title: Seroepidemiologic study of human infections with spotted fever group Rickettsiae in North Carolina.
abstract: Increasing entomologic and epidemiologic evidence suggests that spotted fever group rickettsiae (SFGR) other than Rickettsia rickettsii are responsible for spotted fever rickettsioses in the United States. A retrospective seroepidemiologic study was conducted on stored acute- and convalescent-phase sera that had been submitted for Rocky Mountain spotted fever testing to the North Carolina State Laboratory of Public Health. We evaluated the serologic reactivity of the paired sera to R. rickettsii, Rickettsia parkeri, and Rickettsia amblyommii antigens. Of the 106 eligible pairs tested, 21 patients seroconverted to one or more antigens. Cross-reactivity to multiple antigens was observed in 10 patients, and seroconversions to single antigens occurred in 11 patients, including 1 against R. rickettsii, 4 against R. parkeri, and 6 against R. amblyommii. Cross-absorption of cross-reactive sera and/or Western blots identified two presumptive cases of infection with R. parkeri, two presumptive cases of infection with R. rickettsii, and one presumptive case of infection with R. amblyommii. These findings suggest that species of SFGR other than R. rickettsii are associated with illness among North Carolina residents and that serologic testing using R. rickettsii antigen may miss cases of spotted fever rickettsioses caused by other species of SFGR.
authors.affiliation: Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA meagan_vaughn@rhoworld.com.
authors.forename: Meagan F
authors.initials: MF
authors.lastname: Vaughn
authors.affiliation: Tennessee Department of Health, Nashville, Tennessee, USA.
authors.forename: Josie
authors.initials: J
authors.lastname: Delisle
authors.affiliation: North Carolina State Laboratory of Public Health, Raleigh, North Carolina, USA.
authors.forename: Joey
authors.initials: J
authors.lastname: Johnson
authors.affiliation: North Carolina State Laboratory of Public Health, Raleigh, North Carolina, USA.
authors.forename: Gaylen
authors.initials: G
authors.lastname: Daves
authors.affiliation: North Carolina Division of Public Health, Raleigh, North Carolina, USA.
authors.forename: Carl
authors.initials: C
authors.lastname: Williams
authors.affiliation: North Carolina Division of Public Health, Raleigh, North Carolina, USA.
authors.forename: Jodi
authors.initials: J
authors.lastname: Reber
authors.affiliation: Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, Center for Tropical Diseases, University of Texas Medical Branch at Galveston, Galveston, Texas, USA.
authors.forename: Nicole L
authors.initials: NL
authors.lastname: Mendell
authors.affiliation: Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, Center for Tropical Diseases, University of Texas Medical Branch at Galveston, Galveston, Texas, USA.
authors.forename: Donald H
authors.initials: DH
authors.lastname: Bouyer
authors.affiliation: Rickettsial Zoonoses Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
authors.forename: William L
authors.initials: WL
authors.lastname: Nicholson
authors.affiliation: Tennessee Department of Health, Nashville, Tennessee, USA.
authors.forename: Abelardo C
authors.initials: AC
authors.lastname: Moncayo
authors.affiliation: Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
authors.forename: Steven R
authors.initials: SR
authors.lastname: Meshnick
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood*; D015153:Blotting, Western; D002648:Child; D002675:Child, Preschool; D003429:Cross Reactions; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009657:North Carolina / Q000453:epidemiology; D012189:Retrospective Studies; D012281:Rickettsia / Q000276:immunology*; D012282:Rickettsia Infections / Q000453:epidemiology*; D016036:Seroepidemiologic Studies; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial