sparse prior to 2000. Recent Malaysian MoH data from the Sentinel Surveillance System provide a more robust information source and 2012 data showed a heterogeneous distribution of the DENV serotypes in the separate state [12]. It can be speculated that changes in predominant circulating serotypes may have implications for the incidence and severity of dengue disease, as major outbreaks tend to follow the switching of DENV serotypes in the population [7]. The relationship between infection with DENV serotypes and the occurrence of different forms of the disease is multi-factorial and not fully understood. However, high dengue disease endemicity and the co-circulation of multiple DENV serotypes indicate that a high proportion of the population is at risk of severe dengue disease.