Ahead of Print -Tickborne Relapsing Fever, Bitterroot Valley, Montana, USA - Volume 21, Number 2—February 2015 - Emerging Infectious Disease journal - CDC

full-text ►

Ahead of Print -Tickborne Relapsing Fever, Bitterroot Valley, Montana, USA - Volume 21, Number 2—February 2015 - Emerging Infectious Disease journal - CDC

Volume 21, Number 2—February 2015

Research

Tickborne Relapsing Fever, Bitterroot Valley, Montana, USA

On This Page

• Case-Patient
• Materials and Methods
• Results
• Discussion
• Suggested Citation

Figures

• Figure 1
• Figure 2
• Figure 3

Tables

• Table 1
• Table 2

Downloads

• RIS[TXT - 2 KB]

Joshua Christensen, Robert J. Fischer, Brandi N. McCoy, Sandra J. Raffel, and Tom G. Schwan 

Author affiliations: St. Patrick Hospital, Missoula, Montana, USA (J. Christensen); University of Montana College of Health Professionals and Biomedical Sciences, Missoula (J. Christensen); National Institute of Allergy and Infectious Diseases, Hamilton, Montana, USA (R.J. Fischer, B.N. McCoy, S.J. Raffel, T.G. Schwan)

Suggested citation for this article

Abstract

In July 2013, a resident of the Bitterroot Valley in western Montana, USA, contracted tickborne relapsing fever caused by an infection with the spirochete Borrelia hermsii. The patient’s travel history and activities before onset of illness indicated a possible exposure on his residential property on the eastern side of the valley. An onsite investigation of the potential exposure site found the vector, Ornithodoros hermsi ticks, and 1 chipmunk infected with spirochetes, which on the basis of multilocus sequence typing were identical to the spirochete isolated from the patient. Field studies in other locations found additional serologic evidence and an infected tick that demonstrated a wider distribution of spirochetes circulating among the small mammal populations. Our study demonstrates that this area of Montana represents a previously unrecognized focus of relapsing fever and poses a risk for persons of acquiring this tickborne disease.

Seminal research on tickborne diseases of humans in North America began more than a century ago with the discovery in 1906 that an illness locally called black measles, which affected persons in the Bitterroot Valley of western Montana, USA, resulted from the bite of a bacteria-infected Rocky Mountain wood tick (1,2). What soon followed was the establishment of a multidisciplinary public health program to control this newly identified disease, now called Rocky Mountain spotted fever, which was caused by Rickettsia rickettsii, and a search was conducted for other diseases in nature that resulted from the bite of pathogen-infected ticks. These programs were based at a newly funded state laboratory in Hamilton in the Bitterroot Valley, a facility that was soon incorporated into the US Public Health Service and is now the Rocky Mountain Laboratories (RML) of the National Institute of Allergy and Infectious Diseases.

One of the many diseases studied at the RML since the early 1930s has been tickborne relapsing fever (RML, unpub. data) (3,4). In North America, this zoonosis is associated with 3 species of spirochetes, but most human cases are caused by Borrelia hermsii, which is found in scattered foci in the western United States and southern British Columbia, Canada (5,6). The specific vector of this spirochete is the Ornithodoros hermsi tick (7), which is found in higher-elevation coniferous forests where its preferred rodent hosts, primarily squirrels and chipmunks, are also found (6). In spite of the many decades of intensive research on ticks and tickborne diseases in the Bitterroot Valley, the tick O. hermsi, the spirochete B. hermsii, or an autochthonous human case of relapsing fever has not been observed in this region of Montana, until now. We report a case of tickborne relapsing fever in a person in this region.

Figure 1. A) Spirochetes in blood smear of a 55-year-old man with tickborne relapsing fever, Bitterroot Valley, Montana, USA (Giemsa stain). Erythrocyte diameters are ≈6–8 µm. B) Spirochetes in blood smear of the...

Dr. Christensen is an infectious disease specialist at St. Patrick’s Hospital and the University of Montana, Missoula, Montana. His research interests include zoonotic and mycobacterial infections.

Acknowledgments

We thank Charles Nead for detecting the spirochetes in the blood smear; Karra Markley for providing the image of the Giemsa-stained blood smear; George Risi, David Safronetz, and Joe Hinnebusch for reviewing the manuscript; and Gary Hettrick for assistance with the figures.

This study was supported in part by the Intramural Research Program, National Institute of Allergy and Infectious Diseases, National Institutes of Health.

