Volume 87, Issue 3
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645



Ehrlichiosis and anaplasmosis infections among American Indians (AIs) have never been specifically examined, despite high rates of other tick-borne rickettsial diseases among AIs. The epidemiology of ehrlichiosis and anaplasmosis among AIs was analyzed using the National Electronic Telecommunications System for Surveillance (NETSS), Case Report Forms (CRFs), and Indian Health Service (IHS) inpatient and outpatient visits. The 2000–2007 average annual ehrlichiosis and anaplasmosis incidence among AIs reported to NETSS was almost 4-fold lower (4.0/1,000,000) than that using IHS data (14.9). American Indian cases reported from CRFs had a higher proportion of hospitalization (44%) compared with IHS (10%). American Indian incidence of ehrlichiosis and anaplasmosis was higher and showed a different age and geographical distribution than other races. These results highlight the need to improve collaboration between the ehrlichiosis and anaplasmosis surveillance systems for AIs so as to develop interventions that target the unique epidemiology and mitigate the burden of disease among this high-risk population.


Article metrics loading...

Loading full text...

Full text loading...



  1. Chapman AS, Bakken JS, Folk SM, Paddock CD, Bloch KC, Krusell A, Sexton DJ, Buckingham SC, Marshall GS, Storch GA, Dasch GA, McQuiston JH, Swerdlow DL, Dumler SJ, Nicholson WL, Walker DH, Eremeeva ME, Ohl CA, , 2006. Diagnosis and management of tick-borne rickettsial diseases: Rocky Mountain spotted fever, ehrlichioses, and anaplasmosis–United States: a practical guide for physicians and other health-care and public health professionals. MMWR Recomm Rep 55: 127.
  2. Salinas LJ, Greenfield RA, Little SE, Voskuhl GW, , 2010. Tick-borne infections in the southern United States. Am J Med Sci 340: 194201.[Crossref]
  3. Ismail N, Bloch KC, McBride JW, , 2010. Human ehrlichiosis and anaplasmosis. Clin Lab Med 30: 261292.[Crossref]
  4. Graham J, Stockley K, Goldman RD, , 2011. Tick-borne illnesses: a CME update. Pediatr Emerg Care 27: 141147, quiz 148–150.[Crossref]
  5. Dumler JS, Barbet AF, Bekker CP, Dasch GA, Palmer GH, Ray SC, Rikihisa Y, Rurangirwa FR, , 2001. Reorganization of genera in the families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales: unification of some species of Ehrlichia with Anaplasma, Cowdria with Ehrlichia and Ehrlichia with Neorickettsia, descriptions of six new species combinations and designation of Ehrlichia equi and “HGE agent” as subjective synonyms of Ehrlichia phagocytophila . Int J Syst Evol Microbiol 51: 21452165.[Crossref]
  6. Bakken JS, Aguero-Rosenfeld ME, Tilden RL, Wormser GP, Horowitz HW, Raffalli JT, Baluch M, Riddell D, Walls JJ, Dumler JS, , 2001. Serial measurements of hematologic counts during the active phase of human granulocytic ehrlichiosis. Clin Infect Dis 32: 862870.[Crossref]
  7. Dawson JE, Anderson BE, Fishbein DB, Sanchez JL, Goldsmith CS, Wilson KH, Duntley CW, , 1991. Isolation and characterization of an Ehrlichia sp. from a patient diagnosed with human ehrlichiosis. J Clin Microbiol 29: 27412745.
  8. Anderson BE, Dawson JE, Jones DC, Wilson KH, , 1991. Ehrlichia chaffeensis, a new species associated with human ehrlichiosis. J Clin Microbiol 29: 28382842.
  9. Buller RS, Arens M, Hmiel SP, Paddock CD, Sumner JW, Rikhisa Y, Unver A, Gaudreault-Keener M, Manian FA, Liddell AM, Schmulewitz N, Storch GA, , 1999. Ehrlichia ewingii, a newly recognized agent of human ehrlichiosis. N Engl J Med 341: 148155.[Crossref]
