The US CDC is reporting an outbreak of salmonellosis linked to dry dog food. It’s a small outbreak in terms of the number of diagnosed infections (7) but, as always, the diagnosed infections are presumably just the tip of the iceberg, especially since they have been found in seven different US states (see map below).

• The outbreak strain is a strain of Salmonella Kiambu
• Cases to date were identified between January 14 and August 19, 2023.
• Six of the seven infected people were infants.
• One patient was hospitalized, none died.

Five household investigations occurred and dogs were present in all households. Three reported feeding their dog a specific brand of dry dog food, Victor HiPro Plus.

The outbreak strain of Salmonella Kiambu was also found in a sample of this same dog food that was collected at a retail source in South Carolina. It sounds like that sample might have been part of a separate routine surveillance program, since no human cases were reported in that state. No food from affected households was available for testing because by the time the problem was identified, the offending food was long gone (as is often the case).

Regardless, there was a strong link to a specific lot of of that dog food, since CDC didn’t hedge the wording: “a specific lot of Victor brand Hi-Pro Plus dry dog food is contaminated with Salmonella and has made people sick.”

The implicated dog food, as well as other brands of dog and cat food produced at the same facility, has been recalled by the manufacturer. However, it took some time to trigger the recall. On September 3, they recalled one specific lot of the dog food. Then on October 30, they recalled some other lots. Finally, on November 9, they recalled all brands made at the facility. Presumably they identified issues with ongoing contamination or other significant deficiencies at the plant, so they expanded the recall.

Raw diets for pets get most of the attention with respect to Salmonella risks. That’s fair because they are much higher risk for contamination, and there have been numerous cases and outbreaks linked to them (including one currently under investigation in Canada). However, dry diets also pose some risk; contamination in these cases is usually linked to poor manufacturing practices. While we rarely have contamination issues with dry diets, given the volume of dry food that can be produced by a facility, when contamination does happen it can be a big (and very widespread) problem.

I’m not sure we’ll get much more information about how this happened, but we’ll see if more information comes out after the outbreak investigation is wrapped up. There may be new cases that have not yet been identified or infections that will develop from recalled food that’s still in households. Since there was such a delay in the final recall, presumably there’s a lot of this pet food in households in the US. Hopefully it was more of an “abundance of caution” recall of everything versus evidence of ongoing contamination of all that pet food, because if it was the latter, more infections are likely to happen.