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arXiv · 1603.04773

Malaria elimination campaigns in the Lake Kariba region of Zambia: a spatial dynamical model

Milen Nikolov·Caitlin A. Bever·Alexander Upfill-Brown·Busiku Hamainza·John M. Miller·Philip A. Eckhoff·Edward A. Wenger·Jaline Gerardin
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Abstract

Background As more regions approach malaria elimination, understanding how different interventions interact to reduce transmission becomes critical. The Lake Kariba area of Southern Province, Zambia, is part of a multi-country elimination effort and presents a particular challenge as it is an interconnected region of variable transmission intensities. Methods In 2012-13, six rounds of mass-screen-and-treat drug campaigns were carried out in the Lake Kariba region. A spatial dynamical model of malaria transmission in the Lake Kariba area, with transmission and climate modeled at the village scale, was calibrated to the 2012-13 prevalence survey data, with case management rates, insecticide-treated net usage, and drug campaign coverage informed by surveillance. The model was used to simulate the effect of various interventions implemented in 2014-22 on reducing regional transmission, achieving elimination by 2022, and maintaining elimination through 2028. Findings The model captured the spatio-temporal trends of decline and rebound in malaria prevalence in 2012-13 at the village scale. Simulations predicted that elimination required repeated mass drug administrations coupled with simultaneous increase in net usage. Drug campaigns targeted only at high-burden areas were as successful as campaigns covering the entire region. Interpretation Elimination in the Lake Kariba region is possible through coordinating mass drug campaigns with high-coverage vector control. Targeting regional hotspots is a viable alternative to global campaigns when human migration within an interconnected area is responsible for maintaining transmission in low-burden areas.

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Milen Nikolov, Caitlin A. Bever, Alexander Upfill-Brown, Busiku Hamainza, John M. Miller, Philip A. Eckhoff, Edward A. Wenger, Jaline Gerardin. 2016-03-15. Malaria elimination campaigns in the Lake Kariba region of Zambia: a spatial dynamical model. https://doi.org/10.1371/journal.pcbi.1005192

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