In Nejati’s study, nearly 75% of American cockroaches had at least one bacteria species on their external surface[3]. Results of Feizhaddah’s study showed that all the American cockroaches were positive for at least three bacteria[12]. In Kassiri’s study, Pathogenic bacteria were isolated from the external surfaces of 100% of the American cockroaches examined[11]. In Vahabi’s research, 74% of entrapped cockroaches had bacterial infection[1]. The separation of pathogenic bacterial agents from these domestic pests in hospitals and residential regions reveals that cockroaches can set health difficulties to people. Also, cockroaches with great rate of medically important bacteria may cause bacterial epidemic disease in hospitals. Furthermore, some individuals are allergic to their faeces particles. Thus, intervening procedures for control of cockroaches, such as Integrated Vector Management should be noticed.