Evidence of cross-contamination of waste workers and transmission of antimicrobial resistance genes by coagulase-negative Staphylococcus isolated from dental solid waste: an intriguing study

ABSTRACT

The aim of this study was to phenotypically and genotypically identify coagulase-negative Staphylococcus (CoNS) recovered from the nostrils of waste workers and from dental waste; 135 strains were recovered and S. epidermidis was the prevailing species. Genetic similarity (100%) was observed between the two S. epidermidis isolated from different employees on the same shift and 85% similarity between the S. epidermidis recovered from an employee’s nostril and from waste. The mecA gene was found in 20 CoNS, and 20% were also found to possess the vanA gene. The blaZ gene was detected in 46.7%, and the icaA (34.8%), B and C genes (11.8% each). Our findings emphasized the biological risk to which waste workers are exposed and unprecedently confirms that it was possible to recover genetically identical bacterial species from waste and from workers’ nostrils. It is important to highlight that this risk is raised by the detection of relevant antimicrobial resistance genes. The results also suggest that effective measures to correctly manage waste and promote the rational use of antimicrobials should be adopted.

KEYWORDS:

• Staphylococcus coagulase-negative
• dental solid waste
• waste workers
• healthcare dental service
• maldi-TOF

Acknoledgements

This work was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq, Fundação de Amparo à Pesquisa do Estado de Minas Gerais – FAPEMIG (Process #APQ-03459-13) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior- CAPES.

Disclosure of Interest

The authors report no conflict of interest.

Additional information

Funding

This work was supported by the Conselho Nacional de Desenvolvimento Científico e Tecnológico; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; Fundação de Amparo à Pesquisa do Estado de Minas Gerais [Process #APQ-03459-13].