High Throughput Multiple Locus Variable Number of Tandem Repeat Analysis (MLVA) of Staphylococcus aureus from Human, Animal and Food Sources

Abstract

Staphylococcus aureus is a major human pathogen, a relevant pathogen in veterinary medicine, and a major cause of food poisoning. Epidemiological investigation tools are needed to establish surveillance of S. aureus strains in humans, animals and food. In this study, we investigated 145 S. aureus isolates recovered from various animal species, disease conditions, food products and food poisoning events. Multiple Locus Variable Number of Tandem Repeat (VNTR) analysis (MLVA), known to be highly efficient for the genotyping of human S. aureus isolates, was used and shown to be equally well suited for the typing of animal S. aureus isolates. MLVA was improved by using sixteen VNTR loci amplified in two multiplex PCRs and analyzed by capillary electrophoresis ensuring a high throughput and high discriminatory power. The isolates were assigned to twelve known clonal complexes (CCs) and –a few singletons. Half of the test collection belonged to four CCs (CC9, CC97, CC133, CC398) previously described as mostly associated with animals. The remaining eight CCs (CC1, CC5, CC8, CC15, CC25, CC30, CC45, CC51), representing 46% of the animal isolates, are common in humans. Interestingly, isolates responsible for food poisoning show a CC distribution signature typical of human isolates and strikingly different from animal isolates, suggesting a predominantly human origin.

Development of a Multiple-Locus Variable-Number Tandem-Repeat Typing Scheme for Genetic Fingerprinting of Burkholderia cenocepacia and Application to Nationwide Epidemiological Analysis

“…Besides, the MLVA-10 scheme could easily be automated using fluorescent primers and a single multiplex PCR (31). Capillary electrophoresis would allow automatic size measurement of the PCR products and thus increase the accuracy of repeat number determination, as described for other bacterial species (31)(32)(33). Furthermore, some potentially informative VNTR markers that were ruled out from the present scheme due to short repeats (Ͻ15 bp) could be included to constitute a second panel with high discriminatory power, as has been proposed for other bacteria (34).…”

Antibiotics usage in food-producing animals in South Africa and impact on human: Antibiotic resistance

“…It is suggested that livestock associated MRSA originally were methicillin-susceptible commensal strains in pigs, whose spread was facilitated by the abundant use of antibiotics in pig and cattle farming (Voss et al, 2005). S. aureus is a major human pathogen, a relevant pathogen in veterinary medicine, and a major cause of food poisoning (Sobral et al, 2012). A joint ECDC/EFSA/EMA (2009) scientific report demonstrated that pigs are a major reservoir of a new emerging type of MRSA and concluded that the extensive use of antibiotics for prevention of disease appears to be an important risk factor for the spread of MRSA.…”

Capillary electrophoresis based on nucleic acid detection for diagnosing human infectious disease

“…Thus, epidemiological approaches monitoring S. aureus strains need to be established. Therefore, Sobral et al [23] developed an MLVA-CE method exploiting 16 VNTR loci amplified in two multiplex PCRs with analyzed PCR products using CE to genotype human S. aureus isolates in a highly efficient and discriminating manner. Du et al [24] developed and evaluated an improved multilocus VNTR fingerprinting using CGE for detection (CGE-MLVF), which replaced AGE (traditional MLVF) with CGE.…”