모기는 감염병을 매개하는 종으로 전염병 확산 억제를 위해서는 개체수의 감시와 정확한 예측이 필요하다. 본 연구에서는 모기 개체수 및 기상 및 현장 자료를 활용해 모기 개체수 머신러닝 모델을 개발하였다. 모기 개체수는 디지털 모기 측정기(Digital Mosquito Monitoring System, DMS)의 2015 년~2022년의 5월~10월의 자료를 활용하였다. 기상 자료는 기온, 강수량, 풍속, 습도를 사용하였으며, 현장 조사 자료는 현장을 명목척도와 서열척도로 나누어 기록하여, 명목 척도의 경우 원핫 인코딩으 로 변환해 수치화하여 사용하였다. 분석에 사용된 머신러닝 모델은 Artificial Neural Network, Random Forest, Gradient Boosting Machine, Support Vector Machine이며 성능지표로 R2, RMSE를 사용하였다. 연구 결과, Gradient Boosting 모델이 R2 0.4, RMSE 22.45로 가장 좋은 성능을 나타냈다. 현장 조사 자료 를 분석에 활용하였을 때 R2는 증가하였고, RMSE는 감소하였다. 본 연구 결과 모기 개체수에 현장 조사 자료가 예측 정확도를 향상시킬 수 있음을 확인하였다.

최근 기후변화 및 국제교역량, 여행객, 외국 이주민 등의 증가로 국내 농작물에 큰 피해를 입힐 수 있는 고위험 식물 병의 국내 유입이 꾸준히 증가하고 있고 이에 따라, 검역기관 종사자들의 업무량도 늘어나고 있다. 특히 ‘Candidatus Liberibacter solanacearum’가 원인병원균인 감자 제브라칩병의 경우, 발생하게 되면 감자를 초토화시켜 막대한 피해를 야기한다. ‘Ca. L. solanacearum’의 감자와 토마토 등의 가지과(Solanaceae) 작물과 당근을 포함하는 산형과(Umbelliferae) 작물이 기주가 될 수 있다. 이에 본 연구에서는 아직까지 국내에 유입되지 않은 감자 제브라칩병과 매개충인 토마토 감자 나무이(tomato potato psyllid; TPP; Bactericera cockerelli Sulc.)에 대한 예찰 조사를 수행하였다. 예찰 조사를 위해 전국을 7개 권역(경기-강원, 충청, 전북, 전남, 경북, 경남 및 제주)으로 나누고, 각 권역에 속하는 3개 지역 중심으로 수행하였는데, 경기-강원 권역은 인천, 화성, 춘천 및 홍천, 충청 권역은 공주, 세종 및 청주, 전북 권역은 익산, 완주 및 정읍, 전남 권역은 보성, 고흥 및 순천, 경북 권역은 상주, 김천 및 안동, 경남 권역은 거창, 함양 및 진주, 제주 권역은 구좌 및 성산 지역이 해당되며, 지역당 3개 지점을 두고 조사하였다. 매개충 TPP 조사를 위해 끈끈이 트랩을 이용한 조사를 병행하였다. 예찰 조사는 2018년 9월부터 10월까지 2주 간격으로 실시하였다. 2018년 예찰 조사결과, 감자 제브라칩병과 매개충인 TPP는 국내에는 확인되지 않았다. 이 연구는 식물병을 조기에 탐지하기 위해 구축된 전국적인 모니터링 네트워크를 통해 수행할 수 있었고, 국외 외래유입병들의 예찰 조사를 위한 지역 거점을 확보하는데 기여하였다고 평가된다.

모기는 말라리아, 황열, 뎅기열, 웨스트나일열, 사상충, 치쿤구냐, 일본뇌염, 지카 등의 여러 질병을 매개하고 있고 자연적 요인과 인위적 요인에 의한 지구의 기후변화는 이들 병원성 매개모기들이 점점 더 번성하게 만드는 요인이 되고 있다. 현재 우리나라에서 주목해야 될 감염성 매개질병으로 말라리아와 뎅기열은 기후변화에 의한 기온 상승 요인으로 매개모기의 분포지역 확대와 함께 교통수단의 발달 및 국가 간 빈번한 교류에 의해서 유럽을 비롯한 오세아니아, 동아시아의 온대 지역에서도 감염자의 발생빈도 수가 최근 지속적으로 증가 추세를 보이고 있다. 따라서 기후변화 요인과 인간 활동 등에 의한 요인으로 감염 지역과 매개모기 분포가 미래 예측 불확실성과 복잡성을 가지고 있지만 국내 침입을 막기 위한 해외 유입 방지에 대한 지속적인 모니터링과 방제뿐만 아니라 국가 간 방제 프로그램 공조를 통한 모기에 의해 매개되는 질병 확산에 대비하는 것이 중요할 것으로 생각된다.

