High Levels of Drug-Resistant Bacteria Found in Raw Dog Food, Researchers Say

A dog is seen eating and drinking in a file photo. Patrick T. Fallon/AFP via Getty Images

High levels of potentially deadly and drug-resistant bacteria were found in uncooked meats for human consumption and raw dog food sold in stores, said researchers in the United Kingdom.

Researchers from the University of Bristol analyzed 58 samples of raw chicken, beef, pork, and lamb sold for human consumption at grocery stores in Bristol and 15 samples of chicken-based raw dog food from specialty pet stores. They found the presence of drug-resistant E. coli, and the samples were tested for resistance to a number of antibiotics such as amoxicillin, cefotaxime, ciprofloxacin, streptomycin, and spectinomycin, according to their pre-print study.

They found that 81 percent of the meat samples that were meant for human consumption tested positive for E. coli, while 87 percent of chicken-based raw dog food also tested positive for the bacteria.

“This study confirms that uncooked meat carries multiple resistant E. coli, commonly including resistance to critically important antibiotics important for human health,” the study authors said in a news release.

The release said that there is a “strong association between feeding dogs a diet of uncooked meat (raw dog food) and an increased risk of excreting E. coli resistant to critically important antibiotics in their feces,” adding that that “pet animals eating raw meat increases the risk of spreading resistant pathogens to their human owners in the household.”

Most consumers aren’t aware of the risk of the antibiotic-resistant bacteria present in such products, the authors said in their release.

“If ingested, these bacteria can enter the gut, and may cause resistant opportunistic infections (e.g. urinary tract infections) in the future,” the authors of the paper said. “It is therefore very important that people cook meat thoroughly before eating, and use appropriate hygiene practices during meat preparation. Our findings that raw dog food is similarly contaminated with resistant bacteria provides an explanation for why dogs fed raw meat are more likely to excrete these bacteria. Appropriate hygiene practices after handling raw dog food, and dogs that are fed such raw meat, are strongly advised.”

The University of Bristol-backed study was posted on a pre-print server. It has not yet been peer-reviewed.

Symptoms

Officials say that symptoms of E. coli in a dog is severe diarrhea, repeated vomiting, loss of appetite, is weak, collapsing, or is having difficulty breathing

In people, symptoms of certain forms of E. coli, or Escherichia coli, can cause stomach cramps, bloody diarrhea, and vomiting, according to health officials. Generally, healthy adults can recover from an infection in a matter of a few days, although younger children and the elderly are at a higher risk of developing more significant symptoms such as kidney failure.

Other than raw meat, some officials say that other ways to contract E. coli is via unpasteurized milk and fresh produce---notably certain vegetables like spinach and lettuce.

“E. coli bacteria can easily travel from person to person, especially when infected adults and children don’t wash their hands properly,” the Mayo Clinic says. “Family members of young children with E. coli infection are especially likely to get it themselves. Outbreaks have also occurred among children visiting petting zoos and in animal barns at county fairs.”

Riskier foods for E. coli include hamburger that isn’t well-cooked, unpasteurized milk, apple juice or cider, and soft cheeses made from raw milk, according to the clinic.

There is no vaccine or medication that can prevent an E. coli infection, according to the clinic, which advises people to cook ground beef until it’s 160 degrees F.

“Washing produce may not get rid of all E. coli — especially in leafy greens, which provide many places for the bacteria to attach themselves to. Careful rinsing can remove dirt and reduce the amount of bacteria that may be clinging to the produce,” the Mayo Clinic adds.