Achievement

Tammi Johnson researches the ecology of tick-borne relapsing fever (TBRF) in western North America. TBRF is caused by the bacterium Borrelia hermsii and vectored by the long-lived, soft-bodied tick Ornithodoros hermsi. To date, there has been very limited understanding of the underlying ecology of this disease system. Tammi employs a multifaceted approach to elucidate the role of hosts and vectors in this system. Pathogen prevalence, incidence, and genetic diversity are combined with population genetics, habitat modeling, and disease modeling in order to investigate the dynamics and distribution of B. hermsii in the Flathead Valley, Lake County, Montana. To date, they have trapped 355 small mammals and have performed serology to detect B. hermsii specific antibodies. All species trapped have been found seropositive, and 38% of individuals were seropositive. Whole chromosome single nucleotide polymorphism (SNP) analysis was performed for 32 B. hermsii isolates.