Phylogenetic analysis of dengue virus type 3 strains primarily isolated in 2013 from Surabaya, Indonesia

Dengue fever (DF) and its severe form, dengue hemorrhagic fever (DHF), are mosquito-borne viral dis- eases that occur in tropical and subtropical regions. They are caused by 4 serotypes of dengue viruses (DENV) 1–4. Each serotype can be further divided into several genotypes. Epidemiological studies have shown an increased risk of developing DHF after a secondary heterotypic infection, highlighting the urgent need for a better understanding of how the virus spreads as well as its epidemiological trend.In Indonesia, more than 100,000 cases of DF/DHF have been annually reported in recent years. Phylogenetic analysis revealed that particular types of DENV that spread throughout the region had their origin in Indonesia. Although the country is considered to be an important dengue-endemic area, sequence information available for the circulating dengue virus strains is limited. Furthermore, the largest number of Japanese dengue cases was found in Indonesia during 2006–2010. Therefore, conducting dengue research in Indonesia is of paramount importance.