Use purified water for brushing your teeth as well as drinking
Safe water to drink is boiled, purified, or bottled
Reliable purification systems include both a filter (for killing parasites) and a chemical (for killing viruses & bacteria) such as chlorine dioxide.
Drink carbonated drinks, hot tea or coffee
Avoid ice in your drinks
Be cautious of unpasteurized dairy, ice cream, street vendors, buffet food, raw vegetables such as salads, large reef fish (grouper, snapper, barracuda) even if cooked.