No inoculations are mandatory, but it's worth discussing the following with your doctor: cholera, diphtheria, tetanus, hepatitis A, hepatitis B, polio, tuberculosis, typhoid
While most food and drink is considered safe, there is a small risk of parasitic infection or ingesting toxins from raw seafood. Typhus(an acute infectious fever) is known to occur in some river valleys. Japanese encephalitis also poses a threat. Health insurance is recommended.
Despite its densely urbanised population Japan is one of the safest countries in the world. The likelihood of encountering any crime is slim, that is unless you are a bicycle owner, where theft can almost be guaranteed. Much more serious is the threat posed by earthquakes.Japan 's four large islands are home to approximately 10% of the world's active volcanoes and the setting for a similar percentage of the world's major earthquakes. The also have some of the world's most advanced warning systems. In the event of an earthquake the consensus on advice is as follows: Don't leave your building(as falling masonry is one of the biggest dangers), but take shelter away from the windows under the most solid thing you can find. Once the quake has passed head for the nearest park, open space or neighbourhood emergency centre.