Hospital and Ambulatory-Associated Animal Infections and Susceptibility to Antibiotics from 2019 to 2021

Abstract

Introduction: The only academic veterinary hospital and diagnostic laboratory in the State of Oregon receives samples for bacteriologic diagnosis and patients from the whole state and neighbor states. Infectious diseases diagnosed from 2019 to 2021 were evaluated for antimicrobial susceptibility by site of infection and isolated microbes. Methods: Bacteria were cultured and identified using standard laboratory methods. Antibiotic susceptibility was determined by using the Kirby-Bauer assay. Results: The analysis revealed the most common bacteria causing infection in diverse anatomic sites. The study also evaluated the percent of antibiotic susceptibility among the bacteria isolated. In 2019, a very common infection, such as peritonitis, the organisms isolated from the abdominal fluid were 66.7% susceptible to amikacin and 83% of them susceptible to enrofloxacin. In 2021, however, the organisms isolated from the abdominal fluid were susceptible to amikacin in 42.9% of the cases and 57.1 % susceptible to enrofloxacin. In urine infection 71% of the bacteria were susceptible to trimethoprim/sulfamethoxazole in 2019, 63.9% in 2020 and 65.7% in 2021. Some pathogens, like Enterobacter, were susceptible to amikacin in 58.8% of the cases in 2019, 50% in 2020 and 25% in 2021. Escherichia coli’s susceptibility to 3 rd generation cephalosporins was 65.4% to cefovecin and cefpodoxime, and 21.8% to ceftiofur in 2019, 68.4% and 75.4% to cefovecin and cefpodoxime and 7% ceftiofur in 2020, and 61.6%, 72.6% and 13.7% for the three antimicrobials in 2021. Of note is the low percent of susceptibility among pathogens isolated from many infectious sites, creating the need for veterinarians to make difficult decisions. Conclusion: The increased resistance of bacteria to antibiotics is now present in the veterinary world. The increased contact and interaction between animals and humans have extended the limited choice of antibiotics to treat infections in domestic animals, and therefore antibiotic stewardship programs must be implemented in veterinary practice.