Role of climate and other factors in determining the dynamics of tick and tick-transmitted pathogen populations and distribution in western, central and eastern Africa.

Naftaly Githaka,Richard Bishop,Esther Kanduma

doi:10.1079/9781789249637.0070

Abstract

Abstract This expert opinion discusses the potential impact of climatic change on vector abundance, survival and transmission of tick-borne pathogens in western, central and eastern Africa. It also discusses the following cases: (1) Rhipicephalus microplus with a focus in West and Central Africa and (2) northern expansion of Rhipicephalus appendiculatus into South Sudan through anthropogenic cattle movement.

Highlights

The African continent ranks highly among regions of the world that are vulnerable to the effects of climate change resulting in shifts in the range and distribution of vector-borne infectious diseases
Climate change has been shown to affect ecological niches and ecosystem parameters in which vectors and their hosts occur at different spatial ranges, influencing survival, adaptation, transmission and disease dynamics
Habitat degradation driven by climate change can reduce habitat quality, resulting in reduction of vector populations and pathogen transmission

Summary

70.1.1 General perspectives

The African continent ranks highly among regions of the world that are vulnerable to the effects of climate change resulting in shifts in the range and distribution of vector-borne infectious diseases. In tropical Africa, the epidemiology of tick-borne diseases is complex, often characterized by co-infestation of animal hosts by multiple tick species and typically resulting in co-infection of livestock and wildlife with multiple tick-borne pathogens. Animal production systems across the continent vary greatly: from intensive small-scale zero-grazing in the cooler highlands, to extensive pastoral systems in the arid and semi-arid rangelands, to hybrid agropastoral systems in areas where ecological parameters, rainfall, are intermediate Such heterogeneity makes it difficult to make generic inferences regarding the potential impact of climate change on vectorborne diseases of livestock. Climate change has been shown to affect ecological niches and ecosystem parameters in which vectors and their hosts occur at different spatial ranges, influencing survival, adaptation, transmission and disease dynamics. It is probable that anthropogenic factors such as poaching, and displacement of wildlife areas through agricultural intensification, may be even more important than climate in modulating wildlife populations

70.1.2 Case study 1

70.2 Future Predictions