Agriculture is a very important sector in this country, being the 2nd largest contributor to the GDP (30%) and by far the largest employer, employing over 70% of the active population. Tanzania has the 2nd largest number of animals on the African continent after Ethiopia, in terms of the number of cattle, sheep, goats and chickens. In addition to breeding, the large number of national parks (17 animal reserves) and the continuation of lifestyles closely linked to the life cycle of the livestock, especially in the Masai Territory, means there is a very high rate of human-animal interaction in this country. Morogoro, the centre of the AfyaData programme, is thus the entry point for Mikumi National Park, much frequented by tourists looking to see the Big Five, but is also the national reference centre for monitoring the problems of “One Health”, which links human health with animal health.