GENOTYPIC DIVERSITY OF DENGUE VIRUS IN AEDES MOSQUITOES COLLECTED FROM DENGUE HOTSPOT AREAS IN KUALA LUMPUR AND SELANGOR, MALAYSIA

Abstract

Dengue fever is endemic in Malaysia and has posed a significant economic and health burden to the country. Malaysia is experiencing the transmission of four dengue serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. To prevent dengue cases, genotypic characterisation is an essential tool to determining the dengue serotypes that are circulating in the dengue cases area. Thus, the objective of this study was to determine the genotype of DENV isolates obtained from DENV-infected Aedes collected. A total of 4,438 Aedes albopictus and 2,454 Aedes aegypti larvae were collected from 132 dengue hotspot localities. They were then reared to adult mosquitoes and pooled. Later, it was tested for determine dengue serotypes using RT-PCR targeting Capsid-preMembrane regions. All DENV serotypes were carefully isolated from DENV positive pools and sequenced. DENV-2, DENV-3, and DENV-4 serotypes were proven positive in 16.83 % of the samples, and were found co-circulating at the study areas. A total 84 isolates were successfully identified, with 17 of them being DENV-2, 36 being DENV-3, and 31 being DENV-4. DENV-2 isolates were of genotype IV, DENV-3 isolates were of genotype III and V, and DENV-4 isolates were of genotype II. This study highlights the importance of active DENV serotype at dengue outbreak areas. This information assists the stakeholders by strengthening dengue genotyping surveillance and providing a solid evidence base for decision making regarding dengue management initiatives. The findings from this study can be utilized to the search for novel genotypes, to the observation of potential genetic alterations in dengue viruses, and to the development of vaccines.