Laboratory and semi-field evaluation on OmniPrene™ G against Aedes, Anopheles and Culex mosquitoes

Abstract

With the current existing, emerging, and resurging mosquito species and mosquito-borne diseases, and very low availability of mosquito control products, exploration of novel active ingredients and innovative formulations based on available active ingredients are crucial to ensure the sustainable mosquito control interventions. The larviciding by applying biorational mosquito larvicides with microbial and insect growth regulator origins is a routine practice in most areas. The current paper evaluated an innovated granular S-methoprene formulation, namely OmniPrene™ in the laboratory bioassays, as well as outdoor microcosms at 2.8, 5.6 and 11.2 kg/ha with 30.5 cm water depth, and at 2.8 kg/ha with shallow water (15.25 cm) against Aedes aegypti, Anopheles hermsi and Culex quinquefasciatus. Over 90% efficacy was achieved against Aedes and Anopheles for at least 49 days, and against Culex for up to 42 days at 2.8, 5.6 and 11.2 kg/ha when water depth was 30.5 cm. The control levels were further elevated when water depth was 15.25 cm, where over 90% control was observed for 63 days against Aedes and Anopheles, but 56 days against Culex. The high initial and residual efficacy were attributable to the unique diatomaceous earth carrier granules and proprietary binding process. With well documented bioactivity and safety of S-methoprene, demonstrated performance of the OmniPrene G, plus the unique feature of the formulation to render vegetation penetration, even coverage, and other advantages of dry granules, it would be reasonable to recommend this product as one of the routine larvicidal tools in a wide variety of habitats against mosquito species of public health importance while complying with the local regulations.