Recently there is a growing interest in the airborne spread of virus. In particular, there is growing interest in secondary infection through the air in the hospital. The distribution of air-born virus depends on ventilation system installed in a hospital. In this study, simulations were carried out to predict the move of air-born virus by ventilation system at hospital. Simulation results showed that pressure distribution was –372.05Pa ∼ -3.45 Pa at 1st floor incase of only used mechanical exhaust at bathroom, shower stall , storage, kitchen etc.. if ventilation switch from used mechanical exhaust to mechanical exhaust & mechanical supply. Simulation results showed that pressure distribution was -336.44Pa at stair hall < -0.2Pa at bathroom < mean 1.19Pa at other room. So simulation results showed that using all of the mechanical supply and mechanical exhaust was more effective then the mechanical exhaust for maintain the pressure distribution in hospital. It was also showed that when using the mechanical supply and mechanical exhaust more effectively prevention of air born virus diffusion.

Living organisms are based on the mass flux that induces various biological reactions using nanosized asymmetric ion channels as highly selectivity. However, it is the aggressive challenge to use these channels for artificial membranes because these are fragile and susceptible to deterioration under pH, temperature, mechanical stress, etc. This study, for the first time, synthesized a virus nanochannel-embedded thin film composite membrane. This membrane shows the extremely high ion selectively as well as low resistance. This property can be used to extract various multi-energies, for example, external pressure, water dropping, temperature difference, etc. This electricity results from the entropy gradient between membrane like electric eels.

RNA interference (RNAi) has been considered as an alternative strategy to control agricultural pests whereby double-strandedRNA triggers a potent and specific inhibition of its homologous mRNA. Since small double-stranded RNAs are requiredfor various RNAi applications, there is a need for cost-effective methods for producing large quantities of high-qualitydsRNA. Bacillus thuringiensis produces much insecticidal proteins with expression of their encoding genes being drivenby sporulation-dependent promoters. To develop dsRNA mass-production platform utilizing Bt, the pHT1K-EGFP plasmidvector which has cyt1Aa sporulation-dependent promoter was constructed. The transcriptional level of target gene (EGFP)is higher 113 times than Bt reference gene (ssPE). It was applied to protect honeybee from Sacbrood virus, so targetgene was replaced to SBV-vp1. By ingestion of Bt-derived dsRNA to honeybee shows positive effect on SBV suppression.

West Nile Virus (WNV) is transmitted by infected mosquitoes. Vector mosquitoes usually acquire these pathogens fromfeeding on an infected host, and transmit the pathogens to a naive host during feeding events. To understand the virustransmission dynamics and to survey WNV throughout country, the present study has been conducted. We collected mosquitoesat urban parks in Seongnam, Wonju, Gunsan, Daegu, and Tongyeong using CDC light trap with Dry ice from April toSeptemper in 2017 (mosquito collecting is on going). Among collected mosquitoes, blood-fed mosquitoes were conductedblood meal identification assay and the other mosquitoes were subjected to virus detection using real-time PCR method.A total of 2,290 mosquitoes representing 6 genera and 15 species were collected. The most dominant species was Culexpipiens complex (42.1%) followed by Aedes albopictus (15.1%), Ae. vexans nipponii (14.6%), Ochlerotatus koreicus (9.8%),Cx. orientalis (6.5%), and Armigeres subalbatus (4.4%). The blood meal source were of mammal (93.3%), and birds (6.7%).So far, no WNV has been detected in any mosquitoes.

Vector-borne plant virus transmission is a complex mechanism. Plant viruses modify development and behavior of vectorinsects in a positive, negative, or neutral manner. Bemisia tabaci transmits Tomato yellow leaf curl virus (TYLCV) whichis a virus that seriously damaged tomato cultivars all around the world. We compared several behavioral and physiologicalcharacteristics between non-viruliferous (NV) and TYLCV-viruliferous (V) of whiteflies. When B. tabaci acquired TYLCV,total life span was shorter and fecundity was lower than NV ones. V whiteflies were more susceptible to thermal stressby increasing hsp mRNA levels but higher in mortality by either heat or cold shocks. Further, V whiteflies increasedthe rates of plant sap probing and light attraction behaviors than NV ones. Our results provide insights to understandvector’s role in relation to the acquisition and transmission of plant viruses.

The small brown planthopper (SBPH), Laodelphax striatellus, which transmits rice stripe virus (RSV) is one of thenotorious pests of rice plants. To investigate the factors of vector insect responding to virus introduction, the total RNAof RSV-viruliferous SBPHs was subjected to RNA-Seq to analyze the SBPH-RSV interactome. Based on the transcriptomicchanges of RSV carrying SBPHs, eight cDNA sequences possibly related to RSV replication in SBPH were selected,and dsRNAs targeting those sequences were synthesized and applied to SBPH. Three of those dsRNAs showed over 90%of substantial RSV suppression efficiency in SBPH, that demonstrated a potential of RNAi-based virus-vector managementprogram.

The relationship between virus, vector insect and its host plant has been studied in epidemic of virus disease, fitnessof vector insect, symbiosis and phylogenesis of the relationship, etc. The biological association, symbiosis, concept hasbeen suggested on the virus-vector relationship since 2000. We have conducted such a typical study with the Rice stripevirus and the small brown planthopper, Laodelphax striatellus. In addition, it is able to extend our view to ecosystemservice of the relationship. We reviewed the trophic efficiency included with virus factor. Nutrient loss of the host plantby virus is negative effect but terrestrial decomposition by the virus may be positive feedback in ecosystem. Thus, thevirus-vector relationship is able to be understand not only as competition for the host plant’s nutrition but also as indirectmutualism for the efficient utilization of the host plant or fitness to environmental conditions, especially climate change.