  10. Pritt BS, Sloan LM, Johnson DK, Munderloh UG, Paskewitz SM, McElroy KM, McFadden JD, Binnicker MJ, Neitzel DF, Liu G, Nicholson WL, Nelson CM, Franson JJ, Martin SA, Cunningham SA, Steward CR, Bogumill K, Bjorgaard ME, Davis JP, McQuiston JH, Warshauer DM, Wilhelm MP, Patel R, Trivedi VA, Eremeeva ME, , 2011. Emergence of a new pathogenic Ehrlichia species, Wisconsin and Minnesota, 2009. N Engl J Med 365: 422429.[Crossref]
  11. Chen SM, Dumler JS, Bakken JS, Walker DH, , 1994. Identification of a granulocytotropic Ehrlichia species as the etiologic agent of human disease. J Clin Microbiol 32: 589595.
  12. Bakken JS, Dumler JS, Chen SM, Eckman MR, Van Etta LL, Walker DH, , 1994. Human granulocytic ehrlichiosis in the upper Midwest United States. A new species emerging? JAMA 272: 212218.[Crossref]
  13. Dumler JS, Madigan JE, Pusterla N, Bakken JS, , 2007. Ehrlichioses in humans: epidemiology, clinical presentation, diagnosis, and treatment. Clin Infect Dis 45 (Suppl 1): S45S51.[Crossref]
  14. Comer JA, Nicholson WL, Olson JG, Childs JE, , 1999. Serologic testing for human granulocytic ehrlichiosis at a national referral center. J Clin Microbiol 37: 558564.
  15. Public Health Service and Health Care Financing Administration, 2008. International Classification of Diseases, 9th revision, Clinical Modification [CD-ROM]. Sixth ed. Washington, DC: US Department of Health and Human Services.
  16. Paddock CD, Yabsley MJ, , 2007. Ecological havoc, the rise of white-tailed deer, and the emergence of Amblyomma americanum-associated zoonoses in the United States. Curr Top Microbiol Immunol 315: 289324.
  17. Yabsley MJ, Varela AS, Tate CM, Dugan VG, Stallknecht DE, Little SE, Davidson WR, , 2002. Ehrlichia ewingii infection in white-tailed deer (Odocoileus virginianus). Emerg Infect Dis 8: 668671.[Crossref]
  18. 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.
  19. Walls JJ, Greig B, Neitzel DF, Dumler JS, , 1997. Natural infection of small mammal species in Minnesota with the agent of human granulocytic ehrlichiosis. J Clin Microbiol 35: 853855.
  20. Dennis DT, Nekomoto TS, Victor JC, Paul WS, Piesman J, , 1998. Reported distribution of Ixodes scapularis and Ixodes pacificus (Acari: Ixodidae) in the United States. J Med Entomol 35: 629638.[Crossref]
  21. Bakken JS, Krueth J, Wilson-Nordskog C, Tilden RL, Asanovich K, Dumler JS, , 1996. Clinical and laboratory characteristics of human granulocytic ehrlichiosis. JAMA 275: 199205.[Crossref]
  22. Dunn BE, Monson TP, Dumler JS, Morris CC, Westbrook AB, Duncan JL, Dawson JE, Sims KG, Anderson BE, , 1992. Identification of Ehrlichia chaffeensis morulae in cerebrospinal fluid mononuclear cells. J Clin Microbiol 30: 22072210.
  23. Dumler JS, Sutker WL, Walker DH, , 1993. Persistent infection with Ehrlichia chaffeensis . Clin Infect Dis 17: 903905.[Crossref]
  24. Fichtenbaum CJ, Peterson LR, Weil GJ, , 1993. Ehrlichiosis presenting as a life-threatening illness with features of the toxic shock syndrome. Am J Med 95: 351357.[Crossref]
  25. Holman RC, McQuiston JH, Haberling DL, Cheek JE, , 2009. Increasing incidence of Rocky Mountain spotted fever among the American Indian population in the United States. Am J Trop Med Hyg 80: 601605.
  26. McQuiston JH, Holman RC, Groom AV, Kaufman SF, Cheek JE, Childs JE, , 2000. Incidence of Rocky Mountain spotted fever among American Indians in Oklahoma. Public Health Rep 115: 469475.[Crossref]
  27. Folkema AM, Holman RC, McQuiston JH, Cheek JE, , 2012. Trends in clinical diagnoses of Rocky Mountain spotted fever among American Indians, 2001–2008. Am J Trop Med Hyg 86: 152158.[Crossref]
