World Library  
Flag as Inappropriate
Email this Article

Relapsing fever

Article Id: WHEBN0004893797
Reproduction Date:

Title: Relapsing fever  
Author: World Heritage Encyclopedia
Language: English
Subject: List of MeSH codes (C01), Willy Burgdorfer, List of notifiable diseases, Disease surveillance, Jarisch–Herxheimer reaction
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Relapsing fever

Relapsing fever is a vector-borne disease caused by infection with certain bacteria in the genus Borrelia,[1] which are transmitted through the bites of lice or soft-bodied ticks (genus Ornithodoros).[2]

Contents

  • Signs and symptoms 1
  • Causes 2
    • Louse-borne relapsing fever 2.1
    • Tick-borne relapsing fever 2.2
  • Diagnosis 3
  • Treatment 4
  • Vaccine research 5
  • History 6
  • See also 7
  • References 8
  • External links 9

Signs and symptoms

Most people who are infected develop sickness between five and 15 days after they are bitten. The symptoms may include a sudden fever, chills, headaches, muscle or joint aches, and nausea. A rash may also occur. These symptoms usually continue for two to 9 days, then disappear. This cycle may continue for several weeks if the person is not treated.[3]

Causes

Louse-borne relapsing fever

Along with Rickettsia prowazekii and Bartonella quintana, Borrelia recurrentis is one of three pathogens of which the body louse (Pediculus humanus humanus) is a vector.[4] Louse-borne relapsing fever is more severe than the tick-borne variety.

Louse-borne relapsing fever occurs in epidemics amid poor living conditions, famine and war in the developing world.[5] It is currently prevalent in Ethiopia and Sudan.

Mortality rate is 1% with treatment and 30–70% without treatment. Poor prognostic signs include severe jaundice, severe change in mental status, severe bleeding and a prolonged QT interval on ECG.

Lice that feed on infected humans acquire the Borrelia organisms that then multiply in the gut of the louse. When an infected louse feeds on an uninfected human, the organism gains access when the victim crushes the louse or scratches the area where the louse is feeding. B. recurrentis infects the person via mucous membranes and then invades the bloodstream. No non-human, animal reservoir exists.

Tick-borne relapsing fever

Tick-borne relapsing fever is found primarily in Africa, Spain, Saudi Arabia, Asia, and certain areas of Canada and the western United States. Other relapsing infections are acquired from other Borrelia species, which can be spread from rodents, and serve as a reservoir for the infection, by a tick vector.

B. hermsii and B. recurrentis cause very similar diseases. However, one or two relapses are common with the disease associated with B. hermsii, which is also the most common cause of relapsing disease in the United States. (Three or four relapses are common with the disease caused by B. recurrentis, which has longer febrile and afebrile intervals and a longer incubation period than B. hermsii.)

Diagnosis

Relapsing fever is a candidate etiology for a mysterious series of plagues in late-Medieval and early-Renaissance England. At the time, they were called sweating sicknesses. They have not recurred in epidemic form since the 16th century.

The diagnosis of relapsing fever can be made on blood smear as evidenced by the presence of spirochetes. Other spirochete illnesses (Lyme disease, syphilis, leptospirosis) do not show spirochetes on blood smear.

Treatment

Relapsing fever is easily treated with a one- to two-week-course of antibiotics, and most people improve within 24 hours. Complications and death due to relapsing fever are rare.

Tetracycline-class antibiotics are most effective. These can, however, induce a Jarisch–Herxheimer reaction in over half those treated, producing anxiety, diaphoresis, fever, tachycardia and tachypnea with an initial pressor response followed rapidly by hypotension. Recent studies have shown tumor necrosis factor-alpha may be partly responsible for this reaction.

