Is the water safe?
A traveler getting ready to go to Southeast Asia for the first time asked me for the number one piece of advice I would have for a traveler in that area. What I told him is applicable to most of the world: "Don't drink the water."
Water and water-related illnesses are the most commonly contracted by travelers in these areas. They are prevalent, and the last thing you want is a bout of diarrhea just before you step on that six hour bus ride to Yogyakarta or Ayutthaya. Part of the reason that water-related illnesses are so common is there as so many possible avenues of exposure. The list below is to help you think possible situations in which it is possible to contract water-born illnesses and strategies to avoid or solve such situations.
The stuff that comes out of the tap should be treated as poison. Think about it as some deadly soap. You can use to to wash your body off (usually), but you never want to ingest it. That means you don't use it to rinse out your mouth, clean your toothpaste, and you certainly do not drink it. Keep a bottle of filtered water in your bathroom to have for brushing your teeth and rinsing your brush.
(2) Bathroom Wash Water:
(3) Water in Your Food:
Most locals cannot drink their tap water, either, but still risk exposure by brushing their teeth with tap water, washing food in it, and using it in everyday life. If you have long-term exposure to a particular area you may loosen up on your tapwater exposure, but expect to get sick--possibly very sick--as you move towards greater immunity.
In the meantime, you have to be aware of how locals are using water around you. Fresh vegetables are often washed with water which, as you know, may remain on it when it is served to you. Raw vegetables are better prepared and eaten only by yourself; eating them outside is risking exposure to a water-born disease. Also remember that most food you encounter that calls for water (rice, soup, et cetera) has likely been made using tapwater. That is fine as long as it has been boiled, and generally tea and coffee will almost always be fine. Just be sure to always avoid cold food and watch out for buffets--while the water-born illnesses may have been taken care of, cold food can cause food poisoning.
The boiling point of water drops by approximately 1 degree Fahrenheit for every 550' of elevation gain above sea level. One of the worst illnesses of my life came from forgetting this rule while trekking in the highlands of Sumatra; not considering the considerable gain in altitude, I boiled my water a few minutes for tea. However, at about 7000 feet (2134 meters) the boiling point of water is less that 200' Fahrenheit. I should have added at least five additional minutes for the gain in altitude in order to ensure that all the microorganisms in the water were killed. The spent the next four days in a rural village being nursed by locals who were themselves without ready access to medical care.
The lesson learned was to know how long to boil water. So how long do you need to boil water to sterilize it? You should safely figure three minutes at a full boil plus one minute for each thousand feet above sea level. Usually, you don't need to worry about this, however, unless you are going above 2,000 feet above sea level (about 600 m).
(5) Freshwater Swimming:
We all love to swim, and there are many inviting lakes, rivers and water falls throughout Southeast Asia. While beautiful and appealing, they are also potentially dangerous (and not just because of the man-eating Borneo crocodiles, either!). Parasitic infections are acquired by eating or drinking contaminated food or water, through direct contact with soil or water containing parasites or their larva, or by contact with biting insects. Several types of parasites can penetrate intact skin and travelers are advised to wear shoes and avoid swimming, wading, or washing in fresh water. Of these, Schistosomiasis [shis-to-so-MY-uh-sis] is perhaps the most serious, a disease of the tropics that can lead to serious, long-term illness. It occurs in the Philippines, Laos, Cambodia, central Indonesia, and the Mekong Delta area. People get schistosomiasis by contact with fresh water containing flatworm eggs. In rare cases, eggs can travel to the brain or spinal cord and cause seizures, paralysis, or spinal cord inflammation. What to take away from all this? Be careful about swimming in fresh water, consider whether it may be polluted, and also think about seeing a doctor on your return for a parasite check which usually includes a blood and stool sample.
Your chances of getting a parasite far outweigh your
chances of encountering a croc
The Ice Question:
Ice is overwhelmingly safe in Southeast Asia since most of it is commercially produced using filtered water. In places like Cambodia, where many lack refrigerators, people depend on purchased ice to keep things cold in coolers. Throughout tourist areas, knowledge that filtered ice is essential is already well known. When in rural areas or "off the beaten track," ice may be more a concern and bottled and hot drinks are probably best. Thoughout Malaysia, Thailand, Bali and developed tourist spots, you don't have to worry about the ice in kopi ais or Ais Kacang.
A few simple water-related precautions can help ensure your days in Southeast Asia are spent exploring rather than moaning in the toilet, or worst, spending a few days in a foreign hospital or having an unpleasant reminder of your trip six months later when you begin showing signs of a parasitic infection. Remember thousands of people visit Southeast Asia each year without so much as a sniffle--as they say, prevention is the best medicine.