Researchers Note Tigecycline-Resistant Human Pathogens in Dogs

APRIL 11, 2017
Jennifer Barrett, Assistant Editor

Spanish researchers have documented the first example of tigecycline-resistant bacteria adapted to living on companion animals through a study that analyzed bacteria isolated from dogs at a veterinary hospital. The findings indicate wider implications for the spread of human pathogens resistant to a last-resort antibiotic.
The study was led by a research team from Complutense University in Spain and reported in Antimicrobial Agents and Chemotherapy, a journal of the American Society for Microbiology.
The researchers determined the presence of Klebsiella pneumoniae in the dogs, which researchers said likely had become tigecycline-resistant in a hospital setting. The researchers only found the bacteria’s resistance to antibiotics used against human pathogens after investigating resistance to veterinary antibiotics.
“These are human pathogens, which have become able to colonize dogs, and retain resistance to tigecycline,” Bruno Gonzalez-Zorn, DVM, PhD, professor of microbiology at the Veterinary School and Health Surveillance Center, VISAVET, said in a press release about the study.2 “They probably became resistant to tigecycline in the hospital environment, as these animals had not been treated with tigecycline.”
The findings suggest that tigecycline-resistant bacteria have been repeatedly introduced into hospitals, and raises concerns that the dog owners and those who had been in close contact with the dogs may be infected with these antibiotic-resistant pathogens.
In light of the results, whole genome sequencing is being conducted to determine which hospital the resistant K. pneumoniae came from. The researchers concluded that treating pet animals with antibiotics should be done carefully and minimally. 
1. Ovejero CM, Escudero JA, Thomas-Lopez D, et al. Klebsiella pneumoniae ST11 and ST147 high resistant to tigecycline from companion animals. Antimicrob Agents Chemother. 2017; doi: 10.1128/ACC.02640-16.
2. Resistance to antibiotic of last resort found in human pathogens infecting dogs [news release]. Washington, DC. ASM’s website. Accessed April 11, 2017.