Traveling, Safe Water and Diarrhea

Contaminated food and drink are the major sources of stomach or intestinal illness while traveling. Intestinal problems due to poor sanitation are found in far greater numbers outside the United States and other industrialized nations.

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. In areas 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, and 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. 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. Centers for Disease Control and Prevention 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, water that is uncomfortably hot to touch may be safe for drinking and brushing teeth after it is allowed to cool. However, many disease-causing organisms can survive the usual temperature reached by the hot water in overseas hotels.

What about 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. Infants younger than 6 months should either be breast-fed or be given 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, amber jack, grouper, and sea bass can occasionally be toxic at unpredictable times if they are caught on tropical reefs rather than in 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.