In sub-Saharan Africa (SSA), natural increase in the population, rural-urban migration and internal displacement account for unprecedented rates of urbanisation, with much of the growth taking place in large cities. Nowadays, the majority of urban residents live in crowded informal housing often built on inadequate land (floodplains, marshy areas, dumpsites…), with inadequate water supply, sanitation and waste disposal, which poses serious health threats. Moreover, the urban characteristics vary widely between cities and within the same city where formal and informal settlements coexist, resulting in spatial patterns of socioeconomic inequalities. This rapid rate of urban growth and the associated demographic, environmental and socioeconomic changes modify the epidemiology of vector-borne diseases, and more specifically of malaria.
According to the World Health Organization (WHO), it is estimated that 90% of all malaria deaths worldwide occur in Africa. Malaria has been considered a predominantly rural disease in Africa and malaria intervention across the continent remains focussed on rural, highly endemic communities with far fewer strategic policy directions for the control of malaria in fast growing cities. Yet, urban malaria in sub-Saharan Africa is a major health problem that is likely to become increasingly important, unless addressed. The heterogeneity of intra-urban malaria risk is not captured in continental risk-mapping initiatives. Better identifying the pockets of focal transmission within urban areas would be extremely useful for policy makers as it would help to better target interventions within urban areas where the high population densities make a large population at risk. Moreover, the inter-urban risk variations have never been taken into account in malaria risk modelling.
REACT addresses these societal issues through its two main goals:
- Improving our knowledge of intra-urban malaria risk. We know that the risk is lower in urban areas compared to rural areas, but we also know that the risk of malaria infection does persist within densely populated urban settings of Africa. The project aims to better understand the various factors responsible for focal malaria transmission in urban African settings. There is a definite need to expand research into the unique epidemiology of malaria transmission in urban areas for focal elimination and sustained control agendas at the city-level.
- Improving our knowledge of inter-urban malaria risk. The risk of malaria transmission varies considerably between cities. African cities are very heterogeneous in terms of size, population density, rate of urban growth, environmental changes occurring in the peri-urban areas, etc. The project aims to improve the predictability of malaria risk in African cities by better understanding factors responsible for these variations.