Suddenly you feel terribly sick, your stomach is cramping, you run to the bathroom every two minutes with severe diarrhea. Keep something with you? Do not even think! A gastrointestinal flu, everyone will confirm, is hell. And also terribly persistent. The gastrointestinal flu is triggered by so-called Noroviruses , pathogens that are transmitted orally-fecally. Even small (and with the naked eye unrecognizable) amounts of stool residues or vomit on food, objects or hands are sufficient for an infection. Especially nasty: This starts from one to the other minute. There is no real protection against noroviruses. Constant disinfection, that might help. But disinfectants are sometimes of health concern – and you do not even have them on hand quickly. Lemon juice destroys noroviruses A substitute for chemically produced ingredients comes from nature – and is found in most kitchens. As scientists of the research group Noroviren of the CHS Foundation at the German Cancer Research Center and the University of Heidelberg have discovered, lemons are just as effective as disinfectants as all artificially produced products. The citric acid kills the noroviruses and prevents infection with the pathogen. Grant Hasman, head of the study, said: "Our research indicates that the juice of just one lemon is enough to prevent infection." Now it is quite handy to know that the lemons are suitable for disinfection – but really exciting is the next result of the scientists. They want to find out whether the juice of citrus fruits is also suitable for the direct treatment of gastrointestinal influenza. And we? Do not wait for the research. But drink our lemon water just preventively … (here you will find the timetable for intestinal rehabilitation).