The emergence of bacteria that are resistant to antibiotics has increased worldwide in the past few decades. This is concerning because it limits the efficacy of these antibiotics to treat human diseases. Although the pharmaceutical industry has developed numerous new types of antibiotics since resistance was first detected after the Second World War, the situation today is that there are no antibiotic medications for which resistance has not been recorded.
According to the World Health Organization, we should all be doing our best to prevent the development of antibiotic resistance in bacteria, and a new study published in the Journal of Antimicrobial Chemotherapy suggests one way in which we can contribute to this.
The study, led by researchers from Bristol University, assessed the presence of drug-resistant Escherichia coli bacteria in the excrement of pet dogs in both rural and urban settings. E. coli are commonly associated with infections in humans and have also been shown previously to be shared between pet dogs and humans through everyday interactions.
For the investigation, the researchers collected and analyzed the feces of hundreds of dogs for the presence of E. coli that were resistant to antibiotics commonly used to treat human infections. Dog owners completed questionnaires about demographic factors and dog behavior and feeding regimes. All the dogs and owners were resident in a specified 50 x 50km study area in south-western England.
The researchers found a link between dogs that were fed raw meat and the presence of antibiotic resistant E. coli in their excrement. This link was stronger in the population of rural dogs than in those living in an urban setting. In urban dogs, however, there was an additional link between swimming in rivers and carrying resistant E. coli. The analysis also showed that rural dogs excreted resistant E. coli with specific genetic sequences that are also commonly found in the E. coli in cattle but not in humans in the region. Conversely, urban dogs carried resistant E. coli with genetic sequences commonly found in E. coli in humans, but not in cattle.
The research supports a recent study by the same team, published in the journal One Health, which looked at the presence of resistant E. coli in 16-week-old puppies. Both studies, which used data from different dogs, demonstrate that dogs may excrete resistant bacteria regardless of their age or the length of time they are fed a raw meat diet.
“Antibiotic-resistant bacteria are everywhere, but some antibiotics are considered critically important for use in humans,” said Professor Matthew Avison. “We have shown that dogs fed raw meat are more likely to carry bacteria resistant to these important medicines. This doesn’t mean that the animal, or the owner, will become sick.”
“E. coli is a widespread bacterium that is found in the intestines of all humans and animals, however it is a common cause of many diseases, including urinary tract infection, and can cause serious illness, including sepsis, if it spreads to other parts of the body.”
“We should do everything we can to reduce the circulation of critically important antibiotic-resistant E. coli and other bacteria. Our research adds to the increasing evidence that not feeding raw meat to dogs may help in that objective.”
“We know humans and animals share bacteria with one another, so what we find in your pet may well also be in you. Pet owners should be encouraged to practice good hygiene and not feeding raw food to your dog can be part of this,” added Professor Kristen Reyher. “We can all do our part to decrease antibiotic resistance and its terrible effects on both human and animal health.”