Pine wilt disease (PWD) is one of the most important forest tree diseases, especially in the East Asian countries of Japan, China, and Korea. The Japanese pine sawyer, Monochamus alternatus Hope, is the PWN vector for Japanese red pine and Japanese black pine while Monochamus saltuarius Gebler is the vector for Korean white pine. Various control methods, such as aerial pesticide applications, biological control using parasitoids and fumigant such as methyl bromide are used. But the PWD still has spread. Therefore, we were selected effective aerial insecticides. Susceptibility of M. saltuarius and M. alternatus adults were investigated using 9 insecticides which are available in the market in Korea. And then, we tested them to the Apis mellifera to vertify the environmental impact.

There are over 3,000 different species of mosquitoes throughout the world; currently 56 species are reported in Korea. Mosquitoes can act as vectors for many disease-causing viruses and parasites during blood sucking. Various species of mosquitoes are estimated to transmit various types of disease to more than 700 million people annually in Africa, South America, Central America, Mexico, Russia, and much of Asia, with millions of resultant deaths. At least two million people annually die of these diseases, and the morbidity rates are many times higher still. To prevent the spread of diseases, KNIH (Korea National Institute of Health) used three categorized methods; identifying or taxonomic analysis of mosquitoes, detecting virus caring mosquitoes, and detecting malaria from Anopheline mosquitoes. We have proved that taxonomic analysis using DNA barcording method (COI gene) is useful to complement identification of mosquito species. In detecting virus, we have reported Cx. orientalis as a new potential Japanese encephalitis virus (JEV) vector. We also reported that the Anopheline mosquito species composition and Plasmodium vivax infection rates in malaria hot spot in Korea.

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the most important citrus pest, because it serves as a vector of “Candidatus Liberibacter” species that cause huanglongbing disease. Thus, when exporting Rutaceae (citrus), exporting countries put them into quarantine. However, as the size of an imago is so small that only skilled experts can identify it using morphology-based species identification. A PCR-based assay was developed for monitoring psyllids using a rapid, using the DNA extraction from psyllid bodies and PCR amplification. Thus, this study aims to develop a DNA marker system with high species specificity and discrimination power that helps identifying psyllid. We analyzed the base sequence of mitocondria DNA. Based on this sequence, restriction sites were determined and a species particularity primer was made. Several polymorphic regions of mitochondrial DNA of both species were sequenced and used for developing specific restriction sites and polymerase chain reaction (PCR) primers. Also, species-specific PCR primers were devised to develop diagnostic PCR method for identifying the internal feeders. Base sequence results from PCR, which used psyllid species-specific primers, was analyzed by the Mealign program of the CLC Main Workbench analysis software, and used to develop a phylogenic tree. After analyzing this, Hemiptera proved to be allied species.

Oak wilt disease caused by Raffaelea quercus-mongolicae was firstly reported at Sungnam city, Gyeonggi province, Korea, in 2004, and spread to several area of Korean peninsula. Raffaelea quercus-monglicae was transferred by ambrosia beetle, Platypus koryoensis, and caused oak wilt disease. Because oak wilt disease is mediated by ambrosia beetle, Platypus koryoensis, control of this disease concentrates on managing the ambrosia beetle population. Until now, several control methods such as felling and fumigation of dead oak trees with metham sodium, sticky-roll trap for catching emerged or attacking beetles, and oak tree logs for attraction of ambrosia beetle have been mainly used to control oak wilt disease in Korea. Although effective, current control methods have many side effects. Felling of oak tree is very difficult and dangerous to workers. To reduce the side effects of conventional control methods, new and safe types of control method for managing the ambrosia beetle populations are essential. In this study, we investigated the number of caught beetles, effect of height and direction of collection bottles by using newly developed mass capturing device for P. koryoensis to evaluate the effectiveness of this device as practical use in field.

