View source for Medicine:Traveler's diarrhea

{{Infobox medical condition (new)
| name            = Traveler's diarrhea
| image           = E coli at 10000x, original.jpg
| caption         = The bacteria, E. coli, the most common cause of Traveler's diarrhea
| synonyms        = Traveller's diarrhoea, tourist diarrhea,<ref name=FNEncyc>{{Cite book|title = Foods & Nutrition Encyclopedia, Two Volume Set|url = |publisher = CRC Press|date = 1993-11-09|isbn = 9780849389801|first = Marion Eugene|last = Ensminger|first2 = Audrey H.|last2 = Ensminger|page = 143}}</ref> traveler's dysentery<ref name=FNEncyc />
| symptoms        = Unformed [[Medicine:Human feces|stool]] while traveling, fever, abdominal cramps<ref name=Gid2016/><ref name=AFP2015/>
| complications   = 
| onset           = 
| duration        = Typically < 5 days<ref name=AFP2015/>
| types           = 
| causes          = Often bacterial<ref name=AFP2015/>
| risks           = 
| diagnosis       = 
| differential    = 
| prevention      = Eating only properly prepared food, drinking bottled water, frequent hand washing<ref name=CDC2013/>
| treatment       = [[Medicine:Oral rehydration therapy|Oral rehydration therapy]], antibiotics, [[Chemistry:Loperamide|loperamide]]<ref name=AFP2015/><ref name=CDC2013/>
| medication      = 
| prognosis       = 
| frequency       = ~35% of travelers to the developing world<ref name=AFP2015/>
| deaths          = 
}}
<!-- Definition and symptoms -->
'''Traveler's diarrhea''' ('''TD''') is a stomach and intestinal infection. TD is defined as the passage of unformed [[Medicine:Human feces|stool]] (one or more by some definitions, three or more by others) while traveling.<ref name=Gid2016/><ref name=AFP2015/> It may be accompanied by abdominal cramps, nausea, fever, and bloating.<ref name=AFP2015/> Occasionally bloody diarrhea may occur.<ref>{{cite book| last1= Feldman| first1= Mark| title= Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management| date= 2015| publisher= Elsevier Health Sciences| isbn= 9781455749898| page= 1924| edition= 10th| url= https://books.google.com/books?id=4CMJBgAAQBAJ&pg=PA1924| deadurl= no| archiveurl= https://web.archive.org/web/20160310133204/https://books.google.com/books?id=4CMJBgAAQBAJ&pg=PA1924| archivedate= 2016-03-10| df= }}</ref> Most travelers recover within four days with little or no treatment.<ref name=AFP2015/> About 10% of people may have symptoms for a week.<ref name=AFP2015>{{cite journal|last1=Leder|first1=K|title=Advising travellers about management of travellers' diarrhoea.|journal=Australian family physician|date=2015|volume=44|issue=1–2|pages=34–37|pmid=25688957|url=http://www.racgp.org.au/afp/2015/januaryfebruary/advising-travellers-about-management-of-travellers%E2%80%99-diarrhoea/|deadurl=no|archiveurl=https://web.archive.org/web/20170112200909/http://www.racgp.org.au/afp/2015/januaryfebruary/advising-travellers-about-management-of-travellers%E2%80%99-diarrhoea|archivedate=2017-01-12|df=}}</ref>

<!-- Cause and diagnosis -->
[[Biology:Bacteria|Bacteria]] are responsible for more than half of cases.<ref name=AFP2015/> The bacteria [[Medicine:Enterotoxigenic Escherichia coli|enterotoxigenic ''Escherichia coli'']] (ETEC) are typically the most common except in [[Place:Southeast Asia|Southeast Asia]], where ''[[Biology:Campylobacter|Campylobacter]]'' is more prominent.<ref name=Gid2016/><ref name=AFP2015/> About 10% to 20% of cases are due to [[Medicine:Norovirus|norovirus]].<ref name=AFP2015/> [[Biology:Protozoa|Protozoa]] such as ''[[Biology:Giardia|Giardia]]'' may cause longer term disease.<ref name=AFP2015/> The risk is greatest in the first two weeks of travel and among young adults.<ref name=Gid2016/> People affected are more often from the developed world.<ref name=Gid2016/>

