Vietnam does not require tourists to have specific vaccinations except for yellow fever, if you come from a country that is hit by the disease. For your health, though, get immunisation from polio, cholera, tetanus, hepatitis A, hepatitis B and typhoid. Be wary against malaria, too. A maximum safety measure would be to secure health insurance. Beware of theft. This can occur during bus stops, when bags on the roof are left unguarded. At rail stations, there are some who grab bags from windows as the train leaves.
Walking along busy cities, such as Ho Chi Minh City, get a good grip on your bag and keep it away from the street. Organized burglars aboard teams of motorcycles can grab your belongings as they speed past. Do not display your mobile phone or expensive jewellery on the street, too. Wear a money belt and leave big amounts of cash at your hotel. Only bring photocopies of your passport unless you need it, such as when transferring locations, renting motorbikes or other purposes.