Spatio-temporal Dynamics of Foot-and-Mouth Disease Virus in South America

Luiz Max Carvalho; Nuno Rodrigues Faria; Andres M. Perez; Marc A. Suchard; Philippe Lemey; Waldemir de Castro Silveira; Andrew Rambaut; Guy Baele

arXiv · 1505.01105

Spatio-temporal Dynamics of Foot-and-Mouth Disease Virus in South America

Luiz Max Carvalho·Nuno Rodrigues Faria·Andres M. Perez·Marc A. Suchard·Philippe Lemey·Waldemir de Castro Silveira·Andrew Rambaut·Guy Baele

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Abstract

Although foot-and-mouth disease virus (FMDV) incidence has decreased in South America over the last years, the pathogen still circulates in the region and the risk of re-emergence in previously FMDV-free areas is a veterinary public health concern. In this paper we merge environmental, epidemiological and genetic data to reconstruct spatiotemporal patterns and determinants of FMDV serotypes A and O dispersal in South America. Our dating analysis suggests that serotype A emerged in South America around 1930, while serotype O emerged around 1990. The rate of evolution for serotype A was significantly higher compared to serotype O. Phylogeographic inference identified two well-connected sub networks of viral flow, one including Venezuela, Colombia and Ecuador; another including Brazil, Uruguay and Argentina. The spread of serotype A was best described by geographic distances, while trade of live cattle was the predictor that best explained serotype O spread. Our findings show that the two serotypes have different underlying evolutionary and spatial dynamics and may pose different threats to control programmes. Key-words: Phylogeography, foot-and-mouth disease virus, South America, animal trade.

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Luiz Max Carvalho, Nuno Rodrigues Faria, Andres M. Perez, Marc A. Suchard, Philippe Lemey, Waldemir de Castro Silveira, Andrew Rambaut, Guy Baele. 2015-06-01. Spatio-temporal Dynamics of Foot-and-Mouth Disease Virus in South America. https://arxiv.org/abs/1505.01105

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