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Background Bovine tuberculosis (bTB) by Mycobacterium bovis (M. bovis) is endemic in cattle in Latin America, and even though government programs exist for the control and eradication of the disease, efforts are hindered by the limited resources available for farmer compensation and program operation. Epidemiological surveillance and strain characterization are key for understanding disease dynamics, for which whole genome sequencing (WGS) is a powerful tool. Currently, there is limited information regarding bTB in the Caribbean, so the aim of this study was to use WGS to characterize M. bovis strains circulating in the Dominican Republic (DR). Results A total of 81 M. bovis isolates were obtained from cattle from different regions were sequenced and analyzed. Phylogenetic and ancestral reconstruction/temporal analyses were performed to investigate M. bovis genetic diversity, population structure, and potential dates of introduction into the Dominican Republic. Three main lineages were identified: DR1, DR2 (consisting of subgroups DR2a, DR2b, and DR2c), and DR3. Cluster analysis revealed at least four introductions of M. bovis during the 19th century and the first half of the 20th century. The most recent common ancestors to the DR lineages were linked to the United States, Mexico, Argentina, and Brazil, from where historical imports of cattle have occurred. Population structure analyses indicated that M. bovis is largely panmictic in the Dominican Republic, with no relationship between geographic location and genotype. Conclusion The current study provides important information regarding the origin of M. bovis strains circulating in the Dominican Republic, its genetic diversity and spread in the local cattle herds, providing a frame of reference for continuing M. bovis surveillance. Finally, this study significantly contributes to the worldwide M. bovis framework.

Vector-borne diseases are a major public health problem. Amongst them, dengue, Zika and chikungunya illnesses are increasing their incidence and geographical expansion. Since vector control is the main measure to prevent these diseases, this systematic review aims to determine the effectiveness of environmental interventions for the prevention of the transmission of these three diseases, as well as for the reduction of their burden. Experimental studies of environmental management interventions aimed at vector control were included. The outcome variables of interest were disease burden indicators and entomological indicators. Of the 923 references initially retrieved, after discarding those that were duplicated or didn't comply with the inclusion criteria, a total of 7 articles were included. All included studies carried out environmental manipulation interventions and only 1 carried out an environmental modification intervention. Regarding the outcome variables, all used entomological indicators (larval or pupae indices). Of those, pupae indices are better indicators of vector abundance. In 4 out of the 6 studies, there was a statistically significant reduction of the pupae indices related to the elimination of small containers, manipulation of large tanks and cleaning outdoor spaces. These interventions are easy to implement and involve little resources, which acquires special importance regarding areas with limited resources. Although it is assumed that a reduction of mosquitoes would lead to a reduction or the risk of transmission, a little evidence proving this has been published. It would be advisable that, in addition to entomological indicators, epidemiological, environmental and sociodemographic factors would be taken into consideration, bearing in mind that mosquito density is one of the many factors that influence the transmission of these viruses. None of the papers included used disease indicators, not allowing to demonstrate if environmental interventions contribute to reduce disease burden.

The New World screwworm, Cochliomyia hominivorax (Coquerel 1858) (Diptera: Calliphoridae), is a serious parasite of livestock, humans, and other warm-blooded animals. It has been eradicated from the northern parts of its historical range down to the Panama—Colombian border where a permanent barrier zone is maintained. This eradication was accomplished through using the sterile insect technique (SIT). In 2016 there was an outbreak of C. hominivorax in the Florida Keys. In only six months, this pest was successfully re-eradicated using SIT, but the geographic origin of the invasion has yet to be resolved. It was previously determined that the Florida flies most likely represented a single invasion, and it was recommended that a finer-scale genetic assessment should be completed. Thus, this current proof-of-concept study aimed to develop a population genetic database using single nucleotide polymorphisms (SNPs) to reference outbreaks and potentially identify the origin of the Florida outbreak. This initial database consists of wild-caught samples from 4 geographic locations as well as laboratory colony samples that originated from 7 additional locations using a genotyping by sequencing (GBS) approach. Geographic population structuring was identified for twelve populations that clustered according to geographic location. The Florida outbreak samples appeared similar to samples from the outer Caribbean cluster which included samples from Dominican Republic and Trinidad and Tobago, however, these results will be further clarified with the replacement of laboratory colony samples with future wild-caught samples.