Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China.
Epidemiol Infect. 2012 Aug;140(8):1366-71. doi: 10.1017/S095026881100207X. Epub 2011 Oct 19.
Environmental staphylococcal contamination was investigated by culture of 400 automated teller machines (ATMs). Isolates were characterized for antibiotic and antiseptic susceptibility, carriage of antiseptic resistance genes (QAC genes), and spa types. MRSA, which was similar to local clinical isolates, was present on two (0·5%) of the 62 (15·5%) ATMs that yielded Staphylococcus aureus. QAC genes were more common in coagulase-negative staphylococci (qacA/B 26·0%, smr 14%) than S. aureus (11·3% qacA/B, 1·6% smr). QAC-positive isolates had significantly higher minimum inhibitory concentrations/minimum bactericidal concentrations to benzalkonium chloride and chlorhexidine digluconate. QAC gene presence was significantly associated with methicillin and tetracycline resistance. Survival of staphylococci, including MRSA, on common access sites may be facilitated by low disinfectant concentrations, which select for disinfectant-tolerant strains, while co-selecting for antibiotic-resistance determinants. Disinfection procedures should be performed correctly to help prevent spread of resistant pathogens from reservoirs in the community.
对 400 台自动取款机（ATM）进行了培养，以调查环境中葡萄球菌的污染情况。对分离株进行了抗生素和防腐剂敏感性、防腐剂耐药基因（QAC 基因）和 spa 型的特征分析。在 62 台（15.5%）产生金黄色葡萄球菌的 ATM 中有 2 台（0.5%）存在与当地临床分离株相似的耐甲氧西林金黄色葡萄球菌（MRSA）。凝固酶阴性葡萄球菌（qacA/B 26.0%，smr 14%）比金黄色葡萄球菌（qacA/B 11.3%，smr 1.6%）中更常见 QAC 基因。QAC 阳性分离株对苯扎氯铵和葡萄糖酸氯己定的最低抑菌浓度/最低杀菌浓度显著更高。QAC 基因的存在与耐甲氧西林和四环素耐药显著相关。包括 MRSA 在内的葡萄球菌在常见的接触部位存活，可能是由于消毒剂浓度较低所致，这会选择出耐受消毒剂的菌株，同时也会选择出抗生素耐药决定因素。应正确执行消毒程序，以帮助防止社区储源中耐药病原体的传播。
