Evolutionary history of Dengue virus type 4: Insights into genotype phylodynamics

Dengue virus type 4 (DENV-4) circulates in tropical and subtropical countries from Asia and the Americas. Despite the importance of dengue virus distribution, little is known about the worldwide viral spread. Following a Bayesian phylogenetic approach we inferred the evolutionary history of 310 isolates sampled from 37 countries during the time period 1956–2008 and the spreading dynamics for genotypes I and II. The region (tropical rainforest biome) comprised by Malaysia–Thailand was the most likely ancestral area from which the serotype has originated and spread. Interestingly, cross-correlation analysis on demographic time series with the Asian sequences showed a statistically significant negative correlation that could be suggestive of competition among genotypes within the same serotype.

► We inferred the evolutionary history of 310 DENV4 worldwide isolates.
► The serotype likely originated and spread from the area Malaysia–Thailand.
► Spreading dynamics for genotypes I and II was elucidated.
► Negative correlation on demographic time series suggest intra-serotype competition.