Nothing can wreck a vacation like getting sick, especially in another country.
Some countries require proof of vaccination to enter.
Check with a physician who specializes in travel medicine, or the Centers for Disease Control and Prevention. The flu can be deadly for those who are over 65 or have chronic diseases. At least the flu is a bug we know. But as we travel to more exotic places for both vacation and business, Americans may encounter less-familiar microbial threats, says New York travel physician Bradley Connor of the International Society of Travel Medicine. Among them is malaria, a risk in more than 100 countries.