Program Description
Ticks have two body types, hard (Ixodes scapularis, the common deer tick, on the left) and soft (Orthinodoros hermsi on the right).
The Medical Entomology Section investigates bacterial pathogens transmitted by blood-feeding arthropods. Emphasis is directed toward the Lyme disease spirochete, Borrelia burgdorferi, and a relapsing fever spirochete, Borrelia hermsii, in their respective tick vectors. Other pathogenic spirochetes are also studied. Live colonies of ticks allow for studies to elucidate factors important for the infection of these bacteria in arthropods and for their biological transmission when ticks feed. Understanding bacterial adaptations associated with transmission is linked to developing better prevention and diagnostic strategies.
Watch as a research team led by Tom Schwan, Ph.D., travels to a remote Malian village in search of tickborne relapsing fever.
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Biography
Dr. Schwan received his Ph.D. in 1983 in parasitology from the University of California at Berkeley, studying the ecology of fleas and plague in Lake Nakuru National Park, Kenya. From 1983 to 1986, he was a postdoctoral fellow at the Yale Arbovirus Research Unit, Yale University School of Medicine, studying tickborne viruses. He joined the Rocky Mountain Laboratories in 1986. He served on the editorial board of the Journal of Clinical Microbiology for nine years and is on the editorial boards of Vector Borne and Zoonotic Diseases and Emerging Infectious Diseases.
Research Group
Tom Schwan, Colleen Miller, Tammi Johnson, Brandi Williamson, Robert Fischer, Sandy Stewart, Paul Policastro, Marie Feldmann, Ousmane Maiga
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Selected Publications
Lopez JE, Mccoy BN, Krajacich BJ, Schwan TG. Acquisition and subsequent transmission of Borrelia hermsii by the soft tick Ornithodoros hermsi. J Med Entomol. 2011 Jul;48(4):891-5.
McCoy BN, Raffel SJ, Lopez JE, Schwan TG. Bloodmeal size and spirochete acquisition of Ornithodoros hermsi (Acari: Argasidae) during feeding. J Med Entomol. 2010 Nov;47(6):1164-72.
Safronetz D, Lopez JE, Sogoba N, Traore’ SF, Raffel SJ, Fischer ER, Ebihara H, Branco L, Garry RF, Schwan TG, Feldmann H. Detection of Lassa virus, Mali. Emerg Infect Dis. 2010 Jul;16(7):1123-6.
Lopez JE, Schrumpf ME, Nagarajan V, Raffel SJ, McCoy BN, Schwan TG. A novel surface antigen of relapsing fever spirochetes can discriminate between relapsing fever and Lyme borreliosis. Clin Vaccine Immunol. 2010 Apr;17(4):564-71.
Piesman J, Schwan TG. Ecology of borreliae and their arthropod vectors. In: Samuels DS, Radolf JD, editors. Borrelia: Molecular Biology, Host Interaction and Pathogenesis. Norfolk, UK: Caister Academic Press; 2010. p. 251-78.
Schwan TG, Raffel SJ, Schrumpf ME, Gill JS, Piesman J. Characterization of a novel relapsing fever spirochete in the midgut, coxal fluid, and salivary glands of the bat tick Carios kelleyi. Vector Borne Zoonotic Dis. 2009 Dec;9(6):643-7.
For a complete listing, visit PubMed.
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Patents
Simpson WJ, Schwan TG, Claude G, inventors; Government of the United States of America as represented by the Secretary of the Department of Health, assignee. Specific and sensitive diagnostic test for Lyme disease. United States patent US 5,489,511. 1996 Feb 6.
Simpson WJ, Schwan TG, inventors. The United States of America, represented by the Secretary, United States Department of Commerce, assignee. Antigenic proteins of Borrelia burgdorferi. World patent WO/1991/013630. 1991 Sep 19. English.
Dorward DW, Schwan TG, Garon CF, inventors. The United States of America, represented by the Secretary, United States Department of Commerce, assignee. Method of detection of Borrelia burgdorferi, purified antigen thereof, and antibody capable of binding therewith. World patent WO/1991/13096. 1991 Sep 5. English.