Salmonella from breast milk!
Via the New York Times, a story to add to the list of things that have led to Salmonella outbreaks recently. A study published this week in the journal Pediatrics details a growing problem with breast milk sold or donated via websites that has been found to be contaminated with high levels of potentially pathogenic microorganisms. Researchers obtained 101 samples from a popular Internet milk-sharing website, as well as 20 samples of unpasteurized breast milk which had been donated to a more traditional local milk bank. Most of the Internet samples (74%) were contaminated with Gram negative bacteria, whereas 35% of the banked milk were contaminated. Additionally, contaminated Internet samples had at least 10-fold higher levels of bacteria in comparison to the banked samples. Internet samples were also contaminated with cytomegalovirus 20% of the time.
The authors conclude that the high level of contamination reflects the overall poor attention to “collection, storage, and shipping practices” with very fundamental lapses in aseptic technique. Although the websites typically prominently display collection criteria, because there is no oversight in the process, it is unclear what level of compliance is actually followed. Local milk bank resources on the other hand have strict guidelines, and the milk is pasteurized prior to distribution. Some advocates of the websites maintain that pasteurization itself diminishes the benefits of expressed breast milk relative to infant formula, however there doesn’t appear to be any concrete evidence that such benefits exist to use unpasteurized milk when pasteurization is easily accomplished. Comments in the Times article from Kim Updegrove, president of the milk-bank association, further underscore issues with these unregulated Internet sites, including the possibility that recipients might be getting cow’s milk or formula from an unknown Internet source.