INTERNATIONAL INDIGESTION (TURISTA)   Most of us are traveling again this summer with the pandemic in our rearview mirror. And faraway lands are once more popular destinations.  Along with international travel comes the real chance of developing traveler’s diarrhea.  When I was younger and more carefree in where and what I ate, I developed turista several times in developing countries: in Egypt where I ate a falafel from a street vendor; in Mexico where I drank an iced cocktail; and in India where I ate at a restaurant our guide had told us to avoid. But, even without foolish moves such...