<!-- Prevention and treatment -->
Recommendations for prevention include eating only properly cleaned and cooked food, drinking bottled water, and frequent hand washing.<ref name=CDC2013/> The oral cholera vaccine, while effective for [[Medicine:Cholera|cholera]], is of questionable use for traveler's diarrhea.<ref name=Coch2013Duk>{{cite journal| last1= Ahmed| first1= T| last2= Bhuiyan| first2= TR| last3= Zaman| first3= K|last4=Sinclair|first4=D|last5=Qadri|first5=F|title=Vaccines for preventing enterotoxigenic Escherichia coli (ETEC) diarrhoea | journal= The Cochrane Database of Systematic Reviews|date=5 July 2013| volume= 7| pages= CD009029| pmid= 23828581| doi= 10.1002/14651858.CD009029.pub2}}</ref> Preventive [[Chemistry:Antibiotic|antibiotic]]s are generally discouraged.<ref name=AFP2015/> Primary treatment includes drinking lots of fluids and replacing lost salts ([[Medicine:Oral rehydration therapy|oral rehydration therapy]]).<ref name=AFP2015/><ref name=CDC2013/> Antibiotics are recommended for significant or persistent symptoms, and can be taken with [[Chemistry:Loperamide|loperamide]] to decrease diarrhea.<ref name=AFP2015/> Hospitalization is required in less than 3% of cases.<ref name=Gid2016/>

<!-- Epidemiology, prognosis, and culture -->
Estimates of the percentage of people affected range from 20 to 50% among travelers to the developing world.<ref name=AFP2015/> TD is particularly common among people travelling to Asia (except Japan), the Middle East, Africa, Mexico, and Central and South America.<ref name=CDC2013>{{cite web|url=http://wwwnc.cdc.gov/travel/page/travelers-diarrhea|date=April 26, 2013|title=Travelers' Diarrhea|work=cdc.gov|deadurl=no|archiveurl=https://web.archive.org/web/20160313100404/http://wwwnc.cdc.gov/travel/page/travelers-diarrhea|archivedate=March 13, 2016|df=}}</ref> The risk is moderate in [[Place:Southern Europe|Southern Europe]], Russia, and China.<ref>{{cite journal|last1=Diemert|first1=D. J.|title=Prevention and Self-Treatment of Traveler's Diarrhea|journal=Clinical Microbiology Reviews|date=17 July 2006|volume=19|issue=3|pages=583–594|doi=10.1128/CMR.00052-05}}</ref> TD has been linked to later [[Medicine:Irritable bowel syndrome|irritable bowel syndrome]] and [[Medicine:Guillain–Barré syndrome|Guillain–Barré syndrome]].<ref name=Gid2016>{{cite journal|last1=Giddings|first1=SL|last2=Stevens|first2=AM|last3=Leung|first3=DT|title=Traveler's Diarrhea |journal= The Medical clinics of North America|date=March 2016| volume= 100| issue= 2| pages= 317–30 |pmid= 26900116| doi= 10.1016/j.mcna.2015.08.017|pmc=4764790}}</ref><ref name=AFP2015/> It has colloquially been known by a number of names, including "Montezuma's revenge" and "Delhi belly".<ref name="webm_Trav">{{cite web | title = Traveler's Diarrhea-Topic Overview | work = WebMD | date = 2013-03-27 | accessdate = 2015-07-02 | url = http://www.webmd.com/a-to-z-guides/travelers-diarrhea-topic-overview | quote = Traveler's diarrhea is sometimes called by its more colorful names: Montezuma's revenge, Delhi belly, and Turkey trots. | deadurl = no | archiveurl = https://web.archive.org/web/20150630054521/http://www.webmd.com/a-to-z-guides/travelers-diarrhea-topic-overview | archivedate = 2015-06-30 | df =  }}</ref>

==Signs and symptoms==
The onset of TD usually occurs within the first week of travel, but may occur at any time while traveling, and even after returning home, depending on the incubation period of the infectious agent. Bacterial TD typically begins abruptly, but ''[[Biology:Cryptosporidium|Cryptosporidium]]'' may incubate for seven days, and ''[[Biology:Giardia|Giardia]]'' for 14 days or more, before symptoms develop.  Typically, a traveler experiences four to five loose or watery bowel movements each day. Other commonly associated symptoms are abdominal cramping, bloating, fever, and malaise.  Appetite may decrease significantly.<ref name="CDC_TD" />  Though unpleasant, most cases of TD are mild, and resolve in a few days without medical intervention.<ref name=SWOL-TD>{{cite web|url=http://www.safewateronline.com/travelers_d.htm|title=Travelers' diarrhea|publisher=safewateronline.com |archiveurl=https://web.archive.org/web/20080606032848/http://www.safewateronline.com/travelers_d.htm |archivedate = 6 June 2008}}</ref>

