WATER
In areas with poor sanitation only the following beverages may be safe to drink: Boiled water, hot beverages, such as coffee or tea, made with boiled water, canned or bottled carbonated beverages, beer, and wine. Ice may be made from unsafe water and should be avoided. It is safer to drink from a can or bottle of beverage than to drink from a container that was not known to be clean and dry. However, water on the surface of a beverage can or bottle may also be contaminated. Therefore, the area of a can or bottle that will touch the mouth should be wiped clean and dry. Where water is contaminated, travelers should not brush their teeth with tap water.
TREATMENT OF WATER
Boiling is the most reliable method to make water safe to
drink. Bring water to a vigorous boil, then allow it to cool; do not add ice. At high altitudes allow water to boil vigorously for a few minutes or use chemical disinfectants. Adding a pinch of salt or pouring water from one container to another will improve the taste.
Chemical disinfection can be achieved with either iodine or chlorine, with iodine providing greater disinfection in a wider set of circumstances. For disinfection with iodine use either tincture of iodine or tetraglycine hydroperiodide tablets, such as, Globaline*, Potable-Aqua*, and others.
These disinfectants can be found in sporting goods stores and pharmacies. Read and follow the manufacturer's instructions. If the water is cloudy then strain it through a clean cloth, and double the number of disinfectant tablets added. If the water is very cold, either warm it or allow increased time for disinfectant to work.
CDC makes no recommendation as to the use of any of the portable filters on the market due to lack of independently verified results of their efficacy.
As a last resort, if no source of safe drinking water is available, tap water that is uncomfortably hot to touch may be safer than cold tap water; however, many disease-causing organisms can survive the usual temperature reached by the hot water in overseas hotels, and boiling or proper disinfection is still advised.
FOOD
Food should be selected with care. Any raw food could be contaminated, particularly in areas of poor sanitation. Foods of particular concern include: salads, uncooked vegetables and fruit, unpasteurized milk and milk products, raw meat, and shellfish. If you peel fruit yourself, it is generally safe. Food that has been cooked and is still hot is generally safe.
For infants less than 6 months of age, breast feed or give powdered commercial formula prepared with boiled water.
Some fish are not guaranteed to be safe even when cooked because of the presence of toxins in their flesh. Tropical reef fish, red snapper, amberjack, grouper, and sea bass can occasionally be toxic at unpredictable times if they are caught on tropical reefs rather than open ocean. The barracuda and puffer fish are often toxic, and should generally not be eaten. Highest risk areas include the islands of the West Indies, and the tropical Pacific and Indian Oceans.
TRAVELER'S DIARRHEA
The typical symptoms of traveler's diarrhea (TD) are diarrhea, nausea, bloating, urgency, and malaise. TD usually lasts from 3 to 7 days. It is rarely life threatening. Areas of high risk include the developing countries of Africa, the Middle East, and Latin America. The risk of infection varies by type of eating establishment the traveler visits - from low risk in private homes, to high risk for food from street vendors. TD is slightly more common in young adults than in older people, with no difference between males and females. TD is usually acquired through ingestion of fecally contaminated food and water.
The best way to prevent TD is by paying meticulous attention to choice of food and beverage. CDC does not recommend use of antibiotics to prevent TD because they can cause additional problems themselves.
Bismuth subsalicylae, taken as an active ingredient of Pepto-Bismol* (2 oz. 4 times daily, or 2 tablets 4 times daily), appears to be effective preventative agent for TD, but is not recommended for prevention of TD for periods of more than three weeks. Side effects include temporary blackening of tongue and stools, occasional nausea and constipation, and rarely, ringing in the ears. Bismuth subsalicylate should be avoided by persons with aspirin-allergy, renal insufficiency, gout, and by those who are taking anticoagulants, probenecid, or methotrexate. It is important for the traveler to consult a physician about the use of bismuth subsalicylate, especially in children, adolescents, and pregnancy.
If you do become ill with traveler's diarrhea, it is usually self-limited and treatment requires only simple replacement of fluids and salts lost in diarrheal stools. This is best achieved by use of an oral rehydration solution such as World Health Organization Oral Rehydration Salts (ORS) solution. ORS packets are available at stores or pharmacies in almost all developing countries. ORS is prepared by adding one packet to boiled or treated water. Packet instructions should be checked carefully to ensure that the salts are added to the correct volume of water. ORS solution should be consumed or discarded within 12 hours if held at room temperature, or 24 hours if held refrigerated.
Iced drinks and noncarbonated bottled fluids made from water of uncertain quality should be avoided. Dairy products can aggravate diarrhea in some people and should be avoided.
Bismuth subsalicylate preparation (1 oz of liquid or 2 262.5 mg tablets every 30 minutes for eight doses) decreases the rate of stooling and shortened the duration of illness in several studies.
Treatment was limited to 48 hours at most, with no more than 8 doses in a 24-hour period. There is concern about taking, without supervision, large amounts of bismuth and salicylate, especially in individuals who may be intolerant to salicylates, who have renal insufficiency, or who takes salicylates for other reasons. Travelers should consult their physicians before using this or any other medications.
Antidiarrheals, such as Lomotil* or Immodium*, can decrease the number of diarrheal stools, but can cause complication for persons with serious infections. These drugs should not be used by anyone with a high fever or blood in their stools.
Antimicrobial drugs such as doxycycline, trimethoprim/sulfamethoxazole (Bactrim™ , Septra™ ), and fluroquinolones (ciprofloxacin and norfloxacin) may shorten the length of illness. Consult your physician for prescriptions and dose schedules.
It is important for the traveler to consult a physician about treatment of diarrhea in children and infants, because some of the drugs mentioned are not recommended for them. The greatest risk for children and especially infants is dehydration. Dehydration is best prevented by use of WHO ORS solution in addition to the infant's usual food. ORS packets are available at stores or pharmacies in almost all developing countries. ORS is prepared by adding one packet to boiled or treated water. The dehydrated child will drink ORS avidly; ORS is given ad lib to the child as long as the dehydration persists. The infant who vomits the ORS will usually keep it down if the ORS is offered by spoon in frequent small sips. Packet instructions should be checked carefully to ensure that the salts are added to the correct volume of water. Breast-fed infants should continue nursing on demand. For bottle-fed infants, full-strength lactose-free, or lactose-reduced formulas should be administered. Older children receiving semi-solid or solid foods should continue to receive their usual diet during diarrhea. Immediate medical attention is required for the infant with diarrhea who develops signs of moderate to severe dehydration, bloody diarrhea, fever in excess of 102° F degrees, or persistent vomiting. While medical attention is being obtained, the infant should be offered ORS.
Most episodes of TD resolve in a few days. As with all diseases it is best to consult a physician rather than attempt self-medication, especially for pregnant women and children. Travelers should seek medical help if diarrhea is severe, bloody, or does not resolve within a few days, or if it is accompanied by fever and chills, or if the traveler is unable to keep fluids intake up and becomes dehydrated.
* The use of tradenames is for identification only and does not imply an endorsement by the Public Health Service or the U.S. Department of Health and Human Services.
CDC Travel Page