Multiple locus variable number tandem repeat analysis of Acinetobacter baumannii strains isolated from human clinical and animal meat samples

Abstract

The current research was done to study the prevalence rate and molecular typing of Acinetobacter baumannii strains isolated from human and animal samples. One-hundred and seventy-four animal meat and 128 human clinical samples were collected and subjected to bacterial culture. A. baumannii isolates were confirmed using the Loop-mediated isothermal amplification. Approved strains were subjected to molecular typing using the multiple-locus variable number tandem repeat analysis method. Forty-four out of 174 (25.28%) raw meat and 64 out of 128 (50%) human samples were positive for A. baumannii strains. Ovine meat (39.28%) and urine (56.06%) samples had the highest prevalence of A. baumannii strains. Eighteen human isolates were located in eight separate profiles, whereas 18 animal isolates were located in six separate profiles. The highest similarities were found between human-based A. baumannii isolates nos 6, 7 and 18 with isolates nos 5, 11, 13 and 15 (85.6% similarity). The highest similarities were found between animal-based A. baumannii isolates nos 10, 11 and 17 (99.8% similarity). From a total of 10 studied variable copy numbers of tandem repeats (VNTR) loci, 0845, 0826 and 3406 were detected in all animal-based A. baumannii isolates. Moreover, 3406 VNTR loci was only detected in all 18 human-based A. baumannii isolates. A. baumannii isolate no 17 (harbored all 10 VNTR loci) and A. baumannii isolates nos 6, 7 and 18 (harbored 9 VNTR loci) were the most pathogenic human and animal-based strains. Multiple-locus variable number tandem repeat analysis was considered as an accurate and practical method for molecular typing of A. baumannii strains.