Blood or [[Biology:Mucus|mucus]] in the diarrhea, significant abdominal pain, or high fever suggests a more serious cause, such as [[Medicine:Cholera|cholera]], characterized by a rapid onset of weakness and torrents of watery diarrhea with flecks of mucus (described as "rice water" stools).  Medical care should be sought in such cases; dehydration is a serious consequence of cholera, and may trigger serious [[Medicine:Sequela|sequela]]e—including, in rare instances, death—as rapidly as 24 hours after onset if not addressed promptly.<ref name=SWOL-TD/>

==Causes==
{| class="wikitable" style = "float: right; margin-left:15px; text-align:center"
|-
| style="width:50%;"| ''E. coli'', enterotoxigenic
| style="width:50%;"| 20–75%
|-
| style="width:50%;"| ''E. coli'', enteroaggregative
| style="width:50%;"| 0–20%
|-
| style="width:50%;"| ''E. coli'', enteroinvasive
| style="width:50%;"| 0–6%
|-
| style="width:50%;"| ''[[Biology:Shigella|Shigella]]'' spp.
| style="width:50%;"| 2–30%
|-
| style="width:50%;"| ''[[Biology:Salmonella|Salmonella]]'' spp.
| style="width:50%;"| 0–33%
|-
| style="width:50%;"| ''[[Biology:Campylobacter jejuni|Campylobacter jejuni]]''
| style="width:50%;"| 3–17%
|-
| style="width:50%;"| ''Vibrio parahemolyticus''
| style="width:50%;"| 0–31%
|-
| style="width:50%;"| ''[[Biology:Aeromonas hydrophila|Aeromonas hydrophila]]''
| style="width:50%;"| 0–30%
|-
| style="width:50%;"| ''[[Biology:Giardia lamblia|Giardia lamblia]]''
| style="width:50%;"| 0–20%
|-
| style="width:50%;"| ''[[Biology:Entamoeba histolytica|Entamoeba histolytica]]''
| style="width:50%;"| 0–5%
|-
| style="width:50%;"| ''[[Biology:Cryptosporidium|Cryptosporidium]]'' spp.
| style="width:50%;"| 0–20%
|-
| style="width:50%;"| ''[[Biology:Cyclospora cayetanensis|Cyclospora cayetanensis]]''
| style="width:50%;"| ?
|-
| style="width:50%;"| ''[[Biology:Rotavirus|Rotavirus]]
| style="width:50%;"| 0–36%
|-
| style="width:50%;"| ''[[Medicine:Norovirus|Norovirus]]
| style="width:50%;"| 0–10%
|}
[[Biology:Pathogen|Infectious agent]]s are the primary cause of travelers' diarrhea. [[Biology:Enterobacteriaceae|Bacterial enteropathogens]] cause about 80% of cases.  Viruses and protozoans account for most of the rest.<ref name="CDC_TD"/>

The most common causative agent isolated in countries surveyed has been [[Medicine:Enterotoxigenic Escherichia coli|enterotoxigenic ''Escherichia coli'']] (ETEC).<ref name="CDC_TD"/> Enteroaggregative ''[[Biology:Escherichia coli|E. coli]]'' is increasingly recognized.<ref name=SWOL-TD/> ''[[Biology:Shigella|Shigella]]'' spp. and ''[[Biology:Salmonella|Salmonella]]'' spp. are other common bacterial pathogens.  ''[[Biology:Campylobacter|Campylobacter]]'', ''[[Biology:Yersinia|Yersinia]]'', ''[[Biology:Aeromonas|Aeromonas]]'', and ''Plesiomonas'' spp. are less frequently found.  Mechanisms of action vary: some bacteria release [[Biology:Toxin|toxin]]s which bind to the intestinal wall and cause diarrhea; others damage the intestines themselves by their direct presence.

While viruses are associated with less than 20% of adult cases of traveler's diarrhea, they may be responsible for nearly 70% of cases in infants and children. Diarrhea due to viral agents is unaffected by antibiotic therapy, but is usually self-limited.<ref name=SWOL-TD/>  Protozoans such as ''[[Biology:Giardia lamblia|Giardia lamblia]]'', ''[[Biology:Cryptosporidium|Cryptosporidium]]'' and ''[[Biology:Cyclospora cayetanensis|Cyclospora cayetanensis]]'' can also cause diarrhea. Pathogens commonly implicated in travelers' diarrhea appear in the table in this section.<ref name=SWOL-TD/><ref name="ncbi.nlm.nih.gov">{{cite journal |last1=Ortega |first1=Ynés R. |last2=Sanchez |first2=Roxana |title=Update on ''Cyclospora cayetanensis'', a Food-Borne and Waterborne Parasite |journal=Clinical Microbiology Reviews |volume=23 |issue=1 |pages=218–234 |doi=10.1128/CMR.00026-09 |pmc=2806662 |pmid=20065331 |year=2010}}</ref>

