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Owing to global climate change, the global resurgence of vector‐borne infectious diseases and their potential to inflict widespread casualties among human populations has emerged as a pivotal burden on public health systems. In this study, the prevalence of flaviviral diseases transmitted by mosquitoes, and their target vector diversity, abundance, and distribution was investigated to enable the mapping of hotspots for these diseases. For the surveillance of the vector mosquitoes carrying flaviviruses during April to November 2015, female mosquitoes were collected to study whether they carried pathogens from abroad at seven locations in Incheon Metropolitan City (Incheon) as a typical urban area and Hwaseong‐si (= city, Hwaseong) of Gyeonggi‐do (= province) as a rural area. A total of 15 species belonging to seven genera (29,102 female mosquitoes) were collected with black‐light and BG‐Sentinel™ traps at a collection rate of 260 per trap/night from whole collection locations. The most collected mosquito species in Incheon were Aedes vexans nipponii (species ratio (SR), 29.9%) and the Culex pipiens complex (SR, 28.8%), followed by Anopheles sinensis s.l. (SR, 27.9%) and Ochlerotatus koreicus (SR, 7.1%). From the results of viral RNA detection, five flaviviruses were found in 20,981 individuals (excluding An. sinensis; 696 pools) in the Cx. pipiens complex and Ae. vexans nipponii. Three Japanese encephalitis virus (JEV)‐positive pools were from the Cx. pipiens complex, a Chaoyang virus pool was found from Ae. vexans nipponii, and the remaining unidentified flavivirus pool was from Cx. pipiens. The three JEV‐positive pools were phylogenetically grouped as genotype V. The results of our study demonstrate that enhanced monitoring and long‐term surveillance of these vector viruses are of great public health importance.

The seasonal abundance of hard ticks that transmit severe fever with thrombocytopenia syndrome virus was monitored with a collection trap method every April to November during 2015-2018 and with a flagging method every July and August during 2015-2018 in Ganghwa-do (island) of Incheon Metropolitan City, Republic of Korea. This monitoring was performed in a copse, a short grass field, coniferous forest and broad-leaved forest. A total of 17,457 ticks (8,277 larvae, 4,137 nymphs, 3,389 females, and 1,654 males) of the ixodid ticks comprising 3 species (Haemaphysalis longicornis, H. flava, and Ixodes nipponensis) were collected with collection traps. Of the identified ticks, H. longicornis was the most frequently collected ticks (except larval ticks) (94.26%, 8,653/9,180 ticks (nymphs and adults)), followed by H. flava (5.71%, 524/9,180) and Ix. nipponensis (less than 0.04%, 3/9,180). The ticks collected with collecting traps were pooled and assayed for the presence of SFTS virus with negative results. In addition, for monitoring the prevalence of hard ticks, a total of 7,461 ticks (5,529 larvae, 1,272 nymphs, 469 females, and 191 males) of the ixodid ticks comprising 3 species (H. longicornis, H. flava, and Ix. nipponensis) were collected with flagging method. H. longicornis was the highest collected ticks (except larval ticks) (99.53%, 1,908/1,917 ticks (nymphs and adults)), followed by H. flava (1.15%, 22/1,917).

Owing to climate change, the global resurgence of vector‐borne infectious diseases has emerged as a critical public health issue. Orientia tsutsugamushi is the etiological agent of tsutsugamushi disease (scrub typhus) a mite‐borne acute febrile disease occurring in the Asia‐Pacific region. We investigated the prevalence of tsutsugamushi disease transmitted by chigger mite vectors living on rodents. Using sticky‐type chigger traps for three months during 2016–2018, 1,057 chigger mites were collected (chigger mite index, 1.31) from four locations in the Hwaseong‐si area of Gyeonggi‐do, Republic of Korea. Five species distributed among three genera were identified. In addition, 94 rodents were captured (collection rate: 7.83%) using Sherman live traps over the course of three months (April, October, and November) during 2016–2017. Three rodent species were captured and identified and the striped field mouse (Apodemus agrarius) was the dominant rodent host species in the surveyed area. A total of 10,469 ectoparasitic chigger mites were recovered from the 94 rodents, from which 13 species distributed among four genera were identified. Of the 5,250 chigger mites examined, Leptotrombidium pallidum was most abundant (n = 2,558), followed by L. orientale, L. scutellare, L. zetum, Euschoengastia koreaensis, L. subintermedium, and Neotrombicula tamiyai. Of the examined chigger mites, no groups recovered from rodent hosts tested positive for O. tsutsugamushi. This study provides fundamental regional information on vector‐borne disease data collection in the Hwaseong‐si area, Gyeonggi‐do, and will further contribute to formulating disease control and prevention strategies.