References

1. Ricketts HT. The transmission of Rocky Mountain spotted fever by the bite of the wood tick (Dermacentor occidentalis). JAMA. 1906;47:358. DOI
2. King WW. Experimental transmission of Rocky Mountain spotted fever by means of the ticks. Preliminary note. Public Health Rep. 1906;21:863–4file:///\\\\\\\\cdc\\\\project\\\\CCID_NCPDCID_DEISS_EIDJ\\\\EID%20Production\\\\Editorial\\\\Vol21No02\\\\%20. DOIPubMed
3. Davis GE. Ornithodoros turicata: the possible vector of relapsing fever in southwestern Kansas. Public Health Rep. 1936;51:1719. DOI
4. Davis GE. Relapsing fever: Ornithodoros hermsi a vector in Colorado. Public Health Rep. 1939;54:2178–80. DOI
5. Dworkin MS, Schwan TG, Anderson DE. Tick-borne relapsing fever in North America. Med Clin North Am. 2002;86:417–33. DOIPubMed
6. 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.
7. Davis GE. Species unity or plurality of the relapsing fever spirochetes. In: Moulton FR, editor. A symposium of relapsing fever in the Americas. Washington (DC): American Association for the Advancement of Science; 1942. p. 41–7.
8. Barbour AG, Hayes SF, Heiland RA, Schrumpf ME, Tessier SLA. Borrelia-specific monoclonal antibody binds to a flagellar epitope. Infect Immun.1986;52:549–54 .PubMed
9. Schwan TG, Gage KL, Karstens RH, Schrumpf ME, Hayes SF, Barbour AG. Identification of the tick-borne relapsing fever spirochete Borrelia hermsiiby using a species-specific monoclonal antibody. J Clin Microbiol. 1992;30:790–5 .PubMed
10. Schwan TG, Policastro PF, Miller Z, Thompson RL, Damrow T, Keirans JE. Tick-borne relapsing fever caused by Borrelia hermsii, Montana. Emerg Infect Dis. 2003;9:1151–4. DOIPubMed
11. Barbour AG. Isolation and cultivation of Lyme disease spirochetes. Yale J Biol Med. 1984;57:521–5 .PubMed
12. Battisti JM, Raffel SJ, Schwan TG. A system for site-specific genetic manipulation of the relapsing fever spirochete Borrelia hermsii. In: DeLeo FR, Otto M, editors. Methods in molecular biology 431: bacterial pathogenesis methods and protocols. Totowa (NJ): Humana Press; 2008. p. 69–84.
13. Porcella SF, Raffel SJ, Anderson DE Jr, Gilk SD, Bono JL, Schrumpf ME, Variable tick protein in two genomic groups of the relapsing fever spirocheteBorrelia hermsii in western North America. Infect Immun. 2005;73:6647–58. DOIPubMed
14. Bunikis J, Garpmo U, Tsao J, Berglund J, Fish D, Barbour AG. Sequence typing reveals extensive strain diversity of the Lyme borreliosis agentsBorrelia burgdorferi in North America and Borrelia afzelii in Europe. Microbiology. 2004;150:1741–55. DOIPubMed
15. Lopez JE, Schrumpf ME, Raffel SJ, Policastro PF, Porcella SF, Schwan TG. Relapsing fever spirochetes retain infectivity after prolonged in vitrocultivation. Vector Borne Zoonotic Dis. 2008;8:813–20. DOIPubMed
16. Southern PM, Sanford JP. Relapsing fever: a clinical and microbiological review. Medicine (Baltimore). 1969;48:129–49. DOI
17. Foresman KR. The wild mammals of Montana. Lawrence (KS): The American Society of Mammalogists; 2001.
18. Schwan TG, Anderson JM, Lopez JE, Fischer RJ, Raffel SJ, McCoy BN, Endemic foci of the tick-borne relapsing fever spirochete Borrelia crocidurae in Mali, West Africa, and the potential for human infection. PLoS Negl Trop Dis. 2012;6:e1924. .DOI
19. Schwan TG, Schrumpf ME, Hinnebusch BJ, Anderson DE, Konkel ME. GlpQ: an antigen for serological discrimination between relapsing fever and Lyme borreliosis. J Clin Microbiol. 1996;34:2483–92 .PubMed
20. Schwan TG, Raffel SJ, Schrumpf ME, Webster LS, Marques AR, Spano R, Tick-borne relapsing fever and Borrelia hermsii, Los Angeles County, California, USA. Emerg Infect Dis. 2009;15:1026–31. DOIPubMed
21. Schwan TG, Raffel SJ, Schrumpf ME, Porcella SF. Diversity and distribution of Borrelia hermsii. Emerg Infect Dis. 2007;13:436–42. DOIPubMed
22. Dworkin MS, Anderson DE Jr, Schwan TG, Shoemaker PC, Banerjee SN, Kassen BO, Tick-borne relapsing fever in the northwestern United States and southwestern Canada. Clin Infect Dis. 1998;26:122–31. DOIPubMed
23. Kauffmann DJH, Wormser GP. Ocular Lyme disease: a case report and review of the literature. Br J Ophthalmol. 1990;74:325–7. DOIPubMed
24. Amaratunge BC, Camuglia JE, Hall AJ. Syphilitic uveitis: a review of clinical manifestations and treatment outcomes of syphilitic uveitis in human immunodeficiency virus-positive and negative patients. Clin Experiment Ophthalmol. 2010;38:68–74. DOIPubMed
25. Verma A, Stevenson B. Leptospiral uveitis - there is more to it than meets the eye! Zoonoses Public Health. 2012;59(Suppl 2):132–41.DOIPubMed
26. Hamilton JB. Ocular complications in relapsing fever. Br J Ophthalmol. 1943;27:68–80. DOIPubMed
27. Gillespie JO. Relapsing fever in the United States. JAMA. 1935;104:1878–81. DOI
28. Horton JM, Blaser MJ. The spectrum of relapsing fever in the Rocky Mountains. Arch Intern Med. 1985;145:871–5. DOIPubMed
29. Lim LL, Rosenbaum JT. Borrelia hermsii causing relapsing fever and uveitis. Am J Ophthalmol. 2006;142:348–9. DOIPubMed
30. Uhlmann EJ, Seed PC, Schwan TG, Storch GA. Polymerase chain reaction of tick-borne relapsing fever caused by Borrelia hermsii. Pediatr Infect Dis J. 2007;26:267–9. DOIPubMed
31. Policastro PF, Raffel SJ, Schwan TG. Borrelia hermsii acquisition order in superinfected ticks determines transmmission efficiency. Infect Immun.2013;81:2899–908. DOIPubMed
32. Porter GS, Beck MD, Stevens IM. Relapsing fever in California. Am J Public Health Nations Health. 1932;22:1136–40. DOIPubMed
33. Trevejo RT, Schriefer ME, Gage KL, Safranek TJ, Orloski KA, Pape WJ, An interstate outbreak of tick-borne relapsing fever among vacationers at a Rocky Mountain cabin. Am J Trop Med Hyg. 1998;58:743–7 .PubMed
34. Fritz CL, Bronson LR, Smith CR, Schriefer ME, Tucker JR, Schwan TG. Isolation and characterization of Borrelia hermsii associated with two foci of tick-borne relapsing fever in California. J Clin Microbiol. 2004;42:1123–8. DOIPubMed
35. Fritz CL, Payne JR, Schwan TG. Serological evidence for Borrelia hermsii infection in rodents on federally owned recreational areas in California.Vector Borne Zoonotic Dis. 2013;13:376–81. DOIPubMed
36. Gholkar N, Lehman D. Images in clinical medicine: Borrelia hermsii (relapsing fever). N Engl J Med. 2013;368:266 . DOIPubMed