A subtype of traveler's diarrhea afflicting hikers and campers, sometimes known as wilderness diarrhea, may have a somewhat different frequency of distribution of pathogens.<ref name="Zell1992" />

===Risk factors===
The primary source of infection is ingestion of fecally contaminated food or water. Attack rates are similar for men and women.<ref name="CDC_TD" />

The most important determinant of risk is the traveler's destination. High-risk destinations include [[Finance:Developing country|developing countries]] in Latin America, Africa, the Middle East, and Asia.<ref name="CDC_TD" /> Among backpackers, additional risk factors include drinking untreated surface water and failure to maintain personal hygiene practices and clean cookware.<ref name="pmid16805145">{{cite journal |author=Hargreaves JS |title=Laboratory evaluation of the 3-bowl system used for washing-up eating utensils in the field |journal=Wilderness Environ Med |volume=17 |issue=2 |pages=94–102 |year=2006 |pmid=16805145 |doi= 10.1580/PR17-05.1|url=http://www.wemjournal.org/article/S1080-6032(06)70296-4/fulltext |location=Diarrhea is a common illness of wilderness travelers, occurring in about one third of expedition participants and participants on wilderness recreation courses. The incidence of diarrhea may be as high as 74% on adventure trips. …Wilderness diarrhea is not caused solely by waterborne pathogens, … poor hygiene, with fecal-oral transmission, is also a contributing factor |format=}}</ref> Campsites often have very primitive (if any) sanitation facilities, making them potentially as dangerous as any developing country.

Although traveler's diarrhea usually resolves within three to five days (mean duration: 3.6 days), in about 20% of cases, the illness is severe enough to require bedrest, and in 10%, the illness duration exceeds one week.<ref name=SWOL-TD/>  For those prone to serious infections, such as  bacillary dysentery, amoebic dysentery, and [[Medicine:Cholera|cholera]], TD can occasionally be life-threatening.<ref name=SWOL-TD/>  Others at higher-than-average risk include young adults, [[Biology:Immunosuppression|immunosuppressed]] persons, persons with [[Medicine:Inflammatory bowel disease|inflammatory bowel disease]] or [[Medicine:Diabetes|diabetes]], and those taking [[Chemistry:H2 antagonist|H2 blockers]] or antacids.<ref name="CDC_TD"/>

===Immunity===
Travelers often get diarrhea from eating and drinking foods and beverages that have no adverse effects on local residents. This is due to [[Medicine:Immunity (medical)|immunity]] that develops with constant, repeated exposure to pathogenic organisms. The extent and duration of exposure necessary to acquire immunity has not been determined; it may vary with each individual organism. A study among expatriates in Nepal suggests that immunity may take up to seven years to develop—presumably in adults who avoid deliberate pathogen exposure.<ref>David R. Shlim, [http://www.ciwec-clinic.com/diar/index.html#9 Understanding Diarrhea in Travelers. A Guide to the Prevention, Diagnosis, and Treatment of the World's Most Common Travel-Related Illness] {{webarchive|url=https://web.archive.org/web/20080524201811/http://www.ciwec-clinic.com/diar/index.html |date=2008-05-24 }}. CIWEC Clinic Travel Medicine Center, 2004.</ref>
Conversely, immunity acquired by American students while living in Mexico disappeared, in one study, as quickly as eight weeks after cessation of exposure.<ref name="ostrosky">Luis Ostrosky-Zeichner, Charles D. Ericsson,
''Travelers' diarrhea''. In Jane N. Zucherman, Ed., ''Principles and Practice of Travel Medicine'', John Wiley and Sons, 2001. p.153
[https://books.google.com/books?id=QLSsRQYRV-8C&pg=PA153 Google books preview] {{webarchive|url=https://web.archive.org/web/20170908185632/https://books.google.com/books?id=QLSsRQYRV-8C&pg=PA153 |date=2017-09-08 }}</ref>

==Prevention==

===Sanitation===
Recommendations include avoidance of questionable foods and drinks, on the assumption that TD is fundamentally a [[Engineering:Sanitation|sanitation]] failure, leading to bacterial contamination of drinking water and food.<ref name="CDC_TD" /> While the effectiveness of this strategy has been questioned, given that travelers have little or no control over sanitation in hotels and restaurants, and little evidence supports the contention that food vigilance reduces the risk of contracting TD,<ref name="CID-CHL">{{cite journal|last1=Shlim|first1=DR|title=Looking for evidence that personal hygiene precautions prevent traveler's diarrhea.|journal=Clinical Infectious Diseases|date=1 December 2005|volume=41 Suppl 8|pages=S531-5|pmid=16267714|doi=10.1086/432947}}</ref> guidelines continue to recommend basic, common-sense precautions when making food and beverage choices:<ref name=AFP2015/>

