Several vaccinations are recommended to protect international travellers, especially to tropical countries, from diseases in other parts of the world. Firstly, the routine schedule of childhood vaccinations and booster shots according to the Swiss immunisation programme should be checked, updated or even completed. Additional vaccinations against hepatitis A and B, typhoid fever, poliomyelitis, rabies or Japanese encephalitis may be recommended. This will depend on a number of factors including the exact destination and route (developing countries, rural areas), planned activities (backpacker, family visit, business trip), duration of travel, season, age of the traveller and current health status including the current medication and previous vaccinations. Some vaccinations, such as yellow fever, may be required for travellers to certain countries and the international certificate of vaccination may even be required when entering a country from another country where yellow fever is endemic. The international certificate of vaccination (or a letter of exemption when appropriate) is considered valid only if it is administered by an approved vaccination centre. Furthermore, the meningococcal vaccination (A, C, W, Y) is required for pilgrims to Saudi Arabia. It is recommended to start the vaccinations four to six weeks before departure to ensure enough time to administer all the necessary doses for an adequate immune response. All commonly used vaccines can be administered on the same day. The basic health insurance does not usually cover travel vaccines.