Modelling the impact of climate change on the distribution and abundance of tsetse in Northern Zimbabwe

Parasites & Vectors

Cyril Caminade¹  Jennifer S. Lord²  Steve Torr²  Joshua Longbottom³  Harry S. Gibson⁴  Daniel J. Weiss⁴ 

[1] Department of Livestock and One Health, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK;Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK;Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK;Centre for Health Informatics, Computing and Statistics, Lancaster Medical School, Lancaster University, Lancaster, UK;Malaria Atlas Project, Big Data Institute, University of Oxford, Oxford, UK;

关键词: Tsetse;    Northern zimbabwe;    Spatial model;    Abundance estimates;    Sleeping sickness;    r-HAT;   

DOI  :  10.1186/s13071-020-04398-3

来源: Springer

【 摘 要 】

BackgroundClimate change is predicted to impact the transmission dynamics of vector-borne diseases. Tsetse flies (Glossina) transmit species of Trypanosoma that cause human and animal African trypanosomiasis. A previous modelling study showed that temperature increases between 1990 and 2017 can explain the observed decline in abundance of tsetse at a single site in the Mana Pools National Park of Zimbabwe. Here, we apply a mechanistic model of tsetse population dynamics to predict how increases in temperature may have changed the distribution and relative abundance of Glossina pallidipes across northern Zimbabwe.MethodsLocal weather station temperature measurements were previously used to fit the mechanistic model to longitudinal G. pallidipes catch data. To extend the use of the model, we converted MODIS land surface temperature to air temperature, compared the converted temperatures with available weather station data to confirm they aligned, and then re-fitted the mechanistic model using G. pallidipes catch data and air temperature estimates. We projected this fitted model across northern Zimbabwe, using simulations at a 1 km × 1 km spatial resolution, between 2000 to 2016.ResultsWe produced estimates of relative changes in G. pallidipes mortality, larviposition, emergence rates and abundance, for northern Zimbabwe. Our model predicts decreasing tsetse populations within low elevation areas in response to increasing temperature trends during 2000–2016. Conversely, we show that high elevation areas (> 1000 m above sea level), previously considered too cold to sustain tsetse, may now be climatically suitable.ConclusionsTo our knowledge, the results of this research represent the first regional-scale assessment of temperature related tsetse population dynamics, and the first high spatial-resolution estimates of this metric for northern Zimbabwe. Our results suggest that tsetse abundance may have declined across much of the Zambezi Valley in response to changing climatic conditions during the study period. Future research including empirical studies is planned to improve model accuracy and validate predictions for other field sites in Zimbabwe.

【 授权许可】

CC BY