Detection and serotyping of dengue viruses in aedes aegypti and aedes albopictus (Diptera: Culicidae) collected in Surabaya, Indonesia from 2008 to 2015

Aedes aegypti and Aedes albopictus are the primary and secondary vectors, respectively, of dengue, the most important arboviral disease in the world. The aim of this study was to detect and serotype dengue viruses (DENV) in the vectors Ae. aegypti and Ae. albopictus in Surabaya, Indonesia. Between 2008 and 2015, 16,605 Aedes mosquitoes were collected in 15 sub-districts of Surabaya. Ae. aegypti was dominant (90.9%), whereas few Ae. albopictus were collected (9.1%). A total of 330 pools of adult Aedes mosquitoes were subjected to the serotyping of DENV by RT-PCR. DENV-1 (52.3%) was the most frequently detected serotype, followed by DENV-2 (40.3%), DENV-4 (4.6%), and DENV-3 (2.8%). The average minimum infection rate for Ae. aegypti in various sub-districts of Surabaya was 7.2 per 1,000 mosquitoes, while that for Ae. albopictus was 0.7 per 1,000 mosquitoes. The results showed that the predominantly circulating DENV serotype in mosquitoes continuously shifted from DENV-2 (2008) to DENV-1 (2009-2012), to DENV-2 again (2013-2014), and then back to DENV-1 (2015). The circulating DENV serotypes in mosquitoes were generally consistent with those in humans. Therefore, the surveillance of infected mosquitoes with DENV might provide an early warning sign for the risk of future dengue outbreaks.