Phylogeny of hospital acquired MRSA, and its comparative phenotypic clinico-epidemiology with vancomycin resistant S. aureus (VRSA)

Microb Pathog. 2020 Dec:149:104537. doi: 10.1016/j.micpath.2020.104537. Epub 2020 Sep 24.

Abstract

Staphylococcus aureus is emerging as complicated pathogen because of its wide-ranging origin, multiple variants, and compromised antibiotic susceptibilities. Current study was planned to find lineage of hospital acquired methicillin resistant Staphylococcus aureus (HA-MRSA), and its comparative phenotypic clinico-epidemiology with vancomycin resistant S. aureus (VRSA). A total of (n = 200) samples were aseptically collected from wound, nose, and cerebrospinal fluid of patients from metropolitan and rural background hospitals along with on spot filling in of questionnaire. Phylogenetic analysis of HA-MRSA was identified by targeting mecA gene in S. aureus. At optimal tree branch length of 1.91 and evolutionary distance 0.1, high level sequence similarity (97%-99%) was observed with different strains of S. aureus isolated from both human and animal. Non-descriptive statistics at 5% probability found 61% S. aureus, while 43.44% of them were HA-MRSA, 92.62% VRSA, and 42.62% were both MRSA and VRSA. Among assumed risk factors, use of antibiotics, venous catheterization, chronic disease, pre-hospital visits, and ICU admitted patients showed significant association (p<0.05) with pathogen. HA-MRSA was 37.50%, 80%, and 37.50% sensitive to chloramphenicol, gentamicin, and oxacillin, respectively. While <50% of VRSA were sensitive against oxacillin, enoxacin, and chloramphenicol. A significant difference (p<0.05) of percentage responses of MRSA and VRSA at resistant, intermediate, and sensitive cadre against all antibiotics except chloramphenicol was obvious in this study. The Current study concluded higher prevalence of MRSA & VRSA, significant association of risk factors, limiting antibiotic susceptibility profile, and genetic transfer at animal-human interface which suggests further studies cum preventive strategies to be planned.

Keywords: Antibiotic susceptibility assay; Epidemiology; HA-MRSA; Phylogeny; Risk factors; VRSA.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Anti-Bacterial Agents / therapeutic use
  • Cross Infection* / drug therapy
  • Hospitals
  • Humans
  • Methicillin-Resistant Staphylococcus aureus* / genetics
  • Microbial Sensitivity Tests
  • Phylogeny
  • Staphylococcal Infections* / drug therapy
  • Staphylococcal Infections* / epidemiology
  • Staphylococcus aureus / genetics
  • Vancomycin / pharmacology
  • Vancomycin-Resistant Staphylococcus aureus

Substances

  • Anti-Bacterial Agents
  • Vancomycin