Malaria is transmitted by female mosquitoes in the genus Anopheles and is a major public health issue. Different species of Anopheles mosquitoes have different epidemiological characteristics, behaviors, and ecological requirements, and so an understanding of their biology and ecology in a particular area is critical for successful disease control. The aim of this study was to determine which environmental factors are associated with Anopheles larvae in a malaria-endemic area in Ratchaburi Province, Thailand, which shares a border with Myanmar. In October 2016, we collected mosquito larvae and measured six environmental factors at 10 study sites located along Lam Pachi River, which flows through Huay Nam Nak village in Ratchaburi Province. We found two species of Anopheles larvae (An. subpictus sensu lato (s.l.) Grassi and An. barbirostris s.l. van der Wulp) at 7 of the 10 study sites, the numbers of which significantly differed between sites (p < 0.05). Pearson correlation analysis showed that the numbers of larvae of both species were significantly positively correlated with the dissolved oxygen level (p < 0.01) and significantly negatively correlated with the width of the river (p < 0.05) and pH (p < 0.01). By contrast, turbidity, water depth, and water temperature were not associated with larval abundance. Mosquito species which belong to genus Anopheles are considered to be of public health and medical importance. Therefore, Anopheles mosquito surveillance and control in the study sites are essential. This information will facilitate vector-borne disease control and improve our understanding of the biology of Anopheles vectors in rivers located along international borders, further reducing the number of patients in this malaria-endemic area.

Chaiphongpachara T, Laojun S, Kunphichayadecha C. 2018. Effect of the CDC light trap on control of nocturnal mosquitoesin coastal Samut Songkhram Province, Thailand. Biodiversitas 19: 1750-1754. This study aimed to investigate the effect of CDC lighttrap on mosquito control and to study the relationship between this effect and weather factors in coastal areas (2 and 4 km from the sea)of Samut Songkhram Province, Thailand. We conducted a field test by trapping for 30 consecutive days from September to October2017. The trap was hung at a height of 1.5 m and was 50 m away from a house. A total of 2963 adult female mosquitoes of 4 speciesbelonging to 2 genera were trapped, including Anopheles epiroticus Linton & Harbach, Culex quinquefasciatus Say, Cx. sitiensWiedmann and Cx. gelidus Theobald. The trapping rate of the CDC light trap set up 2 km from the sea was 85.70±73.81 adultmosquitoes per night. Meanwhile, at the location 4 km from the sea, the trap collected 13.07±11.40 adult mosquitoes per night.Comparing the numbers of mosquitoes captured by the CDC light trap between these two sites, there was a significant difference at p <0.05. This study shows that the CDC light trap can be used for effective control of mosquitoes in coastal areas of Samut SongkhramProvince, Thailand, especially Cx. sitiens, a filariasis vector.

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.

Objective: The aim of this research is to study the effectiveness of mosquito magnet (MM) for reducing mosquitoes (Diptera) populations in coastal areas. Materials and methods: The study sites are in the coastal area of Samut Songkhram province, Thailand, which is divided into two locations; one that is 2 km and another that is 4 km in distance from the sea. We used the Mosquito Magnet ® Independence (MMI) trap for effective field testing in Samut Songkhram Province, Thailand. Traps were placed 100 m away from the house (one trap per location) and mosquitoes were collected at night from 6 PM to 6 AM during September and October 2017 (30 days). Results: A total of 2,561 adult mosquitoes, including Anopheles epiroticus Linton & Harbach , Culex quinquefasciatus Say , Cx. sitiens Wiedmann, and Cx. gelidus Theobald were collected by MMI. At a 2-km distance from the sea were captured more mosquitoes per night more than at a 4-km distance (63.63 ± 42.30 vs. 21.70 ± 12.42). The comparison of effectiveness of MMI in two locations of the coastal area was shown to have a statistically significant difference ( p < 0.05) and analysis of the correlation between the number of mosquitoes caught in coastal areas, including at a 2- and 4-km distance from the sea, accounting for weather factors, we found that the effectiveness of MMI was not correlated with weather ( p > 0.05). Conclusion: Overall, this study demonstrated that MM can be used to control mosquitoes in coastal areas with high efficiency, especially 2 km away from the sea.