Owing to global climate change, the global resurgence of vector-borne infectious diseases and their potential to inflict widespread casualties among human populations has emerged as a pivotal burden on public health systems. Tsutsugamushi disease (scrub typhus) in the Republic of Korea is steadily increasing and was designated as a legal communicable disease in 1994. The disease is a mite-borne acute febrile disease most commonly contracted from October to December. In this study, we tried to determine the prevalence of tsutsugamushi disease transmitted by chigger mites living on rodents and investigated their target vector diversity, abundance, and distribution to enable the mapping of hotspots for this disease in 2015. A total of 5 species belonging to 4 genera (109 mites): Leptotrombidium scutellare 60.6%, L. pallidum 28.4% Neotrombicula tamiyai 9.2%, Euschoengastia koreaensis/0.9%), and Neoschoengastia asakawa 0.9% were collected using chigger mite collecting traps mimicking human skin odor and sticky chigger traps from April to November 2015. Chigger mites causing tsutsugamushi disease in wild rodents were also collected in Hwaseong for the zoonotic surveillance of the vector. A total of 77 rodents belonging to 3 genera: Apodemus agrarius (93.5%), Crocidura lasiura (5.2%), and Micromys minutus (1.3%) were collected in April, October, and November 2015. The most common mite was L. pallidum (46.9%), followed by L. scutellare (18.6%), and L. orientale (18.0%). However, any of the chigger mite pools collected from rodent hosts was tested positive for Orientia tsutsugamushi, the pathogen of tsutsugamushi disease, in this survey.

Flaviviruses, for example, dengue virus (DENV) and Zika virus (ZIKV), and Alphaviruses, for example, chikungunya virus (CHIKV), attracted little attention until 2000 when increasingly higher numbers of infections were reported in urban settings throughout much of the tropical and subtropical areas of the world. While Aedes aegypti is the primary vector in most areas, Aedes albopictus, which is present in relatively high numbers in forested areas of the Republic of Korea (ROK), as well as limited urban environments (e.g., where used tires are improperly stored), is considered a secondary vector. Aedes albopictus gained considerable attention in 2016 when > 100 imported cases of DENV were reported annually since 2010 in the ROK as travelers returned home from endemic countries,1 in addition to 16 imported cases of ZIKV in 2016. ZIKV, a member of the Family Flaviviridae, was first isolated in Uganda, Africa, from monkeys in 1947 and from Aedes africanus in 1948.2 While there were occasional cases and outbreaks, its recent adaptation to efficiently infect Ae. aegypti, Ae. albopictus, and several other Aedes spp. in the Pacific Islands has led to its widespread dispersal and outbreaks in many of the tropical and semitropical regions of the world, including nine countries in Asia, 47 in Central and South America, one in North America, 10 in Oceania, and two in Africa, with the potential to spread to temperate regions during “mosquito seasons”.3–6 ZIKV is a monkey-mosquito-monkey forest cycle zoonotic disease that has been adapted to an urban Ae. aegypti-man-Ae. aegypti (and related Aedes species) cycle with the potential for emergence in nonendemic areas where competent mosquito vectors (e.g., Ae. albopictus) are present.7 Worldwide, Ae. aegypti, and Ae. albopictus to a lesser degree because of its broader range of hosts, have been identified as primary and secondary vectors of ZIKV.8 Vector competence studies of Ae. albopictus and Ae. aegypti exposed to the same mice infected by ZIKV showed that the viremia levels in mice produced disseminated infections. However, Ae. albopictus infection rates were more dose dependent, requiring higher blood meal titers than titers required for Ae. aegypti infections.9 Unfortunately, as with other arboviruses, for example, West Nile virus and CHIKV, there are no government approved human vaccines or other specific treatments for ZIKV.10 Therefore, it is essential to implement effective vector control for target species near residences where imported ZIKV-infected patients in the ROK are identified to decrease the potential human-vector-human transmission risks during the late spring to fall mosquito season. An example of this type of approach occurred in Chiba City, Japan, in 2014, when emergency vector surveillance and control strategies of Ae. albopictus were implemented due to local transmission of DENV. The result was that Ae. albopictus populations were significantly reduced after adult control strategies were implemented, which also reduced the risks for future transmission of DENV.11 A total of 16 imported ZIKV cases, including one asymptomatic case, were identified from January to October 2016 in the ROK. Nine of the cases were reported during the primary mosquito season from June to October.12 All ZIKV cases were attributed to transmission by mosquitoes during their travels to foreign ZIKV endemic countries, with 77% of the cases attributed to travel to Southeast Asia (Philippines, Vietnam, and Thailand).13 While the Korean Centers for Disease Control & Prevention (KCDC) has established vector control guidelines for vivax malaria and Japanese encephalitis that are endemic in the ROK, there were no established guidelines for vector control of nonendemic vector-borne diseases, for example, ZIKV, DENV, and CHIKV, imported from tropical and subtropical countries where they are endemic. To reduce the potential for autochthonous transmission of imported mosquito-borne viruses during the mosquito season in the ROK, the KCDC established guidelines in 2016 for the control of Ae. albopictus, the primary vector in Korea.4 However, the efficacies of these guidelines have not been fully evaluated.

