Pine wilt disease caused by Bursaphelechus xylophilus has continued to expanding in Korea since its first occurrence identified from Busan in 1988. The direction of spread and density of two vector insects, Monochamus saltuarius and M. alternatus, are closely associated with the expansion and occurrence of pine wilt disease being observed in Korea. In 2016, a pheromone trap was installed to investigate the density of each vector. A correlation between the density of two insect vectors and the number of trees infected by pine wilt disease was further investigated in Gyeongnam, Gyeongbuk, Ulsan, and Jeju. To perform a correlation analysis, the number of infected trees was counted within a radius of 50m from which the pheromone traps were installed. In addition, factors that might have an effect on the density of vectors were investigated. This includes the altitude, temperature and forest type from the site where the pheromone traps were installed.
Beetles of the genus Monochamus Dejean (Coleoptera: Cerambycidae) are the most important vectors of the pine woodnematode (PWN), Bursaphelenchus xylophilus (Steiner & Buhrer) (Nematoda: Aphelenchoididae). The most efficient wayto control pine wilt disease is to decrease the population levels of the vector Monochamus beetles. Specific and efficientnatural enemies would be an interesting and environmental-friendly option. From 2016 to 2017, we investigated on thelarval parasitoids associated with M. alternatus Hope and M. saltuarius Gebler using the sentinel logs (Pinus koraiensis)in South Korea. As results of this work, we report two larval ectoparasitoids, Spathius verustus Chao and Cyanopterusflavator (Fabricius) (Hymenoptera: Braconidae) from six survey sites. Each parasitoid was parasitized up to 58.2% and26.3% on 1st and 2nd instar larvae of Monochamus beetles, respectively. These parasitoids are likely to be highly efficientas bio-control agents. Morphological characters with illustration and some biological information of them are provided.
As climate change and the increase of international trade, the possibility of infectious disease inflow is increasing into Republic of Korea (ROK). Nine of total 16 cases overseas travel related Zika virus disease and 140 of 314 cases in dengue fever occurred during mosquito season throughout ROK in 2016, which increase importance on the studies of disease vectors for effective control and monitoring. However, the vector resources for the studies are not enough to support the studies by private research institutes and universities. Korea Center for Disease Control and Prevention (KCDC) has secured and maintained the disease vectors, comprised of 5 genus and 15 species in an insectarium system. KCDC has supported the disease vector resources through the system wherever to request them. In this presentation, the insectarium systems will be introduced.
Climate change by global warming is predicted to affect on public health including increasing incidence of vector borne diseases. Vector borne diseases are transmitted by arthropod vectors, such as mosquitoes, chigger mites and ticks, and are highly sensitive to climate changes. The surveillance and R&D of infectious disease vectors are becoming important for climate change preparedness in Korea. So far, 10 regional vector surveillance centers (Incheon, Gyeonggi, Gangwon, Chungbuk, Chungnam, Jeonbuk, Jeonnam, Gyeongbuk, Gyeongnam, and Jeju) have been established to monitor vectors and their pathogens against endemic diseases (japanese encephalitis, malaria, scrub typhus and SFTS) and imported diseases (dengue fever, west nile fever and yellow fever). The information on geographical distribution as well as real-time monitoring of vectors and their pathogens will be presented by this surveillance system, ‘VectorNet’. The R&D plan on vectors and their pathogens is now discussing in government-wide R&D committee on infectious diseases. The R&D areas will be included: 1) establishment of nationwide monitoring system, 2) study on biological and molecular characteristics, 3) development of vector identification and pathogen diagnosis methods, 4) development of vector control techniques, 5) management and conservation of vector resources.