  28. Centers for Disease Control and Prevention, 1991. National Electronic Telecommunications System for Surveillance—United States, 1990–1991. MMWR Morb Mortal Wkly Rep 40: 502503.
  29. Counsel of State and Territorial Epidemiologists, 2000. Position Statements 2000 ID-03: Changes in the Case Definition for Human Ehrlichiosis, and Addition of a New Ehrlichiosis Category as a Condition Placed Under Surveillance According to the National Public Health Surveillance System (NPHSS). Available at: http://www.cste.org/ps/2000/2000-id-03.htm. Accessed June 3, 2011.
  30. Counsel of State and Territorial Epidemiologists, 2007. Position Statements 2007 ID-03: Revision of the National Surveillance Case Definition for Ehrlichiosis (Ehrlichiosis/Anaplasmosis) . Available at: http://www.cste.org/ps/2007ps/2007psfinal/id/07-id-03.pdf. Accessed June 3, 2011.
  31. US Census Bureau, 2008. County Population, Population Change and Estimated Components of Population Change: April 1, 2000 to July 1, 2008. Available at: http://www.census.gov/popest/counties/files/CO-EST2008-ALLDATA.csv. Accessed June 3, 2011.
  32. Horowitz HW, Aguero-Rosenfeld M, Dumler JS, McKenna DF, Hsieh TC, Wu J, Schwartz I, Wormser GP, , 1998. Reinfection with the agent of human granulocytic ehrlichiosis. Ann Intern Med 129: 461463.[Crossref]
  33. Liddell AM, Sumner JW, Paddock CD, Rikihisa Y, Unver A, Buller RS, Storch GA, , 2002. Reinfection with Ehrlichia chaffeensis in a liver transplant recipient. Clin Infect Dis 34: 16441647.[Crossref]
  34. Kleinbaum D, Kupper L, Muller K, Nizam A, , 2008. Applied Regression Analysis and Other Multivariable Methods. Fourth Edition. Belmont, CA: Duxbury Press.
  35. Lehmann E, , 1975. Nonparametrics: Statistical Methods Based on Ranks. San Francisco, CA: Holden-Day Inc.
  36. Centers for Disease Control and Prevention, 2010. Tick-Borne Rickettsial Disease Case Report Form. Available at: http://www.cdc.gov/ticks/forms/2010_tbrd_crf.pdf. Accessed June 23, 2011.
  37. Rosner B, , 2006. Fundamentals of Biostatistics. Sixth edition. Belmont, CA: Thomson Brooks/Cole.
  38. Indian Health Service, 2009. Direct/CHS Inpatient Data: All-diseases, Fiscal Years 2000–2008, National Patient Information Reporting System. Albuquerque, NM: Indian Health Service.
  39. Indian Health Service, 2009. Outpatient Visit Data: All-diseases, Fiscal Years 2000-2008. National Patient Information Reporting System. Rockville, MD: Indian Health Service.
  40. Department of Health and Human Services IHS, 2008. Regional Differences in Indian Health: 2002–2003 Edition. Rockville, MD: IHS.
  41. Kaufman SF, , 1998. Utilization of IHS and Tribal Direct and Contract General Hospitals, FY 1996 and US Non-Federal Short-Stay Hospitals, 1996. Rockville, MD: Indian Health Service.
  42. Department of Health and Human Services IHS, 2009. Trends in Indian Health: 2002–2004 Edition. Rockville, MD: Indian Health Service.
  43. Rhoades DA, D'Angelo AJ, Rhoades ER, Rhoades ER, , 2000. Data sources and subsets of the Indian population. , editor. American Indian Health: Innovations in Health Care, Promotion, and Policy. Baltimore, MD: John Hopkins University Press, 93102.
  44. Dahlgren FS, Mandel EJ, Krebs JW, Massung RF, McQuiston JH, , 2011. Increasing incidence of Ehrlichia chaffeensis and Anaplasma phagocytophilum in the United States, 2000–2007. Am J Trop Med Hyg 85: 124131.[Crossref]
  45. Centers for Disease Control and Prevention, 2008. Anaplasma phagocytophilum transmitted through blood transfusion—Minnesota, 2007. MMWR Morb Mortal Wkly Rep 57: 11451148.
  46. McQuiston JH, Paddock CD, Holman RC, Childs JE, , 1999. The human ehrlichioses in the United States. Emerg Infect Dis 5: 635642.[Crossref]
