German Cockroaches (Blattella Germanica L.) as a Potential Source of Pathogens Causing Nosocomial Infections

Abstract

German cockroaches collected in two hospitals were examined bacteriologically. Twenty strains of different taxons were isolated, all considered to be potentially pathogenic to humans. Some strains were resistant to antibacterial drugs widely used for treatment of patients: Gram-negative rods were resistant to amoxicillin/clavulanic acid, Pseudomonas spp. additionally resistant to co-trimoxasole. Strains of Staphylococcus equorum, S. hominis were methicillin-resistant, a strain of S. epidermidis showed MLSb mechanism of resistance. Determination of the minimum inhibitory concentration (MIC) for the disinfectant sodium dichloroisocyanurate showed it was in the range 500- 2000 mg. L−1. The MIC for glucoprotamine was from 1.453 to 500 mg. L−1. A strain of S. epidermidis was less sensitive (MIC = 125 mg. L−1) to glucoprotamine than other staphylococci, Serratia marcescens was resistant to that agent (MIC = 500 mg. L−1). Product containing glucoprotamine was ineffective against strains of S. epidermidis MLSb and Pseudomonas putida. Our data suggest that cockroaches might serve as a source of infection, by acting as carriers and reservoirs of bacterial strains in nosocomial outbreaks.