Detection of mecA positive staphylococcal species in a wastewater treatment plant in South Africa

Environ Sci Pollut Res Int. 2023 Nov;30(55):117165-117178. doi: 10.1007/s11356-023-30319-9. Epub 2023 Oct 21.

Abstract

We investigated the prevalence of antibiotic resistant staphylococci and detection of resistant, virulence, and Spa genes in a South African wastewater treatment plant. Species identified were Staphylococcus aureus, S. lentus, S. arlettae, S. cohnii, S. haemolyticus, S. nepalensis, S. sciuri (now Mammaliicoccus sciuri), and S. xylosus. Isolates showed high resistance to methicillin (91%), ampicillin (89%), ciprofloxacin (86%), amoxycillin (80%), ceftazidime (74%), and cloxacillin (71%). Multiple antibiotic resistance (MAR) index for the isolates exceeded 0.2 (0.50-0.70). Among the isolates, 77% were mecA-positive. All S. aureus strains were positive for nuc and 7 Spa gene types. The present study highlights possibility of treated wastewaters being potential reservoir for antibiotic-resistant staphylococci. This is a cause for concern as wastewater effluents are decanted into environmental waters and these are, in many cases, used for various purposes including recreation (full contact), religious (full body submersion), and drinking water for some rural communities and water for livestock.

Keywords: Antibiotic resistance genes; Coagulase negative Staphylococci; Methicillin-resistant Staphylococcus aureus; Protein A gene (spa); Wastewater treatment plant; mecA gene.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Humans
  • Methicillin
  • Microbial Sensitivity Tests
  • South Africa
  • Staphylococcal Infections* / epidemiology
  • Staphylococcus aureus*

Substances

  • Anti-Bacterial Agents
  • Methicillin