When you visit Davos, whether it be during the winter or during the off season, you do not have to worry about your health or safety. In the winter there are many more visitors than in the other seasons. This is a pretty popular ski resort location, and people come from all over Europe to ski here. Even with all of these tourists coming into the town, there is a low rate of crime and hardly and disturbances. The police force in town takes notes of problems and takes care of them very quickly and efficiently. There aren't any diseases or health related problems in the town either. The only thing you might have to watch out for is a runny nose from being out on the slopes all day. If you visit in the off season, there will be considerably less people around in the town. Even though there are less people, you are still as safe as you would be at the height of the season. People working in restaurants or hotels still treat you very well. You should always have your passport on you just in case. If you get into any problems let the police force know, or contact the United States Embassy if it's very important.