Figures

• Figure 1. A) Spirochetes in blood smear of a 55-year-old man with tickborne relapsing fever, Bitterroot Valley, Montana, USA (Giemsa stain). Erythrocyte diameters are ≈6–8 µm. B) Spirochetes in blood smear...
• Figure 2. Immunoblot analysis of serum samples from 2 animals for Borrelia hermsi, Bitterroot Valley, Montana, USA. Samples were tested with B. hermsii whole cell lysates (WCL) (left lanes) and purified...
• Figure 3. Ornithodoros hermsi nymph collected from the property of a 55-year-old man with tickborne relapsing fever, Bitterroot Valley, Montana, USA. Scale bar = 0.5 mm.

Tables

• Table 1. Laboratory test results for serum from a 55-year-old man with tickborne relapsing fever on 2 dates compared with reference values, Montana, USA, 2013
• Table 2. Animals serologically analyzed for infection with Borrelia hermsi in 3 locations, Bitterroot Valley, Montana, USA, July 8–September 13, 2013

Suggested citation for this article: Christensen J, Fischer RJ, McCoy BN, Raffel SJ, Schwan TG. Tickborne relapsing fever, Bitterroot Valley, Montana, USA. Emerg Infect Dis. 2015 Feb [date cited]. http://dx.doi.org/10.3201/eid2102.141276

DOI: 10.3201/eid2102.141276