Phlebotomine sand flies have long been incriminated as vectors of leishmaniasis in various parts of both the Old and New World. Prompted by recent indigenous cases of leishmaniasis in Thailand, a bionomic study of sand flies was undertaken in Tham Phra Phothisat temple, Saraburi province. In this study, sand flies were collected using Centers for Disease Control (CDC) light traps, to clarify the activity patterns and species composition of the sand flies. Traps were laid from August 2005 to July 2006. The insects were collected monthly between 1800-0600 hours. A total of 8,131 sand flies were collected with a female:male ratio of 1.9:1. Sixteen species were identified, of which 5 belonged to the genus Phlebotomus, 9 to Sergentomyia and 1 to Chinius. Species comprised the abundant species (Sergentomyia silvatica 35.6%, Sergentomyia barraudi 18.1%, Sergentomyia anodontis, 17.1%, Sergentomyia iyengari 11.9%, and Sergentomyia gemmea 11.2%); the less common species (<2%) were Sergentomyia dentata 1.8%, Phlebotomus stantoni 1.1%, Sergentomyia indica 1.0%, Phlebotomus argentipes 0.8%, Sergentomyia perturbans 0.4%, Chinius barbazani 0.3%, Phlebotomus asperulus 0.2%, Phlebotomus philippinensis gouldi 0.1%, Phlebotomus major major 0.1%, Sergentomyia quatei 0.1% and Sergentomyia bailyi 0.1%. The results revealed seasonal variation in sand fly prevalence, with the highest peak in July. Soil samples collected were characterized by alkaline (pH 7.6).

Plants contain numerous bioactive compounds that can be used to develop environmentally-safe insect control agents. Castor oil is a vegetable oil derived from the seeds of castor bean and is widely used as an industrial lubricant and medicinal purgative. In search of an alternative natural insecticide, the objective of this study was to evaluate the larvicidal and adulticidal activities of castor oil against the important dengue vector, Ae. aegypti. Larvicidal and adulticidal bioassays were conducted following the World Health Organization methods. Larvicidal activity was observed at castor oil concentrations of 10, 25, 50, 75, and 100 ppm; larval mortality was checked after 48 h of exposure and the lethal concentration (LC) at LC50 and LC90 were 51.38 and 116.26 ppm, respectively. Adulticidal activity was determined by topical application at the concentrations of 1, 5, 10, 15, and 20 µg/ mg on female mosquitoes and the mortality was checked after 24 h of exposure. The effective adulticidal activity was apparent with the LD50 and LD90 values of 6.03 and 25.07 µg/mg against female mosquitoes. The results indicated that castor oil has potential in the practical control of both immature and adult stages of the mosquito vector.