Trombiculid mites are known to be the vector of tsutsugamushi disease by transmitting Orientia tsutsugamushi to human. Although the classification of trombiculid mites is necessary for vector surveillance, their classification by morphological observation is only possible at the larval stage and not easy because of similar shapes as well as tiny body sizes. Further the classification need the specimen production process, it takes much time and the accuracy of classification is changed according to the technology of the researcher. The internal transcribed spacers (ITS) regions of 8 trombiculid mite species were analyzed by amplification using tick common ITS primer sets. We designed molecular marker sets for the identification of five Leptotrombidium species, the lengths of marker L. orientale (1078 bp), L. pallidum (820 bp), L. palpale (1202 bp), L. scutellare (447 bp) and for L. zetum (621 bp) and three Neotrombicula species, the lengths of marker N. gardellai (264 bp), N. japonica (460 bp) and N. kwangneungensis (309 bp) based on alignment of ITS sequences. The markers will be helpful for exact classification of trombiculid mites. This study is the first report on molecular marker of ITS regions of trombiculid mites.

Pine wilt disease, caused by pine wood nematode, Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle, has become the most serious threat to pine trees in Korea since first reported in 1988. Pine wood nematode is transferred to uninfested trees by Monochamus alternatus (Coleoptera: Cerambycidae) (vector). A typical controlling method against vectors in Korea is fumigation of the dead trees infested by vector M.alternatus and B.xylophilus using metam-sodium SL(25%). However, this method is harmful to the environment because of the chemical contamination and vinyl waste in the mountain afterward. Portable Bark Remover (PBR) was contrived to reduce these environmental problems. The vectors oviposite under the bark of the freshly dead trees only. Debark infested trees prohibited the vectors from oviposite and finally, vectors can not complete their life cycle. The PBR is a newly designed as a debarking device that is equipped on top of the chain saw engine allowing ease and rapid debarking of the infested trees at the controlling field. Debarking of freshly-dead trees can eliminate egg-laying and hatch places where between the wood and bark from vectors. The new method for vector controlling using the debarking device is expected to lower-price and high-efficiency comparing with other conventional methods such as “crushing”, “burning” and “fumigation”.

In many cases over the years, we failed to forecast accurately outbreak of Rice stripe virus (RSV) disease using population density of overwintering small brown planthopper (SBPH), Laodelphax striatellus. What is the source of error in this viral disease assessment? For answering the question, spatial distribution of RSV in paddy fields was investigated in relation to the yield of rice grain, and the population density of overwintering SBPH in ridge of paddy fields. Total 14 paddy fields in 5 regions were surveyed in June, 2008. Disease assessment was carried out with each of 30 rice plants in the one of the borders, 5th, 10th line from ridge, and 90 rice plants in diagonal line for conventional method. The ears of rices from 18 plants in the same surveyed line were collected in the late of August for the weights of 100 rice grains. The infection rate of RSV was decreased by the distance from ridge; on the contrary, the increase tendency was shown in the yield of rice grains in the middle of paddy field. It is suggested that the border effect of viral distribution between ridge and paddy field is caused by the spatial distribution of the vector insect. Thus, in this case, the narrow border effect could represent that the SBPH migrated short distance from the ridge to paddy field. The conventional method, observing the disease in middle area of diagonal line, showed no correlation to the population density of overwintering vector generation in ridge. It might cause underestimation of the regional disease rate. The counting of RSV-diseased plant in border line only overestimated it also. However, the RSV infection rate in the near border had highly positive linear relationship (R2=0.91) to the regional average values by regression analysis. Therefore, the near border sampling method can improve the RSV disease risk assessment.

Niemann-Pick type C disease (NPC), known an autosomal recessive disorder, is characterized by abnormal accumulation of cholesterol and glycolipid in late endosome/lysosome. The 95% case in NPC patients are caused by mutation of NPC1 gene, whose gene product is 13 transmembrane-domains and a sterol-sensing domain. The compensation of NPC1 by transgene expression in NPC1-deficient mouse recovered life span and sterility, but neurological correction incompletely, suggesting a possibility of gene therapy. Thus, in order to develop virial expression system for gene therapy of NPC, we isolated NPC1 cDNA and constructed Sindbis viral expression system for verification. NPC1 expression by Sindbis viral expression reduced the accumulation of cholesterol induced by treatment of U18666A and progesterone in both baby hamster kidney (BHK) cells and cultured hippocampal neurons. In addition, NPC1 expression increased the immunoreactivities of post-synaptic density protein 95kDa (PSD-95) in dendrites. On the basis of these results, we constructed a lentiviral vector for NPC1 expression and examined its expression in hippocampal cultured neurons.

Occurrence of the oak wilt disease (Raffaelea sp.) was confirmed in 2004 for the first time in Korea. By using pictorial keys, morphological characteristics of Platypus koryoensis (Murayama), a vector for this disease in Korea, was compared to Platypus quercivorus (Murayama), a vector of oak wilt in Japan. Additionally, suggestions were made for the future research of the vector of oak wilt disease in the northeastern Asia.