  47. Openshaw JJ, Swerdlow DL, Krebs JW, Holman RC, Mandel E, Harvey A, Haberling D, Massung RF, McQuiston JH, , 2010. Rocky Mountain spotted fever in the United States, 2000–2007: interpreting contemporary increases in incidence. Am J Trop Med Hyg 83: 174182.[Crossref]
  48. Beugnet F, Kolasinski M, Michelangeli PA, Vienne J, Loukos H, , 2011. Mathematical modeling of the impact of climatic conditions in France on Rhipicephalus sanguineus tick activity and density since 1960. Geospat Health 5: 255263.[Crossref]
  49. Demma LJ, Holman RC, McQuiston JH, Krebs JW, Swerdlow DL, , 2005. Epidemiology of human ehrlichiosis and anaplasmosis in the United States, 2001–2002. Am J Trop Med Hyg 73: 400409.
  50. Bakken JS, Goellner P, Van Etten M, Boyle DZ, Swonger OL, Mattson S, Krueth J, Tilden RL, Asanovich K, Walls J, Dumler JS, , 1998. Seroprevalence of human granulocytic ehrlichiosis among permanent residents of northwestern Wisconsin. Clin Infect Dis 27: 14911496.[Crossref]
  51. Paddock CD, Childs JE, , 2003. Ehrlichia chaffeensis: a prototypical emerging pathogen. Clin Microbiol Rev 16: 3764.[Crossref]
  52. Indian Health Service, 2008. Regional Differences in Indian Health, 2002–2003 Edition. Washington, DC: Government Printing Office.
  53. Jhung MA, Banerjee SN, , 2009. Administrative coding data and health care-associated infections. Clin Infect Dis 49: 949955.[Crossref]
  54. White RH, Brickner LA, Scannell KA, , 2004. ICD-9-CM codes poorly indentified venous thromboembolism during pregnancy. J Clin Epidemiol 57: 985988.[Crossref]
  55. Baldwin LM, Hollow WB, Casey S, Hart LG, Larson EH, Moore K, Lewis E, Andrilla CH, Grossman DC, , 2008. Access to specialty health care for rural American Indians in two states. J Rural Health 24: 269278.[Crossref]
  56. Cunningham PJ, Cornelius LJ, , 1995. Access to ambulatory care for American Indians and Alaska Natives; the relative importance of personal and community resources. Soc Sci Med 40: 393407.[Crossref]
  57. Smith N, Iyer RL, Langer-Gould A, Getahun DT, Strickland D, Jacobsen SJ, Chen W, Derose SF, Koebnick C, , 2010. Health plan administrative records versus birth certificate records: quality of race and ethnicity information in children. BMC Health Serv Res 10: 316.[Crossref]
  58. Thoroughman DA, Frederickson D, Cameron HD, Shelby LK, Cheek JE, , 2002. Racial misclassification of American Indians in Oklahoma State surveillance data for sexually transmitted diseases. Am J Epidemiol 155: 11371141.[Crossref]
  59. Hahn RA, Mulinare J, Teutsch SM, , 1992. Inconsistencies in coding of race and ethnicity between birth and death in US infants. A new look at infant mortality, 1983 through 1985. JAMA 267: 259263.[Crossref]
  60. Epstein M, Moreno R, Bacchetti P, , 1997. The underreporting of deaths of American Indian children in California, 1979 through 1993. Am J Public Health 87: 13631366.[Crossref]
  61. Dahlgren FS, Moonesinghe R, McQuiston JH, , 2011. Race and rickettsiae: a United States perspective. Am J Trop Med Hyg 85: 11241125.[Crossref]
  62. Carpenter CF, Gandhi TK, Kong LK, Corey GR, Chen SM, Walker DH, Dumler JS, Breitschwerdt E, Hegarty B, Sexton DJ, , 1999. The incidence of ehrlichial and rickettsial infection in patients with unexplained fever and recent history of tick bite in central North Carolina. J Infect Dis 180: 900903.[Crossref]
  63. Olano JP, Masters E, Hogrefe W, Walker DH, , 2003. Human monocytotropic ehrlichiosis, Missouri. Emerg Infect Dis 9: 15791586.[Crossref]

Data & Media loading...

  • Received : 25 Jan 2012
  • Accepted : 12 Apr 2012

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error