* Maintain good hygiene and use only safe water for drinking and brushing teeth.<ref name=SWOL-TD/>
* Safe beverages include bottled water, bottled carbonated beverages, and water boiled or appropriately treated by the traveler (as described below).<ref name=SWOL-TD/> Caution should be exercised with tea, coffee, and other hot beverages that may be only heated, not boiled.<ref name="CDC_TD" />
* In restaurants, insist that bottled water be unsealed in your presence; reports of locals filling empty bottles with untreated tap water and reselling them as purified water have surfaced.<ref name=SWOL-TD/> When in doubt, a bottled carbonated beverage is the safest choice, since it is difficult to simulate carbonation when refilling a used bottle.
* Avoid ice, which may not have been made with safe water.<ref name="CDC_TD" />
* Avoid green salads, because the lettuce and other uncooked ingredients are unlikely to have been washed with safe water.<ref name="CDC_TD" />
* Avoid eating raw fruits and vegetables unless cleaned and peeled personally.<ref name="CDC_TD" />

If handled properly, thoroughly cooked fresh and packaged foods are usually safe.<ref name="CDC_TD" /> Raw or undercooked meat and seafood should be avoided. [[Chemistry:Pasteurization|Unpasteurized]] milk, dairy products, mayonnaise, and pastry icing are associated with increased risk for TD, as are foods and beverages purchased from street vendors and other establishments where unhygienic conditions may be present.<ref name=SWOL-TD/>

===Water===
Although safe bottled water is now widely available in most remote destinations, travelers can treat their own water if necessary, or as an extra precaution.<ref name=SWOL-TD/> 
Techniques include boiling, filtering, chemical treatment, and ultraviolet light; boiling is by far the most effective of these methods.<ref>https://wwwnc.cdc.gov/travel/yellowbook/2018/the-pre-travel-consultation/water-disinfection-for-travelers</ref> Boiling rapidly kills all active bacteria, viruses, and protozoa. Prolonged boiling is usually unnecessary; most microorganisms are killed within seconds at water temperature above 55–70&nbsp;°C (130–160&nbsp;°F).<ref>National Advisory Committee on Microbiological Criteria for Foods: Requisite Scientific Parameters for Establishing the Equivalence of Alternative Methods of Pasteurization, USDA, 2004</ref><ref>{{cite web |url=http://www.nytimes.com/2011/08/24/dining/bending-the-rules-on-bacteria-and-food-safety.html?pagewanted=all&_r=0 |title=Archived copy |accessdate=2014-10-24 |deadurl=bot: unknown |archiveurl=https://web.archive.org/web/20170908185621/http://www.nytimes.com/2011/08/24/dining/bending-the-rules-on-bacteria-and-food-safety.html?pagewanted=all&_r=0 |archivedate=2017-09-08 |df= }}. Retrieved October 24, 2014.</ref> The second-most effective method is to combine filtration and chemical disinfection.<ref>https://www.cdc.gov/healthywater/pdf/drinking/Backcountry_Water_Treatment.pdf</ref>  Filters eliminate most bacteria and protozoa, but not viruses. Chemical treatment with halogens—chlorine bleach, tincture of iodine, or commercial tablets—have low-to-moderate effectiveness against protozoa such as ''Giardia'', but work well against bacteria and viruses. 
UV light is effective against both viruses and cellular organisms, but only works in clear water, and it is ineffective unless manufacturer's instructions are carefully followed for maximum water depth/distance from UV source, and for dose/exposure time. Other claimed advantages include short treatment time, elimination of the need for boiling, no taste alteration, and decreased long-term cost compared with bottled water.  The effectiveness of UV devices is reduced when water is muddy or turbid; as UV is a type of light, any suspended particles create shadows that hide microorganisms from UV exposure.<ref>''Ultraviolet Light Disinfection in the Use of Individual Water Purification Devices''. Technical Information Paper # 31-006-0211 [http://phc.amedd.army.mil/PHC%20Resource%20Library/Ultraviolet%20Light%20Disinfection%20in%20the%20Use%20of%20Individual%20Water%20Purification%20Devices.pdf U.S. Army Public Health Command] {{webarchive|url=https://web.archive.org/web/20140308021004/http://phc.amedd.army.mil/PHC%20Resource%20Library/Ultraviolet%20Light%20Disinfection%20in%20the%20Use%20of%20Individual%20Water%20Purification%20Devices.pdf |date=2014-03-08 }}, retrieved January 5, 2016.</ref>

===Medications===
Other preventive options include [[Medicine:Over-the-counter drug|over-the-counter]] antidiarrhea products and antibiotics.

