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Travelers' diarrhea: Microbiology, epidemiology, and prevention

Christine A Wanke, MD
Section Editor
Stephen B Calderwood, MD
Deputy Editor
Allyson Bloom, MD


Travelers' diarrhea is the most common illness in persons traveling from resource-rich to resource-limited regions of the world [1]. The fear of developing diarrhea while traveling is common among such travelers. This concern is realistic; 40 to 60 percent of travelers to these countries may develop diarrhea. Episodes of travelers' diarrhea are nearly always benign and self-limited, but the dehydration that can complicate an episode may be severe and pose a greater health hazard than the illness itself. Nevertheless, it is possible to educate a traveler to manage a diarrheal episode without compromising either their trip or their health.

The microbiology, epidemiology, and prevention of travelers' diarrhea are discussed here. The clinical manifestations, diagnosis, and treatment of travelers' diarrhea are discussed elsewhere. (See "Travelers' diarrhea: Clinical manifestations, diagnosis, and treatment".)


Travelers' diarrhea refers to diarrhea that develops during or within 10 days of returning from travel to resource-limited countries or regions. For epidemiological purposes, it is frequently categorized into three forms: classic, moderate, and mild. These forms of travelers' diarrhea are defined as follows [2]:

Classic — passage of three or more unformed stools in a 24 hour period plus at least one of these other symptoms: nausea, vomiting, abdominal pain or cramps, fever, blood in stools

Moderate — passage of one or two unformed stools in 24 hours plus at least one of the above symptoms or more than two unformed stools in 24 hours without other symptoms

