No vaccinations are currently required for entry into Tanzania when arrival is directly from North America or Europe.
Yellow Fever: It is mandatory for all visitors to mainland Tanzania and Zanzibar to have a valid Yellow Fever Certificate if they are coming from an endemic country, this includes Kenya and Uganda and it must be administered at least ten days before your arrival (or re-entry) into Tanzania. If your travel itinerary requires you to have a yellow fever vaccination, you must ask your doctor to provide you with an "International Certificate of Vaccination," which should be carried with you while travelling to serve as proof that you have fulfilled the vaccination requirement. If proof of vaccination is required and you do not carry it with you, you may be denied entry into Tanzania.
Malaria: Anti-malarial medication is recommended for all travellers to Tanzania. Your doctor will prescribe the best choice based on your own health history and your specific destination(s) in Africa.
Personal protection measures should be taken to avoid mosquito bites, especially (but not limited to) the hours between dusk and dawn when malarial mosquitos are most active. These measures include using an insect repellent containing at least 20% to 35% of the active ingredient "DEET;" keeping your arms and legs covered as much as possible; and avoiding the use of perfume, hairspray, and other scented products that attract mosquitos.