Three different bacteria were found in different dog food products. One is associated with kidney failure and neurologic issues in humans.
Photo: Jnis/Adobe Stock
Health officials with the FDA are cautioning pet owners against feeding their dogs certain lots of Darwin’s Natural Pet Products after detecting Escherichia coli and Salmonella contamination. Specifically, Darwin’s Natural Pet Products beef dog food tested positive for a particular strain of Escherichia coli (E. coli O157:H7) and one sample of Darwin’s chicken dog food tested positive for Salmonella Infantis. Additionally, one sample of Darwin’s duck dog food was found to be positive for Salmonella Hadar.1
E. coli O157:H7 produces toxins associated with damage to the intestinal lining, kidneys, or nervous system in humans. One way humans can become infected is through close contact with infected animals. Asymptomatic pets can still transmit the infection to humans by shedding the bacteria during bowel movements.
According to the FDA, certain E. coli O157:H7 infections in humans can lead to severe, bloody diarrhea and can result in life-threatening conditions such as chronic kidney disease, neurologic problems, high blood pressure, and hemolytic uremic syndrome (HUS)—a form of kidney failure.1
In cats and dogs, symptoms of the infection are usually milder than in humans. These animals may experience watery and/or bloody diarrhea, urinary tract infections, and vomiting. In pets with a weakened immune system, symptoms may be more severe. Although the infection is rarely fatal in pets, there have been reports of dogs that have died from the illness.1
Salmonella, meanwhile, can cause illness and death in both humans and animals. In humans, symptoms may include diarrhea, fever, and abdominal cramps. Although most recover, in people with severe infections, such as those who are very young, very old, or immunocompromised, the infection can spread from the intestines to the blood stream and to other parts of the body without quick intervention.
Although not all pets will exhibit signs of Salmonella infection, symptoms can include vomiting, diarrhea, fever, loss of appetite, and decreased activity level. Some pets may be carriers of the disease and show no symptoms of infection.
Additionally, the CDC classifies the Salmonella Hadar strain as a “persistent strain,”2 while Salmonella Infantis, which is common in poultry, has been posing a growing public health concern. According to a 2023 study, Salmonella Infantis has been found to be multidrug-resistant.3
In August 2024, a 4-year-old child contracted E. coli O157:H7 and developed HUS. The child, according to the FDA, was subsequently hospitalized and required extensive follow-up care.1
Complaint information submitted to the federal agency reported the child having direct contact with a family dog whose diet only consisted of Darwin’s pet food. The dog began vomiting one day before the child became ill, with the dog’s condition resolving without veterinary care, according to the report.1
Closed packages of unopened Darwin’s beef dog food from the family’s household freezer were later tested in May and June 2025 via whole genome sequencing by a third-party laboratory and were found to be a genetic match to the E. coli O157:H7 strain found in the child’s stool sample.1
The child had no known direct contact with the contaminated food, leading health officials to suspect the child was exposed to the bacteria through contact with the dog or objects or surfaces contaminated with the dog’s feces.1
Additionally, 2 more Darwin’s products from the family’s freezer tested positive for Salmonella Infantis and Salmonella Hadar.
“Because this incident occurred in 2024, there were no retail samples available for collection and testing when the complaint information and private laboratory results were submitted to the FDA in June 2025,” wrote the FDA in its announcement.1 “Additionally, Darwin’s Natural Pet Products does not have samples from the same product lot available for additional testing. Therefore, the FDA reviewed the results of the third-party testing conducted by the lab, which is accredited by the FDA Laboratory Accreditation for Analyses of Foods program.”
To date, Arrow Reliance Inc, the producer of the Darwin’s products, has not recalled the affected product lots despite recommendations from the FDA.
“These products, which were manufactured in May or June 2024, were sold frozen, have no expiration date on the label, and could still be in consumers’ freezers. Therefore, the FDA advises consumers to check their freezers for the affected lots of Darwin’s Natural Pet Products prior to feeding to pets,” the federal agency said.1
All lots of the contaminated pet food were sold in frozen 2 lb white and clear plastic packages and consist of1:
Affected Darwin's dog food products. (Image courtesy of FDA)
Product lot codes can be found on the front and the lower left area of the package. Additionally, Labels on the beef and chicken BioLogics products are orange and the duck Natural Selections dog food has blue labels.
“If you have any of the lots of Darwin’s BioLogics or Natural Selections pet food products listed above, stop feeding the product to your pets and throw it away in a secure container where other animals, including wildlife, cannot access it,” stated the FDA in its announcement.1 “Do not donate the food...If you no longer have the package or can’t read the lot code, throw the food away.”
The agency advises pet owners who were in possession of the affected products to clean and disinfect all pet supplies and other surfaces the dog may have come into contact with. This includes cleaning up the dog’s stool in yards, parks, or other places where contamination may be possible.
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