Assistant Professor University of South Dakota Vermillion, South Dakota
The German cockroach (Blattella germanica) frequently harbors and has been linked to human outbreaks of enteric bacterial pathogens, but the mechanisms of vector-borne transmission are not fully clear. Transmission of pathogens by cockroaches has been previously described as mechanical. Mechanical transmission is a wholly passive process that involves physical transfer of a pathogen from one location or host to another but lacks bacterial replication in the vector and active bacterial processes that promote vector colonization or transmission. Towards the goal of obtaining novel, detailed insight into the mechanisms of pathogen transmission by cockroaches, our laboratory is actively conducting controlled infections of cockroaches with several relevant enteric bacteria. Our data indicate that transmission of some enteric bacteria by cockroaches is not solely mechanical but may resemble biological transmission by other insect vectors that intake human pathogenic bacteria from infected hosts and are subsequently colonized, enabling active dissemination. Findings demonstrating that cockroach-pathogen interactions are highly dynamic and influenced by a combination of microbial, host, and environmental parameters will be discussed. These findings suggest that cockroaches and their control may be more important for infection prevention than is currently appreciated.