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Literature review current through: Nov 2017. | This topic last updated: May 25, 2017.
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  1. Greenwood Z, Black J, Weld L, et al. Gastrointestinal infection among international travelers globally. J Travel Med 2008; 15:221.
  2. von Sonnenburg F, Tornieporth N, Waiyaki P, et al. Risk and aetiology of diarrhoea at various tourist destinations. Lancet 2000; 356:133.
  3. DuPont HL, Capsuto EG. Persistent diarrhea in travelers. Clin Infect Dis 1996; 22:124.
  4. DuPont HL, Ericsson CD. Prevention and treatment of traveler's diarrhea. N Engl J Med 1993; 328:1821.
  5. Steffen R, Collard F, Tornieporth N, et al. Epidemiology, etiology, and impact of traveler's diarrhea in Jamaica. JAMA 1999; 281:811.
  6. Adachi JA, Jiang ZD, Mathewson JJ, et al. Enteroaggregative Escherichia coli as a major etiologic agent in traveler's diarrhea in 3 regions of the world. Clin Infect Dis 2001; 32:1706.
  7. Shah N, DuPont HL, Ramsey DJ. Global etiology of travelers' diarrhea: systematic review from 1973 to the present. Am J Trop Med Hyg 2009; 80:609.
  8. Golledge CL, Riley TV. Clostridium difficile-associated diarrhoea after doxycycline malaria prophylaxis. Lancet 1995; 345:1377.
  9. Koo HL, Ajami NJ, Jiang ZD, et al. Noroviruses as a cause of diarrhea in travelers to Guatemala, India, and Mexico. J Clin Microbiol 2010; 48:1673.
  10. Apelt N, Hartberger C, Campe H, Löscher T. The Prevalence of Norovirus in returning international travelers with diarrhea. BMC Infect Dis 2010; 10:131.
  11. Goodgame R. Emerging Causes of Traveler's Diarrhea: Cryptosporidium, Cyclospora, Isospora, and Microsporidia. Curr Infect Dis Rep 2003; 5:66.
  12. Steffen R, Hill DR, DuPont HL. Traveler's diarrhea: a clinical review. JAMA 2015; 313:71.
  13. Schlagenhauf P, Weld L, Goorhuis A, et al. Travel-associated infection presenting in Europe (2008-12): an analysis of EuroTravNet longitudinal, surveillance data, and evaluation of the effect of the pre-travel consultation. Lancet Infect Dis 2015; 15:55.
  14. Mattila L, Siitonen A, Kyrönseppä H, et al. Seasonal variation in etiology of travelers' diarrhea. Finnish-Moroccan Study Group. J Infect Dis 1992; 165:385.
  15. Mattila L, Peltola H, Siitonen A, et al. Short-term treatment of traveler's diarrhea with norfloxacin: a double-blind, placebo-controlled study during two seasons. Clin Infect Dis 1993; 17:779.
  16. Centers for Disease Control and Prevention. Shigellosis related to an airplane meal - Northeastern U.S. MMWR 1971; 20:397.
  17. Hill DR, Beeching NJ. Travelers' diarrhea. Curr Opin Infect Dis 2010; 23:481.
  18. Black RE. Pathogens that cause travelers' diarrhea in Latin America and Africa. Rev Infect Dis 1986; 8 Suppl 2:S131.
  19. Soave R, Ma P. Cryptosporidiosis. Traveler's diarrhea in two families. Arch Intern Med 1985; 145:70.
  20. Jokipii L, Pohjola S, Jokipii AM. Cryptosporidiosis associated with traveling and giardiasis. Gastroenterology 1985; 89:838.
  21. Blake PA, Rosenberg ML, Florencia J, et al. Cholera in Portugal, 1974. II. Transmission by bottled mineral water. Am J Epidemiol 1977; 105:344.
  22. Adachi JA, Mathewson JJ, Jiang ZD, et al. Enteric pathogens in Mexican sauces of popular restaurants in Guadalajara, Mexico, and Houston, Texas. Ann Intern Med 2002; 136:884.
  23. Kantele A, Lääveri T, Mero S, et al. Antimicrobials increase travelers' risk of colonization by extended-spectrum betalactamase-producing Enterobacteriaceae. Clin Infect Dis 2015; 60:837.
  24. Rendi-Wagner P, Kollaritsch H. Drug prophylaxis for travelers' diarrhea. Clin Infect Dis 2002; 34:628.
  25. DuPont HL, Ericsson CD, Farthing MJ, et al. Expert review of the evidence base for prevention of travelers' diarrhea. J Travel Med 2009; 16:149.
  26. Alajbegovic S, Sanders JW, Atherly DE, Riddle MS. Effectiveness of rifaximin and fluoroquinolones in preventing travelers' diarrhea (TD): a systematic review and meta-analysis. Syst Rev 2012; 1:39.
  27. DuPont HL, Jiang ZD, Okhuysen PC, et al. A randomized, double-blind, placebo-controlled trial of rifaximin to prevent travelers' diarrhea. Ann Intern Med 2005; 142:805.
  28. Zanger P, Nurjadi D, Gabor J, et al. Effectiveness of rifaximin in prevention of diarrhoea in individuals travelling to south and southeast Asia: a randomised, double-blind, placebo-controlled, phase 3 trial. Lancet Infect Dis 2013; 13:946.
  29. Hilton E, Kolakowski P, Singer C, Smith M. Efficacy of Lactobacillus GG as a Diarrheal Preventive in Travelers. J Travel Med 1997; 4:41.
  30. Briand V, Buffet P, Genty S, et al. Absence of efficacy of nonviable Lactobacillus acidophilus for the prevention of traveler's diarrhea: a randomized, double-blind, controlled study. Clin Infect Dis 2006; 43:1170.
  31. Clemens JD, Sack DA, Harris JR, et al. Cross-protection by B subunit-whole cell cholera vaccine against diarrhea associated with heat-labile toxin-producing enterotoxigenic Escherichia coli: results of a large-scale field trial. J Infect Dis 1988; 158:372.
  32. Peltola H, Siitonen A, Kyrönseppä H, et al. Prevention of travellers' diarrhoea by oral B-subunit/whole-cell cholera vaccine. Lancet 1991; 338:1285.
  33. Wiedermann G, Kollaritsch H, Kundi M, et al. Double-blind, randomized, placebo controlled pilot study evaluating efficacy and reactogenicity of an oral ETEC B-subunit-inactivated whole cell vaccine against travelers' diarrhea (preliminary report). J Travel Med 2000; 7:27.
  34. Hill DR, Ford L, Lalloo DG. Oral cholera vaccines: use in clinical practice. Lancet Infect Dis 2006; 6:361.
  35. Behrens RH, Cramer JP, Jelinek T, et al. Efficacy and safety of a patch vaccine containing heat-labile toxin from Escherichia coli against travellers' diarrhoea: a phase 3, randomised, double-blind, placebo-controlled field trial in travellers from Europe to Mexico and Guatemala. Lancet Infect Dis 2014; 14:197.