Comparison of cockroach fungal contamination in the clinical and non-clinical environments from Iran

Cockroaches have been associated with human environments threatening human health. A cross-sectional study about cockroach fungal contamination in the hospital, restaurant and household environments from Khorramabad, Lorestan province of Iran between August 2015 and March 2016 was done. Sampling was uniformly carried out monthly from the randomly selected sites. Fungi were isolated from the external surfaces of cockroaches using standard method. Periplaneta americana (66.7%) was found the most infested cockroach, less percentage were observed in Blattella germanica (18.6%) and Blatta orientalis (14.7%). Hospitals (66.7%) were found the most infested places in comparison with households (18.6%) and restaurants (14.7%). Households (64.3%) were found the most cockroach fungal contaminated places than hospitals (49.0%) and restaurants (59.1%). The highest and the lowest infestation of cockroaches were observed in January (30.0%) and March (7.0%) respectively, while the highest and the lowest cockroach fungal contamination were observed in November (73.3%) and March (14.3%). B. germanica (60.7%) was the most fungal contaminated cockroach. Candida, Geotrichum and Penicillium were the most frequent cockroach fungal contaminating genera. Statistical analysis revealed significant differences between cockroach infestation places (P=0.022), locality (P=0.03), and monthly (P=0.0001) cockroach fungal contamination, respectively. As a conclusion, the highest cockroach fungal contamination was observed in B. germanica, followed by P. americana and B. orientalis. Some human fungal opportunistic pathogens were also found among the fungal contaminated cockroaches. Recent epidemiological survey showed that the mortality rates of the infective diseases were increased, indicating cockroaches involved in their transferring.