Travelers' diarrhea

Diarrhoea is a major health problem during travel, affecting 10-50% of travelers. The term travelers' diarrhea defines a group of diseases that results from ingestion of food and water contaminated by infectious agents and has diarrhea as a major manifestation. In general travelers' diarrhea lasts two to three days, but can cause discomfort and prevent the realization of important activities. You can still develop complications like dehydration, which is more common in young children, the elderly and those with chronic diseases.
Treatment
The basic treatment of traveler's diarrhea and food poisoning consists of rehydration, which should be initiated as early as possible. In mild cases, rehydration may be administered orally, preferably with a rehydration solution containing electrolytes (salts) and glucose at suitable concentrations (ORS). The oral rehydration solution should be prepared immediately before consumption and the contents of an envelope must be dissolved in a liter of boiled water after cooling. The solution can not be boiled after prepared, but may be stored in refrigerator for up to 24 hours. It can be ingested in accordance with the acceptance, often proportional to the intensity and volume of diarrhea. Should be alternated with other liquids (water, tea, soup). The supply should be resumed after three to four hours of acceptance of oral rehydration and proper, in infants, breastfeeding should be maintained from the start. In children, should be avoided vomiting drugs, since they can cause intoxication, with decreased level of consciousness and involuntary movements, hindering the intake of oral rehydration solution. In addition, this drug is generally unnecessary since they tend to vomit with the top end of rehydration.
The use of any medication should be made only with medical supervision. The use of drugs such as antibiotics or antiparasitic, after medical evaluation may be indicated (or not) in diarrhea cases who develop fever, blood or pus in and manifested by a prolonged period of time. Antibiotics are not indicated in cases of food poisoning, since they do not act against toxins preformed. The use of agents that reduce intestinal motility (diphenoxylate, loperamide) for the symptomatic treatment of traveler's diarrhea is not recommended and is associated with the possibility of developing toxic megacolon (acute dilatation of all or part of the large intestine, potentially fatal). Drugs that act by reducing the secretion of fluid from the intestinal mucosa (such as bismuth subsalicylate) has slower onset of action, dosage appropriate bit (four doses per day), toxicity risk associated with salicylate and additionally may interfere with the absorption of antibiotics (as doxycycline). More severe cases should be hospitalized for intravenous hydration to the improvement of clinical conditions and the person as soon as possible, oral rehydration should be done simultaneously. In more pronounced diarrhea (in which cholera should be excluded) or more prolonged (lasting longer than three days), which evolve with the presence of blood or pus, or fever (which should be done in the differential diagnosis of typhoid and malaria ) a Health Service should be sought as soon as possible.

Prevention
The risk of travelers' diarrhea and food poisoning can be significantly reduced through the systematic adoption of protective measures against diseases transmitted by water and food. The food selection and consumption of safe drinking water is essential, though not simple tasks because they involve changes in individual risk perception, attitudes and habits. In general, the look, the smell and taste of food are not altered by contamination with infectious agents. To reduce risk, the traveler must feed themselves in places that have suitable conditions higênicas and observe extra care when selecting foods. The foods most at risk are poorly cooked or raw, such as salads, seafood, prepared with the eggs (such as mayonnaise, sauces, desserts like mousse), unpasteurized milk and dairy products (cheese, yogurt, cream), juices , ice cream and drinks (beats, caipirinhas) containing untreated water or ice. Food consumption exposed (as in buffets) at room temperature for long periods (hours), implies a high risk of disease. For this reason we should prefer the consumption of well-cooked or boiled food, freshly prepared and served in consumption still hot ("smoke out"). However, should not be consumed certain foods that are "made to order" (like burgers and sandwiches) when there is no assurance that the necessary products were stored at appropriate temperatures and locations. In this regard, it should be appreciated that the heating food preparation can further inactivate the toxin diarrhea, but does not destroy emetic toxins that cause food poisoning. In any country in the world, with food vendors should be avoided as it poses a high risk for acquiring disease.

In an area lacks infrastructure adequate sanitation, water for consumption should be treated by the traveler. The chemical treatment of water to be used as a beverage or in food preparation can be done with halogens (chlorine or iodine). Chlorine and iodine are capable of eliminating most infectious agents and have similar efficacy when used at concentrations and for time periods suitable. However, the oocysts of Cryptosporidium parvum (which can cause diarrhea in immunodeficient) are resistant to both. Moreover, it should be considered that iodine ingested with water may induce thyroid malfunction when used for long periods or in predisposed individuals. The iodinated compounds are absolutely contraindicated in pregnant women and people with thyroid diseases. The portable filters may be useful in the treatment of water for consumption and when the pores have diameters between 0.1 and 1 microM, remove most bacteria, protozoa and helminths, but do not eliminate the virus effectively. For this reason, the traveler must use filters impregnated previously with halogenated compounds or alternatively use chlorine (or iodine) after filtering. It is important to verify the manufacturer's instructions as to how many times it is possible to use safe filter.
The Cives does not recommend the systematic use of prophylactic antibiotics for travelers' diarrhea. Besides the high cost, antibiotics can cause significant adverse effects, such as photosensitivity (increased sensitivity of skin to sun), allergic reactions, abnormal intestinal microbiota (colonization by resistant bacteria, increasing the risk of typhoid), development of fungal infections as vaginal candidosis and risk of colitis (inflammatory bowel disease) caused by Clostridium difficile. The Cives also not recommended for use as routine, bismuth subsalicylate, since the dosage (four doses per day) is inconvenient and the risk of toxicity associated with the salicylate. The utility of probiotics (Lactobacillus like) to prevent travelers' diarrhea is not clearly defined.
There are no vaccines available against all infectious agents that cause travelers' diarrhea. E. Enterotoxigenic E. coli (ETEC) can produce two types of toxins, alone or in combination. A toxin is sensitive to heat (heat labile toxin) and the other is resistant (heat stable toxin). The oral vaccine against cholera, containing the B subunit of cholera toxin, recombinant may have a protective effect against cross travelers' diarrhea, solely when this is caused by Escherichia coli heat-sensitive toxin since the B subunit and thermolabile toxin are similar. The cross-protective effect may vary from place to place, according to the frequency of E. produdora coli heat labile toxin as a cause of travelers' diarrhea. In these circumstances, the effectiveness of oral vaccine against cholera, when considering all causes of travelers' diarrhea, is limited. For this reason, the Cives does not recommend the use of this vaccine when risk is considered to be exclusively travelers' diarrhea, except in situations of high individual risk of acquiring the disease (such as decreased gastric acidity) or in those in whom the consequences can be very serious (such as chronic renal failure, congestive heart failure, insulin-dependent diabetes, inflammatory bowel disease).
Always drink boiled or treated water and avoid salads and raw vegetables, especially when traveling.