Emerging zoonotic diseases have assumed increasing fundamental importance in both public and animal health, as the last few years have seen a steady increase of new cases, each emerging from an unsuspected geographic area and causing serious problems, often leading to mortalities among animals and humans. The reasons for disease emergence or re-emergence are multiple and include certain major factors, such as expansion of the human population, climate change and globalisation of trade. Further contributing issues, such as the increased movement of animal species, microbial evolution, ecological disruption, changes in human behaviour, all imply that emerging diseases will not only continue to occur, but the rate of their emergence will also increase. These will constitute constraints for the attainment of the Millennium Development Goals by African Governments by 2015. There is no doubt that the current trend calls for more and stronger partnerships between national and international organisations, veterinary and medical communities, environmentalists, academics and policy-makers of various governments on the continent within the context of the global 'One Health' movement. This article attempts to analyse the impact of emerging diseases and the implications for the achievement of the Millennium Development Goals in Africa by the year 2015.