Vaccine research

Currently, no vaccine against relapsing fever is available, but research is on-going. Developing a vaccine is very difficult because the spirochetes avoid the immune response of the infected person (or animal) through antigenic variation. Essentially, the pathogen stays one step ahead of antibodies by changing its surface proteins. These surface proteins, lipoproteins called variable major proteins, have only 30–70% of their amino acid sequences in common, which is sufficient to create a new antigenic "identity" for the organism. Antibodies in the blood that are binding to and clearing spirochetes expressing the old proteins do not recognize spirochetes expressing the new ones. Antigenic variation is common among pathogenic organisms. These include the agents of malaria, gonorrhea, and sleeping sickness. Important questions about antigenic variation are also relevant for such research areas as developing a vaccine against HIV and predicting the next influenza pandemic.

History

The physician David Livingstone is credited with the first account in 1857 of a malady associated with the bite of soft ticks in Angola and Mozambique.[7] In 1904 and 1905, a series of papers outlined the cause of relapsing fever and its relationship with ticks.[8][9][10][11] Both Joseph Everett Dutton and John Lancelot Todd contracted relapsing fever by performing autopsies while working in the eastern region of the Congo Free State. Dutton died there on February 27, 1905. The cause of tick-borne relapsing fever across central Africa was named Spirillum duttoni.[12] In 1984, it was renamed Borrelia duttoni.[13]

Sir William MacArthur suggested that relapsing fever was the cause of the yellow plague, variously called pestis flava, pestis ictericia, buidhe chonaill, or cron chonnaill, which struck early Medieval Britain and Ireland, and of epidemics which struck modern Ireland in the famine.[14][15]

See also

References

  1. ^ Schwan T (1996). "Ticks and Borrelia: model systems for investigating pathogen-arthropod interactions". Infect Agents Dis 5 (3): 167–81.  
  2. ^ Schwan T, Piesman J; Piesman (2002). "Vector interactions and molecular adaptations of Lyme disease and relapsing fever spirochetes associated with transmission by ticks". Emerg Infect Dis 8 (2): 115–21.  
  3. ^ Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. pp. 432–4.  
  4. ^ Fournier, Pierre-Edouard. "Human Pathogens in Body and Head Lice". Retrieved October 17, 2010. 
  5. ^ Cutler S (2006). "Possibilities for relapsing fever reemergence". Emerg Infect Dis 12 (3): 369–74.  
  6. ^ McNeil, Donald (19 September 2011). "New Tick-Borne Disease Is Discovered". The New York Times. pp. D6. Retrieved 20 September 2011. 
  7. ^ Livingstone D (1857) Missionary travels and researches in South Africa. London: John Murray
  8. ^ Cook AR (1904). "Relapsing fever in Uganda". J Trop Med Hyg 7: 24–26. 
  9. ^ Ross, P. H.; Milne, A. D. (1904). ""Tick Fever."". British medical journal 2 (2291): 1453–4.  
  10. ^ Dutton JE, Todd JL (1905). "The nature of human tick-fever in the eastern part of the Congo Free State with notes on the distribution and bionomics of the tick". Liverpool School Trop Med Mem 17: 1–18. 
  11. ^ Wellman FC (1905). "Case of relapsing fever, with remarks on its occurrence in the tropics and its relation to "tick fever"". J Trop Med 8: 97–99. 
  12. ^ Novy, F. G.; Knapp, R. E. (1906). and related organisms"Spirillum obermeieri"Studies on . Journal of Infectious Diseases 3 (3): 291.  
  13. ^ Kelly RT (1984) "Genus IV. Borrelia Swellengrebel 1907" in Krieg NR (ed.) Bergey's Manual of Systematic Bacteriology. Baltimore: Williams & Wilkins
  14. ^ Bonser, Wilfrid and MacArthur, Sir Wm (1944). "Epidemics during the Anglo-Saxon period, with appendix: Famine fevers in England and Ireland". Journal of the British Archaeological Association 9: 48–71. 
  15. ^ MacArthur, W (1947). "Famine fevers in England and Ireland". Postgraduate medical journal 23 (260): 283–6.  

External links

  • CDC: Relapsing Fever
  • Scientist and astronomer Larry Webster infected with relapsing fever
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.