[[Chemistry:Bismuth subsalicylate|Bismuth subsalicylate]] four times daily reduces rates of traveler's diarrhea.<ref name=Gid2016/><ref name=Du2009/> Though many travelers find a four-times-per-day regimen inconvenient, lower doses have not been shown to be effective.<ref name=Gid2016/><ref name=Du2009/> Potential side effects include black tongue, black stools, nausea, constipation, and [[Medicine:Tinnitus|ringing in the ears]]. Bismuth subsalicylate should not be taken by those with [[Chemistry:Aspirin|aspirin]] allergy, kidney disease, or [[Medicine:Gout|gout]], nor concurrently with certain antibiotics such as the quinolones, and should not be taken continuously for more than three weeks.{{mcn|date=June 2017}}  Some countries do not recommend it due to the risk of rare but serious side effects.<ref name=Du2009/>

A [[Biology:Colostrum#Hyperimmune colostrum|hyperimmune bovine colostrum]] to be taken by mouth is marketed in Australia for prevention of ETEC-induced TD.<!-- <ref name=AFP2015/> --> As yet, no studies show efficacy under actual travel conditions.<ref name=AFP2015/>

Though effective, antibiotics are not recommended for prevention of TD in most situations because of the risk of allergy or adverse reactions to the antibiotics, and because intake of preventive antibiotics may decrease effectiveness of such drugs should a serious infection develop subsequently. Antibiotics can also cause vaginal yeast infections, or overgrowth of the bacterium ''Clostridium difficile'', leading to pseudomembranous colitis and its associated severe, unrelenting diarrhea.<ref>Travelers' Diarrhea. [http://www.travdoc.com/articles/28.html The Travel Doctor] {{webarchive|url=https://web.archive.org/web/20110201035514/http://www.travdoc.com/articles/28.html |date=2011-02-01 }} Retrieved March 21, 2011.</ref>

Antibiotic prophylaxis may be warranted in special situations where benefits outweigh the above risks, such as immunocompromised travelers, chronic intestinal disorders, prior history of repeated disabling bouts of TD, or scenarios in which the onset of diarrhea might prove particularly troublesome. Options for prophylactic treatment include the quinolone antibiotics (such as [[Chemistry:Ciprofloxacin|ciprofloxacin]]), [[Chemistry:Azithromycin|azithromycin]], and trimethoprim/sulfamethoxazole, though the latter has proved less effective in recent years.<ref>Adachi J, et al. Empirical Antimicrobial Therapy for Traveler's Diarrhea. ''Clinical Infectious Diseases''; Vol. 31 Issue 4 (10/1/2000), p1079.</ref>  [[Chemistry:Rifaximin|Rifaximin]] may also be useful.<ref name=Du2009/><ref>{{cite journal | author=DuPont, H | title=Therapy for and Prevention of Traveler's Diarrhea | journal= Clinical Infectious Diseases | issue=45 (Suppl 1) | pages=S78–S84 | year=2007 | doi=10.1086/518155 | volume=45 | pmid=17582576 }}</ref>  Quinolone antibiotics may bind to metallic cations such as bismuth, and should not be taken concurrently with bismuth subsalicylate. Trimethoprim/sulfamethoxazole should not be taken by anyone with a history of [[Medicine:Sulfonamide|sulfa]] allergy.{{mcn|date=June 2017}}

===Vaccination===
The oral cholera vaccine, while effective for prevention of cholera, is of questionable use for prevention of TD.<ref name=Coch2013Duk/> A 2008 review found tentative evidence of benefit.<ref>{{cite journal |vauthors=Jelinek T, Kollaritsch H | year = 2008 | title = Vaccination with Dukoral against travelers' diarrhea (ETEC) and cholera | url = | journal = Expert Rev Vaccines | volume = 7 | issue = 5| pages = 561–7 | doi = 10.1586/14760584.7.5.561 | pmid = 18564011 }}</ref> A 2015 review stated it may be reasonable for those at high risk of complications from TD.<ref name=AFP2015/> Several vaccine candidates targeting ETEC or ''Shigella'' are in various stages of development.<ref>[http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index4.html World Health Organization. Enterotoxigenic ''Escherichia coli'' (ETEC).] {{webarchive|url=https://web.archive.org/web/20120515142857/http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index4.html |date=2012-05-15 }}</ref><ref>{{cite web|url=http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index6.html|title=World Health Organization. Shigellosis.|work=who.int|deadurl=no|archiveurl=https://web.archive.org/web/20081215123745/http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index6.html|archivedate=2008-12-15|df=}}</ref>

