Anopheles sinensis is an important vector for Plasmodium vivax and thus has been targeted with organophosphates in Republic of Korea. Using the direct contact mortality bioassay, two field populations of An. sinensis from Paju-si and Yeoncheon-gun were characterized for their resistance to organophosphats with RR ratio values (Resistant ratio to imidacloprid) of 446.9 to 756.3 folds and 502.1 to 861.7 folds, respectively. Genomic DNA was used for Allele-specific PCR (AS-PCR) genotyping of the acethylcholine esterase to detect Gly119Ser mutations. The homozygous susceptible Ser/Ser genotype in Paju-si and Yeoncheon-gun was 20.0% and 20.9% and the resistance genotypes were 80.0% and 79.1%, respectively. The homozygous Gly/Ser resistance genotype was the most prevalent as 60.7% in Paju-si and 41.9% in Yeoncheon-gun. Hence, this study suggests that malaria vector control programs should be prepared for the management of organophosphate insecticide resistance.

• Hyunah Kim(Division of Medical Entomology, Center for Immunology and Pathology, NRIH, KCDC)
• Chang-Won Jang(Division of Medical Entomology, Center for Immunology and Pathology, NRIH, KCDC)
• Young-Ran Ju(Division of Medical Entomology, Center for Immunology and Pathology, NRIH, KCDC)
• Kyu-Sik Chang(Division of Medical Entomology, Center for Immunology and Pathology, NRIH, KCDC)