Volume 83, Issue 3
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Rocky Mountain spotted fever (RMSF) is the most common tick-borne illness in Tennessee. Little is known about the occurrence of the causative agent, in ticks in Tennessee. To better understand the prevalence and distribution of rickettsial agents in ticks, we tested 1,265 , , and adult and nymphal ticks. Additionally, we tested 231 larvae. Ticks were collected from 49 counties from humans, wild animals, domestic canines, and flannel drags. Spotted fever group rickettsiae (SFGR) DNA was detected by polymerase chain reaction (PCR) in 32% of adult and nymphal ticks. A total minimum infection rate of 85.63 was found in larval pools tested. Three rickettsial species, , and were identified by molecular analysis. was not detected. This study suggests that some RMSF cases reported in Tennessee may be caused by cross-reactivity with other SFGR antigenically related to


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  1. Burgdorfer W, , 1975. A review of Rocky Mountain spotted fever (tick-borne typhus), its agent, and its tick vectors in the United States. J Med Entomol 12: 269278.[Crossref] [Google Scholar]
  2. Durden LA, Kollars TM, Jr, 1992. An annotated list of the ticks (Acari: Ixodoidea) of Tennessee, with records of four exotic species for the United States. Bulletin of the Society for Vector Ecologists 17: 125131. [Google Scholar]
  3. Wikswo ME, Hu R, Metzger ME, Eremeeva ME, , 2007. Detection of Rickettsia rickettsii and Bartonella henselae in Rhipicephalus sanguineus ticks from California. J Med Entomol 44: 158162.[Crossref] [Google Scholar]
  4. Demma LJ, Traeger MS, Nicholson WL, Paddock CD, Blau DM, Eremeeva ME, Dasch GA, Levin ML, Singleton J, Jr Zaki SR, Cheek JE, Swerdlow DL, McQuiston JH, , 2005. Rocky Mountain spotted fever from an unexpected tick vector in Arizona. N Engl J Med 353: 587594.[Crossref] [Google Scholar]
  5. Dalton MJ, Clarke MJ, Holman RC, Krebs JW, Fishbein DB, Olson JG, Childs JE, , 1995. National surveillance for Rocky Mountain spotted fever, 1981–1992: epidemiologic summary and evaluation of risk factors for fatal outcome. Am J Trop Med Hyg 52: 405413. [Google Scholar]
  6. Treadwell TA, Holman RC, Clarke MJ, Krebs JW, Paddock CD, Childs JE, , 2000. Rocky Mountain spotted fever in the United States, 1993–1996. Am J Trop Med Hyg 63: 2126. [Google Scholar]
  7. Adjemian JZ, Krebs J, Mandel E, McQuiston J, , 2009. Spatial clustering by disease severity among reported Rocky Mountain spotted fever cases in the United States, 2001–2005. Am J Trop Med Hyg 80: 7277. [Google Scholar]
  8. Wikswo ME, Hu R, Dasch GA, Krueger L, Arugay A, Jones K, Hess B, Bennett S, Kramer V, Eremeeva ME, , 2008. Detection and identification of spotted fever group rickettsiae in Dermacentor species from southern California. J Med Entomol 45: 509516.[Crossref] [Google Scholar]
  9. Parola P, Paddock CD, Raoult D, , 2005. Tick-borne rickettsioses around the world: emerging diseases challenging old concepts. Clin Microbiol Rev 18: 719756.[Crossref] [Google Scholar]
  10. Stromdahl EY, Vince MA, Billingsley PM, Dobbs NA, Williamson PC, , 2008. Rickettsia amblyommii infecting Amblyomma americanum larvae. Vector Borne Zoonotic Dis 8: 1524.[Crossref] [Google Scholar]
  11. Apperson CS, Engber B, Nicholson WL, Mead DG, Engel J, Yabsley MJ, Dail K, Johnson J, Watson DW, , 2008. Tick-borne diseases in North Carolina: is “Rickettsia amblyommii” a possible cause of rickettsiosis reported as Rocky Mountain spotted fever? Vector Borne Zoonotic Dis 8: 597606.[Crossref] [Google Scholar]
  12. Burgdorfer W, Cooney JC, Thomas LA, , 1974. Zoonotic potential (Rocky Mountain spotted fever and tularemia) in the Tennessee Valley region. II. Prevalence of Rickettsia rickettsi and Francisella tularensis in mammals and ticks from Land Between the Lakes. Am J Trop Med Hyg 23: 109117. [Google Scholar]
  13. Kollars TM, Jr Kengluecha A, , 2001. Spotted fever group Rickettsia in Dermacentor variabilis (Acari: Ixodidae) infesting raccoons (Carnivora: Procyonidae) and opossums (Marsupialia: Didelphimorphidae) in Tennessee. J Med Entomol 38: 601602.[Crossref] [Google Scholar]
  14. Cohen SB, Freye JD, Dunlap BG, Dunn JR, Jones TF, Moncayo AC, , 2010. Host associations of Dermacentor, Amblyommai, and Ixodes (Acari: Ixodidae) ticks in Tennessee. J Med Entomol, in press. [Google Scholar]
  15. Keirans JE, Litwak TR, , 1989. Pictorial key to the adults of hard ticks, family Ixodidae (Ixodida:Ixodoidea), east of the Mississippi River. J Med Entomol 26: 435448.[Crossref] [Google Scholar]
