maxbiostat
commented
9 years ago Again, main problem with the data.
Closed maxbiostat closed 9 years ago
maxbiostat
commented
9 years ago Again, main problem with the data.
The “Spatio-temporal dynamics of FMDV in South America” study by Carvalho et al. describes the historical spatio-temporal dispersal of FMDV across the South America continent reconstructed using phylogeography analyses employed through a Bayesian spatial diffusion model. The reported results define transmission networks and transmission hubs (at country level) that would explain the historical spread of FMD within the continent. In addition, the authors deal with variables likely associated with the FMD spread (i.e. geographical distance, livestock density, and livestock trade) in trying to explain their causative effect associated with historical FMD outbreaks. As last attempt, the authors correlated the demographic dynamics of FMDV with reported number of FMD outbreak and vaccination coverage in trying to assess the impact of FMD control policies on the FMDV diversity and its population expansion/contraction through time. Although the methodological approach has been previously used in different setting and the results would be interesting for a computational basis, there are several aspects of the study that need to be carefully considered before the paper would be suitable for publication. In fact, the presence of bias in the data used is potentially producing an incorrect picture of FMD in South America. In addition, although the authors are examining the potential impact of the sampling bias in the sequence data analysed, this is only properly discussed as Supplementary Text and not in the main paper, where they assume the results as correct, valid and without bias. One major problem of the study is the data. They claim to have analysed all the data publicly available in GenBank but (as detailed below) this is not correct and the analyses should be repeated including the full sequence dataset. I would be, therefore, really cautious to draw important conclusion from this study given the issues reported, which might hold true only for the time-frame pictured from the data you have analysed. As already said, this study need a proper revision before being published and this main revision would involve the re-analysis of all the data adding all the sequences available in GenBank and which are not included in this version.