===Probiotics===
One 2007 review found that probiotics may be safe and effective for prevention of TD, while another review found no benefit.<ref name=Gid2016/> A 2009 review confirmed that more study is needed, as the evidence to date is mixed.<ref name=Du2009>{{cite journal|last1=DuPont|first1=HL|last2=Ericsson|first2=CD|last3=Farthing|first3=MJ|last4=Gorbach|first4=S|last5=Pickering|first5=LK|last6=Rombo|first6=L|last7=Steffen|first7=R|last8=Weinke|first8=T|title=Expert review of the evidence base for prevention of travelers' diarrhea.|journal=Journal of travel medicine|date=2009|volume=16|issue=3|pages=149–60|pmid=19538575|doi=10.1111/j.1708-8305.2008.00299.x}}</ref>

==Treatment==
Most cases of TD are mild and resolve in a few days without treatment, but severe or protracted cases may result in significant fluid loss and dangerous electrolytic imbalance. Dehydration due to diarrhea can also alter the effectiveness of medicinal and contraceptive drugs. Adequate fluid intake ([[Medicine:Oral rehydration therapy|oral rehydration therapy]]) is therefore a high priority. Commercial rehydration drinks<ref>Rehydration drinks. [http://www.emedicinehealth.com/script/main/art.asp?articlekey=134087&ref=126852 EMedicineHealth.com.] {{webarchive|url=https://web.archive.org/web/20140819091348/http://www.emedicinehealth.com/script/main/art.asp?articlekey=134087&ref=126852 |date=2014-08-19 }} Retrieved August 18, 2014.</ref> are widely available; alternatively, purified water or other clear liquids are recommended, along with salty crackers or oral rehydration salts (available in stores and pharmacies in most countries) to replenish lost electrolytes.<ref name="CDC_TD"/> Carbonated water or soda, left open to allow dissipation of the carbonation, is useful when nothing else is available.<ref name=SWOL-TD/>  In severe or protracted cases, the oversight of a medical professional is advised.

===Antibiotics===
If diarrhea becomes severe (typically defined as three or more loose stools in an eight-hour period), especially if associated with nausea, vomiting, abdominal cramps, fever, or blood in stools, medical treatment should be sought. Such patients may benefit from antimicrobial therapy.<ref name="CDC_TD"/>  A 2000 literature review found that antibiotic treatment shortens the duration and severity of TD; most reported side effects were minor, or resolved on stopping the antibiotic.<ref>{{cite journal |vauthors=De Bruyn G, Hahn S, Borwick A | year = 2000 | title = Antibiotic treatment for travellers' diarrhoea | url = | journal = Cochrane Database of Systematic Reviews | volume =  | issue = 3 | page = CD002242 | doi = 10.1002/14651858.CD002242 }}</ref>

Fluoroquinolone antibiotics are the drugs of choice. Trimethoprim–sulfamethoxazole and [[Chemistry:Doxycycline|doxycycline]] are no longer recommended because of high levels of resistance to these agents.<ref name="CDC_TD"/>  Antibiotics are typically given for three to five days, but single doses of [[Chemistry:Azithromycin|azithromycin]] or [[Chemistry:Levofloxacin|levofloxacin]] have been used.<ref>{{cite journal |author=Sanders JW |title=Azithromycin and loperamide are comparable to levofloxacin and loperamide for the treatment of traveler's diarrhea in United States military personnel in Turkey |journal=Clin. Infect. Dis. |volume=45 |issue=3 |pages=294–301 |date=August 2007 |pmid=18688944 |doi=10.1086/519264 |url=http://www.journals.uchicago.edu/doi/abs/10.1086/519264 |name-list-format=vanc|author2=Frenck RW |author3=Putnam SD |display-authors=3 |last4=Riddle |first4=M. S. |last5=Johnston |first5=J. R. |last6=Ulukan |first6=S. |last7=Rockabrand |first7=D. M. |last8=Monteville |first8=M. R. |last9=Tribble |first9=D. R.}}</ref>  [[Chemistry:Rifaximin|Rifaximin]] is approved in the U.S. for treatment of TD caused by ETEC.<ref>{{cite web|url= http://www.fda.gov/cder/foi/label/2007/021361s006lbl.pdf |title=Xifaxan label information }} Retrieved November 15, 2008.</ref>  If diarrhea persists despite therapy, travelers should be evaluated for bacterial strains resistant to the prescribed antibiotic, possible viral or parasitic infections,<ref name="CDC_TD"/> bacterial or amoebic dysentery, ''Giardia'', helminths, or cholera.<ref name=SWOL-TD/>