Pumping in ejectors is a measure of how much the secondary fluid is entrained by the high momentum primary flow and is one of the crucial performance indices. In the fuel recirculation system of fuel cells, the entrained secondary fluid contains water vapor due to the over-supplied hydrogen, making the secondary fluid humid. In such cases, the relative humidity of the secondary fluid alters the fluid properties of the mixed flow. This study examines such effects of relative humidity on ejector. A new analytical model has been developed, and series of measurements has been conducted to validate the model’s prediction. The present results demonstrate that higher relative humidity of the secondary fluid reduces pumping in an ejector. During the mixing process of the two fluids, condensation releases heat, increasing the ejector operating temperature. Thus, secondary flow density is decreased, and pumping is lowered.

Echinostoma cinetorchis is an oriental intestinal fluke causing significant pathological damage to the small intestine. The aim of this study was to determine a full-length cDNA sequence of E. cinetorchis endoribonuclease (RNase H; EcRNH) and to elucidate its molecular biological characters. EcRNH consisted of 308 amino acids and showed low similarity to endoribonucleases of other parasites (

Japanese encephalitis virus (JEV) is a single stranded positive sense RNA virus of the genus Flavivirus that belongs to family Flaviviridae and emerged as one of the most pivotal form of viral encephalitis. The virus is transmitted to humans by mosquito vector and is an etiological agent of acute zoonotic infection. In this study, we investigated distribution and density over 3-year period in central regions of Korean peninsula. We selected two cities as mosquito-collecting locations and subdivided them into five collection sites; downtown Incheon Metropolitan City as a typical urban area, and the Hwaseong-si area as a rural area. A total of 35,445 female culicine mosquitoes were collected using black light traps or BG Sentinel™ traps from March to November 2016-2018. Aedes (Ae.) vexans nipponii was the most frequently collected specimens (48.91%), followed by Culex (Cx.) pipiens (32.05%), Ochlerotatus (Och.) dorsalis (13.58%), Och. koreicus (1.68%), and Cx. tritaeniorhynchus (1.49%). In the urban area, Cx. pipiens was the predominant species (92.21%) and the other species accounted for

A survey of aflatoxin B 1 and ochratoxin A was conducted on dried red pepper and red pepper pow-der. Total number of 193 samples were collected from local markets in Incheon. The presence of aflatoxin B 1 and och-ratoxin A was determined by high performance liquid chromatography (HPLC) with fluorescence detector usingimmunoaffinity column clean-up. The recovery rate of aflatoxin B 1 and ochratoxin A were more than 80% and thelimits of quantification were 0.13µg/kg for aflatoxin B 1 and 0.30µg/kg for ochratoxin A. Aflatoxin B 1 was detectedin 33 samples (17.1%) with a range of 0.14~9.67 µg/kg and ochratoxin A was detected in 40 samples (20.7%) with arange of 0.31~3.31 µg/kg. These results show that the occurrence of aflatoxin B 1 and ochratoxin A in dried red pepperand red pepper powder tested in this study is low compared with the standard in Korea Food Code (10µg/kg as afla-toxin B 1 and 7 µg/kg as ochratoxin A).Key words : aflatoxin B 1 , ochratoxin A, dried red pepper, red pepper powder