A raw milk cheese tied to an E. coli outbreak has sickened 13 people in 9 states

An E. coli outbreak tied to raw milk cheese has sickened 13 people across nine states, with 8 hospitalized and three left with a life-threatening kidney complication called hemolytic uremic syndrome, according to the Centers for Disease Control and Prevention. Whole genome sequencing has linked the illnesses to Graziers-brand cheese made by Sierra Nevada Cheese Company. More than half of the sick are children age 5 or younger.

Whole genome sequencing ties 13 cases to one cheese

Investigators used whole genome sequencing to compare bacterial samples from every confirmed patient, a DNA-fingerprinting method that showed the strains were closely related enough to share a single source. The CDC’s PulseNet system, the national database that flags most multistate foodborne outbreaks, matched the cases as illnesses were reported with onset dates between July 7 and Aug. 26.

As of Sept. 25, the CDC counted 13 lab-confirmed illnesses, 8 hospitalizations and 3 cases of hemolytic uremic syndrome, the kidney complication that can follow a severe E. coli infection; no deaths have been reported. Every patient interviewed said they had eaten the implicated cheese in the week before falling ill, and the bacteria isolated from their samples were a genetically close match, according to the agency’s investigation notes.

The outbreak strain, E. coli O26:H11, is a Shiga toxin-producing bacterium in the same family as the O157 strain behind most large ground-beef recalls, but it is harder for many commercial labs to catch because it does not always trigger the standard O157-specific screening test used in routine stool testing. Public health labs typically need a separate Shiga-toxin assay or genetic sequencing to identify it, which is part of why case counts in outbreaks like this one tend to keep climbing for weeks after the first illnesses are reported rather than settling immediately.

Nine states, from California to Kentucky

The nine states with confirmed cases are California, Nevada, Colorado, Georgia, Kentucky, Michigan, Oregon, Tennessee and Utah, according to the FDA’s outbreak investigation page. California and Nevada each account for three of the 13 illnesses, the outbreak’s largest clusters, while the remaining seven states have one confirmed case apiece, per a state-by-state breakdown published by the food-safety law firm Marler Blog.

Sierra Nevada Cheese Company sold the recalled Graziers cheeses nationwide, in stores and online, in 8-ounce and 16-ounce retail packages as well as 5-pound loaves distributed to restaurants, delis and wholesalers that sometimes repackaged the cheese under their own store labels.

Raw milk cheese is legal to sell nationwide, but federal rules generally require aging it at least 60 days before sale, a step meant to let naturally occurring acids and competing bacteria reduce pathogen levels without the heat of pasteurization. That aging window lowers risk without eliminating it, which is why outbreaks tied to raw milk dairy products have recurred periodically even at facilities that meet the aging requirement, and why regulators keep raw milk cheese under closer routine scrutiny than pasteurized varieties.

Children under 5 make up most of the sick

More than half of the people sickened in this outbreak are children age 5 or younger, the CDC says. Young children are especially vulnerable to severe E. coli infection because their kidneys are less able to clear the toxin the bacteria release, part of why hemolytic uremic syndrome disproportionately strikes kids in outbreaks tied to raw dairy and undercooked beef alike.

“Do not eat recalled Graziers raw milk cheeses produced by Sierra Nevada Cheese Company,” the CDC said in its guidance to consumers, adding that shoppers should check refrigerators and freezers for any of the recalled products and throw them out or return them for a refund.

Hemolytic uremic syndrome develops when the Shiga toxin damages the lining of small blood vessels, a process that can shut down the kidneys and, in the most severe cases, require dialysis. Doctors generally avoid antibiotics when treating Shiga toxin-producing infections, since killing the bacteria can release more toxin into the bloodstream and worsen the syndrome rather than resolve it; supportive care such as fluids and close monitoring is the standard approach instead.

Graziers cheese’s long shelf life complicates the recall

Sierra Nevada Cheese Company agreed to recall the Graziers line on Sept. 24, the same day the FDA notified the company of the outbreak link. The product’s long shelf life means packages sold weeks or months ago could still be sitting unopened in home refrigerators or freezers, which is why both agencies are repeating the disposal warning rather than assuming the recall alone will clear shelves and kitchens.

The CDC has cautioned that the outbreak may not be limited to the states with illnesses confirmed so far, since cases can take weeks to be reported and matched through PulseNet. The investigation remains open, and the agency says the true toll could still grow as illnesses with onset dates near the Aug. 26 cutoff are confirmed through the same sequencing process that already linked the first 13 cases.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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