Epidemiology and Spatial Relationships of Bacteria Associated with Periplaneta americana (Blattodea: Blattidae) in Central Texas

Identifying cockroach (Order: Blattodea) populations is important to understanding the ability of surrogate species indirectly affecting humans by their ability to vector disease-causing organisms including bacteria. These interactions may have potentially deleterious health consequences on animal and/or human populations. In this study, American cockroaches, Periplaneta americana were sampled from 12 locations throughout College Station, Texas from January through May 2008. Cockroach distribution was examined as well as prevalence of Escherichia coli including the O157:H7 strain and Campylobacter spp. on their external surfaces. Bacteria isolated from total populations collected indicated a high prevalence (92.3%) of microbes carried on the exoskeleton of P. americana. Gram-negative bacteria acquisition and dissemination of organisms such as E. coli was prevalent throughout the campus. Screening for E. coli O157:H7 and Campylobacter spp. resulted in no positive colony growth. The lack of Campylobacter spp. growth from cuticular surfaces may have resulted from undesirable conditions required to sustain colony growth. Data from this study corroborate the potential ability of cockroaches to mechanically transmit pathogens.