Tourists could soon have a new accessory to add to travel-sized toothpaste tubes and electrical adapters: an anti-diarrhea patch. A new US study shows that travelers wearing a “transcutaneous immunization” patch, loaded with E. coli toxins, reliably protected wearers against diarrhea and vomiting, the BBC reports. Those who did get sick bounced back much more quickly than a control group. (More diarrhea stories.)