Salje H, Wesolowski A, Brown TS, et al. Reconstructing unseen transmission events to infer dengue dynamics from viral sequences. Nature Communications. 2021;12(1):1810.
Researchers hypothesize that their development of a phylogenetic, spatiotemporal framework overcomes the inadequacy of phylogeographic approaches as their framework considers the roles of factors which a phylogeographic approach is unable to. These factors include vector presence, age of individuals at risk, local immunity, and movement of infected and susceptible individuals.
The developed framework was applied to dengue in seven different Thai provinces using 726 geocoded viral sequences collected from 1995-2012. Of the factors analyzed (age of individuals at risk, vector presence, local immunity, and movement of infected and susceptible individuals), application of the researchers’ proposed framework found that age-dependent mixing of individuals and vector distributions (i.e., probability of Aedes aegypti presence) are not important factors in determining dengue spread.
Researchers hypothesize that the removal of the effect of assortative mixing by the intermediary vector may be driving their finding that there is no evidence of age-dependent transmission. Moreover, researchers hypothesize that the lack of linkage between vector presence and transmission may be driven by limited heterogeneity in estimated presence across Bangkok.
Existence of homotypic serotype immunity is correlated with decreased transmission whereas the existence of heterotypic serotype immunity indicates a higher likelihood of transmission. Finally, results indicate infected individuals are less mobile than susceptible individuals with the latter being mainly children. https://doi.org/10.1038/s41467-021-21888-9