The genus Anaplasma includes a diverse group of tick-borne pathogens found exclusively within membrane-bound vacuoles in host cells. While A. marginale, A. centrale and A. ovis, vectored by Dermacentor and Rhipicephalus ticks, are host-specific for ruminants, A. phagocytophilum, vectored by Ixodes spp., infects a wide range of hosts. In ticks Anaplasma undergoes a developmental cycle that is co...

The transition between infection of the mammalian host and colonization of an arthropod vector is required for the ongoing transmission of a broad array of pathogens, from viruses to protozoa. Understanding how this transition is mediated provides opportunities to disrupt transmission through either chemotherapy or immunization. We used an unbiased proteomic screen to identify Anaplasma margina...

by Eric L. Sutten, M.S. Washington State University August 2009 Chair: Wendy C. Brown Anaplasma marginale is an economically important tick-borne intraerythrocytic rickettsial pathogen of cattle that can cause fever, weight loss and death upon acute infection in naïve hosts. Immunization with isolated outer membrane (OM) fractions elicits protective immunity against infection, whereas immunizat...

The seroprevalence of Anaplasma marginale, Babesia bigemina, Babesia bovis and Trypanosoma vivax and the risk factors for these infections were investigated in 509 cows on 37 farms in the semiarid region of Paraíba, northeastern Brazil. Cow serum samples were tested by means of immunofluorescence assay (IFA) against each specific antigen. The mean seroprevalence values per farm were 15.0% (rang...

Anaplasma marginale is a Gram-negative, obligate intraerythrocytic bacterium that causes bovine anaplasmosis. While hard ticks of the genera Dermacentor and Rhipicephalus can be biological vectors, transmitting this pathogen via saliva during blood meals, blood-sucking insects, fomites play role as mechanical vectors. Little known about interaction between Argasidae ticks. Among soft ticks, Orn...

During the period from June 1974 to June 1975, five bovine fetuses between seven to nine months old were received for necropsy from four different counties of the S. Paulo State, Brazil. All of them were from brucellosis-free herds. Necropsy revealed slight liver enlargement generally accompanied by capsular petechial hemorrhages. Enlargement and congestion of the spleen, epicardial and endocar...

Bacterial pathogens in the genus Anaplasma generate surface coat variants by gene conversion of chromosomal pseudogenes into single-expression sites. These pseudogenes encode unique surface-exposed hypervariable regions flanked by conserved domains, which are identical to the expression site flanking domains. In addition, Anaplasma marginale generates variants by recombination of oligonucleotid...

To determine exposure to a variety of infectious diseases potentially important for native ungulates, livestock, and humans, serum samples from 114 (94 adults, 20 fawns) female white-tailed deer (Odocoileus virginianus) were collected during January 2000-03 from multiple locations in southeast (SE) and southwest (SW) Minnesota. Antibody prevalence was determined for the following pathogens: Myc...