I am going to Fukuoka in southern Japan for a 2-week holiday. Is there an official site that states what vaccinations I should get before my trip?
If you are from Denmark (like OP and I), there is a very handy site called rejsedoktor.dk.
For a two-week trip to Japan, you need the following vaccinations:
- hepatitis A
It is likely that you already have one or more of these vaccinations. Diphteria and tetanus are usually administered together at public school, and lasts for ten years. Hepatitis A lasts for one year, but if you get a follow-up shot within that year, it lasts for 25 years (though my doctor said "for life" – I guess he knows something about my medical conditions that I don't. Hmmm.).
Finally, you can some times find info about this on your country's official travel guides, although they are primarilly for emergencies and security warnings.
There aren't any requirements from most countries. There are recommendations for some. For example: Japanese encephalitis if you're spending lots of time outdoors.
A list for Canadians: http://travel.gc.ca/travelling/publications/well-on-your-way
None. I've lived in Japan for 12 years, never once heard of vaccination requirements nor been asked a single question about it at the airport. I expect it depends on where you are from, but there's nothing here of any particular concern.
(But stay out of the Dengue Fever park in Tokyo.)