Studies on Drug Resistance among Klebsiella and Citrobacter spp Isolated from two Human Groups and Wild Animals

The global threat of antimicrobial resistance is undoubtedly on the increase and most researches in this area have concentrated on effects of drug exposure and usage on resistance. Little attention has been given to natural environments apparently devoid of direct anthropogenic impact as possible reservoirs of drug resistance traits.
This research was undertaken to determine possible similarities between drug resistance traits in species of Klebsiella and Citrobacter obtained from wild animals and 2 human groups.
Human samples were collected from Humans free from antibiotics (HN) and Human on antibiotics (HA) while samples from wildlife (WL) were taken from rats (Rattus spp), grasscutters (Thryonomys swinderianus), squirrels (Xerus erythropus), antelopes (Tragelephus scriptus), rabbits (Oryctolagus cuniculus), and farm lizards (Agama spp). Samples were analyzed using basic microbiological methods. The Disc diffusion technique was used for drug sensitivity testing while plasmid analysis was based on gel electrophoresis.
Members of the genus Klebsiella isolated from HA exhibited more resistance to ampicillin (AMP) and augmentin (AUG) than those isolated from HN. However, Klebsiella isolated from HN displayed higher resistance to ceftriaxone (CTN), clarithromycin (CMN), ofloxacin (OFL), and pefloxacin (PEF) than those from HA. WL isolates were mostly resistant to AMP, CMN, and AUG, and less resistant to PEF, CTN, and ciprofloxacin. Correlation analysis of the antimicrobial resistance pattern on a 2 tailed test P ≤ 0.01 and P ≤ 0.05, revealed a high correlation (ranging from 0.715 to 0.917) among all the microorganisms from both sources. Gel electrophoretic analysis of plasmid DNA extracted from the isolates revealed the presence of a 23.1 kb plasmid DNA in 6 strains of Citrobacter and 3 strains of Klebsiella.
These results indicate that wild life may be important reservoirs of drug resistance genes and pathogens that have public health relevance.