This study aimed to investigate the effectiveness of ultraviolet (UV) insect light traps for mosquito control and to study the relationship between this effect and weather factors in coastal areas of Samut Songkhram province, Thailand. The study sites were divided into two areas, approximately 2and 4 km from the sea. The trap was placed less than one meter away from the house, where it could reach electrical plugs. The effectiveness of UV light trap was tested from September to October 2017 between 6: 00 p.m. and 6: 00 a.m., for a total of 30 days. A total of 2,605 adult mosquitoes within four species belonging to two genera were collected, including Anopheles epiroticus Linton & Harbach, Culex quinquefasciatus Say, Cx. sitiens Wiedmann and Cx. gelidus Theobald. The effectiveness of UV insect light traps in area 2 km from the sea trapped 45.96 ± 42.13 mosquitoes per night and area 4 km from the sea trapped 40.83 ± 33.61 mosquitoes per night. While, effectiveness comparison of the UV insect light traps 2 and 4 km from the sea of were shown to be statistically significantly different (p < 0.05). These results of this study are useful for planning and application of UV light traps to control mosquito populations in coastal areas of Samut Songkhram province, Thailand and other coastal areas.

Aedes aegypti, also called the dengue or yellow fever mosquito, is a significant vector species of several viruses especially the dengue virus. Reducing Ae. aegypti population can directly reduce dengue outbreaks in the community. The research aim is to assess the efficacy of commercial botanical pure essential oils of garlic (Allium sativum) and anise (Pimpinella anisum) against Ae. aegypti larvae, the mortality of larvae was monitored after 24-and 48-h of exposure. The larvicidal activity of garlic oil after 24-h exposure was 0.005 ppm for LC 25 , 0.006 ppm for LC 50 , and 0.012 ppm for LC 90 , and after 48 h exposure was 0.004 ppm for LC 25 , 0.006 ppm for LC 50 , and 0.014 ppm for LC 90. Meanwhile, the larvicidal activity of anise oil after 24-h exposure was 0.016 ppm for LC 25 , 0.023 ppm for LC 50, and 0.043 ppm for LC 90 , and after 48-h exposure was 0.014 ppm for LC 25 , 0.020 ppm for LC 50 , and 0.037 ppm for LC 90 , whereas, Aedes larval mortalities increased with an increase in the concentration of garlic and anise essential oils after both 24-and 48-h exposure. The results of this study were clear evidence for the efficiency of commercial plant oil for dengue vector larval control, especially garlic essential oils.