Antibiotic Susceptibility of Zoonotic Bacteria Isolated From Oral Cavities of Indigenous Dogs From Semi-Urban Areas in Uganda.

Abstract

Dog bites are a source of zoonotic infections to humans, such as pasteurellosis and meningitis. Zoonotic bacterial identification and their antibiotic susceptibility assessment are key towards the successful management of such infections. This study isolated and identified zoonotic bacterial species from the oral cavities of indigenous dogs and also determined their antibiotic susceptibility profile. Oral swab samples collected from 54 indigenous dogs (domestic [36] and stray [18]) were cultured on agar media, and then on selective-differential media. The colony morphology and conventional biochemical tests were used to identify the bacterial isolates. Antibiotic susceptibility was evaluated using the Kirby-Bauer disk diffusion method. A total of 232 bacterial isolates were obtained, from which 29 bacteria species (18 Gram-negative and 11 Gram-positive) belonging to 19 genera and 13 families were identified. Aerobic and anaerobic bacteria species constituted 69% and 31%, respectively. The most prevalent bacteria species was Staphylococcus aureus (10.8%) followed by Escherichia coli (9.5%), while Yersinia enterocolitica (0.4%) was the least common. Most bacteria species belonged to family Enterobacteriaceae (11) followed by Vibrionaceae (04). All the sampled dogs had a number of multi-drug-resistant superbugs in their oral cavities. However, all the tested bacterial isolates were only susceptible to imipenem and chloramphenicol. All the identified bacteria species were resistant to metronidazole, amoxicillin-clavulanic acid and ceftazidime. Therefore, antibiotics such as imipenem and chloramphenicol could be of better choice for managing dog bite infections compared to the antibiotics recommended by Uganda Clinical Guidelines, such as metronidazole and amoxicillin-clavulanic acid.