Here's Why We've Been Seeing So Much Food-Borne Illness

Summer is supposed to be the best time for fresh produce. Corn on the cob at the cookout. Berries plucked right from the vine. Salads on the cafe patio while you take an extra long lunch break because the weather and the food is that good.

But this year, summer's harvest brought something much different than the flavorful dishes we've come to expect. Since May, the United States has seen more than 17,000 lab-confirmed cyclosporiasis cases. Before this summer's massive outbreak, the country had never recorded more than a few hundred infections in a single year from this parasite, which can cause watery and at times explosive diarrhea.