===Antimotility agents===
Antimotility drugs such as [[Chemistry:Loperamide|loperamide]] and [[Chemistry:Diphenoxylate|diphenoxylate]] reduce the symptoms of diarrhea by slowing transit time in the gut.  They may be taken to slow the frequency of stools, but not enough to stop bowel movements completely, which delays expulsion of the causative organisms from the intestines.<ref name="CDC_TD"/> They should be avoided in patients with fever, bloody diarrhea, and possible inflammatory diarrhea.<ref>{{cite web |url=http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/gastroenterology/acute-diarrhea/Default.htm |title=Archived copy |accessdate=2015-07-25 |deadurl=no |archiveurl=https://web.archive.org/web/20160304030320/http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/gastroenterology/acute-diarrhea/Default.htm |archivedate=2016-03-04 |df= }}</ref> Adverse reactions may include nausea, vomiting, abdominal pain, hives or rash, and loss of appetite.<ref>Diphenoxylate package insert. [https://www.drugs.com/mmx/lomotil.html Drugs.com.] {{webarchive|url=https://web.archive.org/web/20110622133643/http://www.drugs.com/mmx/lomotil.html |date=2011-06-22 }} Retrieved 2010-10-07.</ref> Antimotility agents should not, as a rule, be taken by children under age two.{{mcn|date=June 2017}}

==Epidemiology==
An estimated 10 million people—20 to 50% of international travelers—develop TD each year.<ref name=CDC_TD>{{cite web |title=Travelers' Diarrhea |url=https://www.cdc.gov/ncidod/dbmd/diseaseinfo/travelersdiarrhea_g.htm |date=November 21, 2006 |publisher=Centers for Disease Control and Prevention |deadurl=no |archiveurl=https://web.archive.org/web/20080403234924/http://www.cdc.gov/NCIDOD/DBMD/DISEASEINFO/travelersdiarrhea_g.htm |archivedate=April 3, 2008 |df= }}</ref>  It is more common in the developing world, where rates exceed 60%, but has been reported in some form in virtually every travel destination in the world.<ref name=Epi05>{{cite journal|last=Steffen|first=R|title=Epidemiology of traveler's diarrhea|journal=Clinical Infectious Diseases|date=Dec 1, 2005|volume=41 Suppl 8|pages=S536–40|pmid=16267715|doi=10.1086/432948}}</ref>

==Society and culture==
''Montezuma's revenge'' (var. ''Moctezuma's revenge'') is a colloquial term for traveler's diarrhea contracted in Mexico. The name refers to Moctezuma II (1466–1520), the Tlatoani (ruler) of the Aztec civilization who was overthrown by the Spanish conquistador Hernán Cortés in the early 16th century, thereby bringing large portions of what is now Mexico and Central America under the rule of the Spanish crown.

===Wilderness diarrhea===
Wilderness diarrhea, also called wilderness-acquired diarrhea (WAD) or backcountry diarrhea, refers to diarrhea among backpackers, hikers, campers and other outdoor recreationalists in wilderness or backcountry situations, either at home or abroad.<ref name="Zell1992">{{cite journal |author=Zell SC |title=Epidemiology of Wilderness-acquired Diarrhea: Implications for Prevention and Treatment |journal=J Wilderness Med |volume=3 |issue=3 |pages=241–9 |year=1992 |url=http://www.wemjournal.org/article/S0953-9859(92)71235-2/pdf |doi=10.1580/0953-9859-3.3.241}}</ref>  It is caused by the same fecal microorganisms as other forms of traveler's diarrhea, usually bacterial or viral.  Since wilderness campsites seldom provide access to sanitation facilities, the infection risk is similar to that of any developing country.<ref name="pmid16805145"/>  Water treatment, good hygiene, and dish washing have all been shown to reduce the incidence of WAD.<ref>{{cite journal|last1=Boulware|first1=DR|title=Medical risks of wilderness hiking|journal=American Journal of Medicine|date=2003|issue=March|pmid=12681456|volume=114|pages=288–93|doi=10.1016/S0002-9343(02)01494-8}}</ref><ref>{{cite journal|last1=McIntosh|first1=SE|title=Medical Incidents and Evacuations on Wilderness Expeditions|journal=Wilderness and Environmental Medicine|date=2007|issue=Winter|pmid=18076301|doi=10.1580/07-WEME-OR-093R1.1|volume=18|pages=298–304}}</ref>

==References==
{{CDC}}
{{Reflist}}

== External links ==
{{Medical resources
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{{Wikivoyage|Travellers' diarrhea}}

{{Bacterial diseases}}

{{DEFAULTSORT:Traveler's Diarrhea}}
[[Category:Infectious diseases]]

{{Sourceattribution|Traveler's diarrhea|1}}