In general, persons planning to visit developing countries should consult a physician before departure. A list of Travel Clinics is available from the International Society for Travel Medicine (
www.istm.org/) or the American Society for Tropical Medicine and Hygiene
(www.astmh.org/). Most travelers should contact their physician at least six weeks prior to travel. Adventure travelers, those who plan prolonged stays, and those who will leave the usual tourist routes should contact their physician six months prior to travel. Advice may also be obtained from the Centers for Disease Control and Prevention (
www.cdc.gov/travel/) or the World Health Organization (
www.who.int/ith).