An E. coli O26:H11 Outbreak Linked to Raw Milk Cheeses Leaves 13 Ill and Three Cases of Hemolytic Uremic Syndrome in the U.S.

The FDA and CDC announced on September 25 an investigation into an outbreak of Escherichia coli O26:H11 linked to cheeses made with raw milk from grass-fed cows by a U.S. producer. So far, 13 ill people have been counted in nine states (California, Colorado, Georgia, Kentucky, Michigan, Nevada, Oregon, Tennessee and Utah), of whom eight were hospitalized and three developed hemolytic uremic syndrome, with no deaths. According to the CDC, more than half of the ill are children five years old or younger. Of the nine people interviewed, all nine reported having eaten the recalled cheese.

After being notified by the FDA, the manufacturer began on September 24 a recall of its entire line of raw milk cheeses, in four varieties (mild cheddar, sharp cheddar, jalapeño jack-style and Monterey jack), in 8- and 16-ounce packages for retail sale and 5-pound blocks for wholesalers. The product was sold in stores across the country and online. The authorities asked consumers not to eat it, to throw it away and to wash with hot water and soap any surfaces that have been in contact with it, and recommended choosing pasteurized dairy products, especially for children under five.

E. coli O26 is one of the non-O157 serogroups of Shiga toxin-producing E. coli (STEC) that most frequently cause severe illness. In raw milk cheeses there is no pasteurization step to eliminate the pathogen if it arrives with the source milk, and aging alone does not guarantee its inactivation. The case also shows the weight of vulnerable groups: young children are the ones at greatest risk of developing hemolytic uremic syndrome, a complication that can permanently damage the kidneys.

For TAAG, the outbreak reinforces that STEC control in raw milk cheeses cannot be limited to looking for O157:H7: non-O157 serogroups such as O26 require methods targeting Shiga toxin genes, applied both to the raw milk entering the plant and to the cheese before release, since in this category there is no thermal barrier to compensate for contamination at the source.