Different types of insect-borne plant viruses can modify their hosts and vectors in distinct manners. Therefore, interactionsbetween two types of viruses co-existing in a field are known to be complex to predict. Obtaining empirical data byconducting field experiments, however, requires numerous biotic and abiotic factors to be controlled, and is therefore hardto execute. Thus, we designed an individual based model to simulate the transmission pattern of two viruses, using potatoes(Solanum tuberosum) for host plant, aphids (Myzus persicae) for virus vector, potato leafroll virus and potato virus Yfor different types of plant viruses. More specifically, we aimed to investigate the effect of the following on the spreadof the plant viruses: dispersal by winged-form aphids, initial number of virus-infected seed potatoes, and indirect interactionsbetween two viruses by affecting life traits of the vectors.

Viral particles of Porcine epidemic diarrhea virus (PEDV) consist of a four structural proteins. Among them Spikeprotein mediated responsible for receptor binding and membrane fusion during viral infection and therefore the main targetof neutralizing antibodies. Virus-like particles (VLPs) are consisted of one or more viral structural proteins, and theirmorphologies closely resemble those of the native virus. VLPs have no virulence and can elicit robust immune responsesas compared with inactivated or live-attenuated virus vaccines. Thus, in this study, we tried two methods for VLP constructionin Bombyx mori, one is traditional method and the other is chimeric VLP method using the influenza matrix protein.Both methods could produce successfully PEDV VLPs.

The hepatitis E virus (HEV) is a leading causative agent of acute hepatitis in humans. Zoonotic HEV strains have been isolated from several animal species, including pigs. New HEV variants have been recently isolated from camels in the Middle East. In the present study, fecal samples from fallow deer, formosan deer, alpaca, and guanaco were analyzed for the detection of HEV. One HEV strain was detected from guanaco, a species of camelids. The nucleotide sequence of guanaco HEV was identical to those of deer HEV-3 strains, which implied the cross-species transmission of HEV-3 from deer to guanaco.

Cherry leaf roll virus(CLRV)는 group IV positive sense ssRNA viruses, Nepovirus로 분류되는 식물병원성 바이러스이다. CLRV는 체리 등 목본 및 완두 등 콩과 작물을 자연 기주로 하며, 실험적으로 약 36개 과 이상의 넓은 기주 범위를 가지고 있어 국가적, 경제적 및 농가 개인적 피해를 야기 할 가능 성이 보고되고 있다. 현재 CLRV를 검출하는 방법으로 역전사(reverse transcription; RT)-nesdted 중 합효소연쇄반응(polymerase chain reaction; PCR) 이 활용되고 있으며, 다양한 기주로부터 CLRV를 검출하기 위해서는 검출 감도, 특이성, 반응 시간, 단순성 등이 중요 요소였다. 그러나 RT-nested PCR은 두 단계로 구성되어 있어 단순하지 않고, CLRV를 검출하는데 약 10시간 이상의 반응 시간이 소 요되었다. 이번 연구에서는 등온증폭법을 이용하여 단순하고 신속하게 CLRV를 검출하는 방법을 개발하 였다. 등온증폭 반응은 RT-nested PCR과 동등한 검출 감도로 CLRV를 검출 하였다. 그러나 반응 시간 을 약 2시간 수준으로 단축하였으며, 6개 영역을 사용하는 등온증폭 프라이머의 사용으로 더욱 특이적 으로 증폭 할 수 있었다.

2010년에 호접란에서 꽃봉오리 낙화를 동반하는 꽃대가 괴 사증상을 나타내는 바이러스로 추정되는 피해가 상업용으로 호접란을 재배하는 경기도 화성지역 농가에서 ‘Fireweak’ 단 일 품종에서 백만주 가량 발생하였다. 난에 발생하는 주요 바 이러스 특이 프라이머를 이용하여 RT-PCR한 결과 ORSV와 CymMV 프라이머 특이 PCR 산물이 증폭되었으며 이 두 개 의 분리주를 각각 ORSV-NIHHSK2와 CymMV-NIHHSK2로 명명하였다. ORSV-NIHHSK2를 ORSV 48개의 국내 분리주 (GenBank accession no. AB541474-AB541521)와 염기서열 상동성을 비교한 결과 98.3~100%이며 아미노산 서열 상동성 은 97.5~100%이었다. CymMV-NIHHSK2를 52개의 CymMV 국내 분리주(GenBank accession no. AB541522-AB541573) 와 염기서열 상동성을 비교한 결과 90.2~100%, 아미노산 서 열 상동성은 96.0~100%이었다. 바이러스에 감염되지 않은 ‘Fireweak’ 품종을 포함하는 6개 계통에 ORSV-NIHHSK2과 CymMV-NIHHSK2 이병즙액을 인공 접종하여 2년 동안 병징 발현을 관찰한 결과 ‘Fireweak’ 품종에서 꽃이 봉오리 상태에 서 노랗게 말라 죽는 증상을 동반하는 꽃대 괴저증상이 접종 주 총 18 그루 가운데 2 그루에서 관찰되었으며, 잎에 황색반 점 및 괴저 증상을 나타내었다. 따라서 ‘Fireweak’ 품종에서 나타내는 꽃대 괴저 증상은 ORSV와 CymMV 단독 또는 복합 감염에 의한 증상임을 보여주었다. 이 결과로부터 호접란 꽃 대 괴저증상은 ORSV 또는 CymMV 감염에 민감한 품종에서 나타나는 것으로 추정되었다. 이 연구는 호접란에서 ORSV 또 는 CymMV 감염에 의한 화기의 괴저 증상에 관한 세계 최초 보고이다.