of bacterial growth overall or contained disease-causing bacteria, including fecal contamination.
The findings were likely the result of poor hygiene during milk collection, the use of either unclean containers or unsanitary breast milk pump parts, or compromised shipping practices, says epidemiologist Sarah Keim, lead author of the study in November's Pediatrics, published online today.
Nineteen percent of sellers did not include dry ice or another cooling method when shipping, according to the study.
It is unknown exactly how common purchasing breast milk online is, but a soon-to-be published journal article by Keim found 13,000 postings on U.S. milk sharing websites in 2011.
It is "totally normal" for there to be certain bacteria in human breast milk, says Keim, a principal investigator with the Center for Biobehavioral Health at Nationwide Children's Hospital in Columbus, Ohio. Some are "very important and healthy for babies and the development of their immune system and digestive system," she says.
This study focused on bacteria which "are generally pretty harmless as long as they don't grow out of control" but have also been associated with illnesses in infants linked to contaminated milk, including staphylococcus and streptococcus, says Keim. It also focused on bacteria associated with disease even at low levels, such as salmonella and E. coli.
Researchers compared the online-purchased breast milk samples to samples of unpasteurized breast milk donated to a non-profit milk bank.
Twelve such banks throughout the U.S. follow strict guidelines set by the Human Milk Banking Association of North America and provide pasteurized milk from carefully screened donors to fragile and premature infants, primarily in hospitals. Pasteurization kills the harmful bacteria before the milk reaches an infant.
In all the samples analyzed, the Web-purchased milk had higher bacteria counts and were more likely to contain disease-related types of bacteria, even though the donated milk from the milk banks had yet to be pasteurized:
-- 72% had any detectable gram-negative bacteria, which are associated with bloodstream infections, wound or surgical site infections, meningitis and fecal contamination vs. 35% of milk bank samples
-- 63% tested positive for staphylococcus vs. 25% of milk bank samples
-- 36% tested positive for streptococcus vs. 4% of milk bank samples
-- 3% were contaminated with salmonella vs. none of the milk bank samples.
All of the samples tested negative for HIV, says Keim, but the laboratory analysis to determine "the authenticity" of the breast milk is just beginning, she says, adding: "We're a little suspicious of some of the milk."
"This study confirms what people have suspected in terms of online milk purchases," says Anne Eglash, a family medicine physician with University of Wisconsin Health in Mt. Horeb and a co-founder of the Academy of Breastfeeding Medicine. She was not involved in the new study.
"You don't know what you're getting, you don't know the quality, how honest people are about how old the milk is, and so many other issues. It's important to realize that this may not be the safest way to get breast milk when you don't have enough," she says.
But Eglash, co-medical director of the still-in-development Mother's Milk Bank of the Western Great Lakes, cautions against "throwing the baby out with the bathwater" when it comes to the sharing of raw, unpasteurized human breast milk between lactating women and those who cannot, for medical or other reasons, provide their own milk for their healthy, full-term babies.
"I don't think the message should be that women should never share milk, but that this behavior of buying it on the Web from someone you don't know should not happen," she says. Eglash emphasizes that "you don't want unpasteurized milk that has various bacteria going to an infant whose immune system is vulnerable," but says there are safe ways to share human breast milk with healthy infants who are not your own, as well as pasteurize it at home.
The Food and Drug Administration warns against feeding babies breast milk acquired directly from individuals or through the Internet, citing safety concerns; the American Academy of Pediatrics discourages feeding preterm infants human breast milk from unscreened donors.
Keim, author of the new study, says her findings "may not apply to situations where milk is shared among friends or relatives or donated rather than sold. The potential risks of those situations are less well understood."