Profile of Theme

The emergence of infectious diseases is of particular interest at present, with high-profile diseases such as Ebola and MERS Coronavirus causing widespread public concern alongside the potential for societal disruption. Whilst the term ‘emerging’ is commonly used to describe newly evolved or previously undetected diseases, it may also apply to pathogens that are increasing their geographic spread and impact, or moving into human hosts for the first time. The relationship between humans and animals plays an important role in disease emergence; it is estimated that 60 – 80% of newly emerging infections are zoonotic in origin (capable of transmission from animals to humans). Disease emergence is not a new phenomenon, and the changes in disease dynamics that lead to an emergence ‘event’ represent a natural evolutionary response by the pathogen to constantly changing conditions. However, evolutionary pressures brought about by human-induced (anthropogenic) changes on the environment such as urbanisation, are projected to increase the frequency of pathogen emergence in the future.

 Urbanisation is predicted to increase most rapidly in developing countries, with huge population increases projected for urban centres in Africa. Without adequate urban planning, fast rates of urban growth are likely to have knock-on effects for healthcare, sanitation and food production, that may affect the dynamics of disease transmission in these areas. Through our research, we aim to investigate the role that varying degrees of urbanisation play in the emergence of new human or livestock pathogens.