Virulence factors and antibiotic resistance in Staphylococcus aureus and Clostridium perfringens from landfill leachate

Abstract

A total of 34 isolates of bacteria, 20 Staphylococus aureus and 14 Clostridium perfringensfrom leachate samples, were investigated for virulence factors and antibiotic resistance. Majority (>70%) of the isolates produced enterotoxins. Many of the S. aureus isolates tested positive for deoxyribonuclease, haemolysins and slime production. Staphylococcal enterotoxin A (SEA) was the predominant enterotoxin produced by the S. aureus. None of the S. aureus was resistant to ciprofloxacin, novobiocin and vancomycin. Six isolates were resistant to methicillin and majority of them were resistant to penicillin, ampicillin and bacitracin. Eleven (78.6%) of the C. perfringens isolates produced enterotoxin and were also beta haemolytic. Except for one strain each of C. perfringens which were resistant to penicillin and ampicillin-sulbaltam respectively, all others were susceptible to the antibiotics tested. The presence of several of the virulence traits investigated and resistance to commonly used antibiotics in many of the S. aureus and C. perfringenstested raises concern about their dissemination through leachate to the environment. The accumulation of leachate and possible contamination of surface and groundwater sources also points out its potential risk for public health. There is need for some measures to properly manage waste and consequently reduce surface and groundwater contamination through leachate percolation.   Key words: Virulence factor, landfill leachate, antibiotic resistance, Staphylococcus aureus, Clostridium perfringens, health impact.