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Bronsvoort, M.

Publications and source records attributed to Bronsvoort, M..

3 recordsLinked to original sources

Importance of wildlife in the circulation and maintenance of SAT1 and SAT2 foot-and-mouth disease viruses in Africa

Author summaryFoot and mouth disease (FMD) viruses are endemic in sub-Saharan Africa. Due to the complexity of the disease epidemiology and the lack of available data, there is a need to use phylogenetic approaches to understand the role of potential hosts involved in the circulation and maintenance of the viruses. The uneven host sampling of the available sequences requires us to take advantage of the recent advances in phylogenetic reconstruction. Therefore, using two structural coalescent model approximations we estimated the circulation of FMD virus serotypes SAT1 and SAT2 between cattle, buffalo and impala populations. Our results suggest that in Africa, the impala population seems to act as an intermediate host between the cattle and buffalo populations and play a more important role in the circulation of the viruses than was previously suspected. Until now, the role of the impala population in the circulation of FMDV has been suggested, but never explicitly shown.

molecular biology↗

The evolution and phylodynamics of serotype A and SAT2 foot-and-mouth disease viruses in endemic regions of Africa

Foot-and-mouth disease (FMD) is a major livestock disease with direct clinical impacts as well as indirect trade implications. Control through vaccination and stamping-out has successfully reduced or eradicated the disease from Europe and large parts of South America. However, sub-Saharan Africa remains endemically affected with 5/7 serotypes currently known to be circulating across the continent. This has significant implications both locally for livestock production and poverty reduction but also globally as it represents a major reservoir of viruses, which could spark new epidemics in disease free countries or vaccination zones. This paper describes the phylodynamics of serotypes A and SAT2 in Africa including recent isolates from Cameroon in Central Africa. We estimated the most recent common ancestor for serotype A was an East African virus from the 1930s compared to SAT2 which has a much older common ancestor from the early 1700s. Detailed analysis of the different clades shows clearly that different clades are evolving and diffusing across the landscape at different rates with both serotypes having a particularly recent clade that is evolving and spreading more rapidly than other clades within their serotype. However, the lack of detailed sequence data available for Africa seriously limits our understanding of FMD epidemiology across the continent. A comprehensive view of the evolutionary history and dynamics of FMD viruses is essential to understand many basic epidemiological aspects of FMD in Africa such as the scale of persistence and the role of wildlife and thus the opportunities and scale at which vaccination and other controls could be applied. Finally we ask endemic countries to join the OIE/FAO supported regional networks and take advantage of new cheap technologies being rolled out to collect isolates and submit them to the World Reference Laboratory.

epidemiology↗

Circulation of Foot-and-Mouth Disease Virus in Africa and identification of the underlying constraints using Phylogeographic methods

Foot and mouth disease (FMD) is endemic in sub-Saharan Africa and can lead to important and continuous economic losses for affected countries. Due to the complexity of the disease epidemiology and the lack of data there is a need to use inferential computational approaches to fill the gaps in our understanding of the circulation of FMD virus on this continent. Using a phylogeographic approach we reconstructed the circulation of FMD virus serotypes A, O and SAT2 in Africa and evaluated the influence of potential environmental and anthropological predictors of virus diffusion. Our results show that over the last hundred year the continental circulation of the tree serotypes was mainly driven by livestock trade. Whilst our analyses show that the serotypes A and O were introduced in Africa trough livestock trades, the SAT2 serotype probably originates from African wildlife population. The circulation of serotype O in eastern Africa is impacted by both indirect transmission through persistence in the environment and anthropological activities such as cattle movements.

evolutionary biology↗