  16. Loftis AD, Reeves WK, Szumlas DE, Abbassy MM, Helmy IM, Moriarity JR, Dasch GA, , 2006. Surveillance of Egyptian fleas for agents of public health significance: Anaplasma, Bartonella, Coxiella, Ehrlichia, Rickettsia, and Yersinia pestis . Am J Trop Med Hyg 75: 4148. [Google Scholar]
  17. Eremeeva M, Yu X, Raoult D, , 1994. Differentiation among spotted fever group rickettsiae species by analysis of restriction fragment length polymorphism of PCR-amplified DNA. J Clin Microbiol 32: 803810. [Google Scholar]
  18. Griffith GE, Omernik JM, Azevedo SH, , 1997. Ecoregions of Tennessee. EPA/600/R-97/022. Corvallis, OR: U.S. Environmental Protection Agency, National Health and Environmental Effects Research Laboratory. [Google Scholar]
  19. Gordon JC, Gordon SW, Peterson E, Philip RN, , 1984. Epidemiology of Rocky Mountain spotted fever in Ohio, 1981: serologic evaluation of canines and rickettsial isolation from ticks associated with human case exposure sites. Am J Trop Med Hyg 33: 10261031. [Google Scholar]
  20. Anderson JF, Magnarelli LA, Philip RN, Burgdorfer W, , 1986. Rickettsia rickettsii and Rickettsia montana from Ixodid ticks in Connecticut. Am J Trop Med Hyg 35: 187191. [Google Scholar]
  21. Breitschwerdt EB, Walker DH, Levy MG, Burgdorfer W, Corbett WT, Hurlbert SA, Stebbins ME, Curtis BC, Allen DA, , 1988. Clinical, hematologic, and humoral immune response in female dogs inoculated with Rickettsia rickettsii and Rickettsia montana . Am J Vet Res 49: 7076. [Google Scholar]
  22. Stromdahl EY, Evans SR, O'Brien JJ, Gutierrez AG, , 2001. Prevalence of infection in ticks submitted to the human tick test kit program of the U.S. Army Center for Health Promotion and Preventive Medicine. J Med Entomol 38: 6774.[Crossref] [Google Scholar]
  23. Macaluso KR, Sonenshine DE, Ceraul SM, Azad AF, , 2002. Rickettsial infection in Dermacentor variabilis (Acari: Ixodidae) inhibits transovarial transmission of a second Rickettsia . J Med Entomol 39: 809813.[Crossref] [Google Scholar]
  24. Carmichael JR, Fuerst PA, , 2006. A rickettsial mixed infection in a Dermacentor variabilis tick from Ohio. Ann NY Acad Sci 1078: 334337.[Crossref] [Google Scholar]
  25. Billings AN, Teltow GJ, Weaver SC, Walker DH, , 1998. Molecular characterization of a novel Rickettsia species from Ixodes scapularis in Texas. Emerg Infect Dis 4: 305309.[Crossref] [Google Scholar]
  26. Noda H, Munderloh UG, Kurtti TJ, , 1997. Endosymbionts of ticks and their relationship to Wolbachia spp. and tick-borne pathogens of humans and animals. Appl Environ Microbiol 63: 39263932. [Google Scholar]
  27. Mixson TR, Campbell SR, Gill JS, Ginsberg HS, Reichard MV, Schulze TL, Dasch GA, , 2006. Prevalence of Ehrlichia, Borrelia, and Rickettsial agents in Amblyomma americanum (Acari: Ixodidae) collected from nine states. J Med Entomol 43: 12611268. [Google Scholar]
  28. Childs JE, Paddock CD, , 2003. The ascendancy of Amblyomma americanum as a vector of pathogens affecting humans in the United States. Annu Rev Entomol 48: 307337.[Crossref] [Google Scholar]
  29. Dasch GA, Kelly DJ, Richards AL, Sanchez JL, Rives CC, , 1993. Western blotting analysis of sera from military personnel exhibiting serological reactivity to spotted fever group Rickettsiae. Am Soc Trop Med Hyg 49 (Suppl. 3): 220. [Google Scholar]
  30. Billeter SA, Blanton HL, Little SE, Levy MG, Breitschwerdt EB, , 2007. Detection of Rickettsia amblyommii in association with a tick bite rash. Vector Borne Zoonotic Dis 7: 607610.[Crossref] [Google Scholar]
  31. Paddock CD, Sumner JW, Comer JA, Zaki SR, Goldsmith CS, Goddard J, McLellan SL, Tamminga CL, Ohl CA, , 2004. Rickettsia parkeri: a newly recognized cause of spotted fever rickettsiosis in the United States. Clin Infect Dis 38: 805811.[Crossref] [Google Scholar]
  32. Raoult D, Paddock CD, , 2005. Rickettsia parkeri infection and other spotted fevers in the United States. N Engl J Med 353: 626627.[Crossref] [Google Scholar]
  33. Whitman TJ, Richards AL, Paddock CD, Tamminga CL, Sniezek PJ, Jiang J, Byers DK, Sanders JW, , 2007. Rickettsia parkeri infection after tick bite, Virginia. Emerg Infect Dis 13: 334336.[Crossref] [Google Scholar]
  34. Cohen SB, Yabsley MJ, Garrison LE, Freye JD, Dunlap BG, Dunn JR, Mead DG, Jones TF, Moncayo AC, , 2009. Rickettsia parkeri in Amblyomma americanum ticks, Tennessee and Georgia, USA. Emerg Infect Dis 15: 14711473.[Crossref] [Google Scholar]
  35. Merten HA, Durden LA, , 2000. A state-by-state survey of ticks recorded from humans in the United States. J Vector Ecol 25: 102113. [Google Scholar]

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  • Received : 17 Apr 2009
  • Accepted : 03 Mar 2010
  • Published online : 07 Sep 2010

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