Passengers arriving in Tanzania should be prepared to show proof of vaccination against COVID-19. As of this writing, travellers entering Tanzania by land must provide proof of vaccination/negative PCR test or take at test at the border. Those entering by air are as of this writing exempt (though this can change so please check the lastest info).
It is highly recommended that you get vaccinated for diseases common in Africa including Yellow Fever and Hepatitis A and B. Full Canadian vaccination recommendations are here (check your own country’s travel advisories for your government’s recommendations).
Further, Tanzania is considered to be “high risk” for malaria, so you should consider taking anti-malarials. Many require you start weeks before travel to Tanzania, so don’t leave to the last minute!