The Korea Disease Control and Prevention Agency has established centers at 16 locations to screen vector populations and pathogens. The aims of this study were to determine the relative spatiotemporal distributions of mosquitoes that are flavivirus vectors, and to correlate them with instances of flaviviral disease in the Republic of Korea (ROK). We collected 67,203 mosquitoes in traps at 36 collection sites in 30 urban regions and migratory bird habitats in 2020.
View Article and Find Full Text PDFThe occurrence of tick-borne infectious diseases, including zoonotic babesiosis, has become a serious concern in recent years. In this study, we detected Babesia spp. using polymerase chain reaction (PCR) amplification of the 18S rRNA of the parasites isolated from ixodid ticks collected from small mammals in the Republic of Korea (ROK).
View Article and Find Full Text PDFThe Korea Disease Control and Prevention Agency has established regional centers at 16 locations to monitor vectors and pathogens. We investigated the geographical and temporal distribution of chigger mite populations to understand tsutsugamushi disease epidemiology in 2020. To monitor weekly chigger mite populations, 3637 chigger mites were collected from sticky chigger mite traps in autumn.
View Article and Find Full Text PDFThe seasonal distribution of hard ticks was investigated in 2018 in Gyeongbuk Province, Republic of Korea. Ticks were assayed for severe fever with thrombocytopenia syndrome virus (SFTSV). Ticks were collected monthly using CO-baited traps from April to November in four habitats (grasslands, grave sites, hiking trails, and mixed forests).
View Article and Find Full Text PDFOwing 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.
View Article and Find Full Text PDFThis study aimed to determine the presence of SARS-CoV-2 on surfaces frequently touched by COVID-19 patients, and assess the scope of contamination and transmissibility in facilities where the outbreaks occurred. In the course of this epidemiological investigation, a total of 80 environmental specimens were collected from 6 hospitals (68 specimens) and 2 "mass facilities" (6 specimens from a rehabilitation center and 6 specimens from an apartment building complex). Specific reverse transcriptase-polymerase chain reaction targeting of RNA-dependent RNA polymerase, and envelope genes, were used to identify the presence of this novel coronavirus.
View Article and Find Full Text PDFAedes albopictus (Skuse, 1894) is a mosquito vector raising global health concerns owing to its transmission of dengue, Zika, and chikungunya viruses. This vector accounts for a large proportion of the Korean mosquito community; however, autochthonous clinical cases resulting from this species remain unreported in South Korea. This study aimed to examine the geographical genetic variations and sources of Ae.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFActa Trop
February 2020
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.
View Article and Find Full Text PDFThe seasonal abundance of Haemaphysalis longicornis Neumann and H. flava Neumann (Acari: Ixodidae) was monitored from 2015 through 2017 in Gyeonggi-do, South Korea. The hard ticks were surveyed monthly using CO2 bait traps from April to November and flagging from July to September in a coniferous forest, a deciduous forest, shrubs, and a grassland vegetation types.
View Article and Find Full Text PDFBackground: As a result of the reintroduction of malaria in the Republic of Korea (ROK) in 1993 and the threat to military and civilian populations, the Korea Military National Defense (MND) increased emphasis on vector control in 2012 at ROK Army (ROKA) installations located near the DMZ, while decreasing chemoprophylaxis, fearing potential drug resistance. Mosquito surveillance demonstrated a need for continuous monitoring of disease patterns among ROKA soldiers and vector malaria infection rates to ensure positive outcomes.
Methods: Anopheles spp.
Japanese encephalitis virus (JEV) causes significant viral encephalitis and is distributed throughout the Asian countries. The virus is known to be transmitted by Culex tritaeniorhynchus, which mainly breeds in rice paddies in Korea. In this study, we investigated the presence of other mosquito species that can transmit JEV as a second or regional vector.
View Article and Find Full Text PDFTo clarify the geographical distribution of scrub typhus vectors in Korea, a survey of larval trombiculid mites was conducted from 2005 to 2007 by collecting wild small mammals twice a year (spring and autumn) at 24 sites nationwide. A total of 67,325 mites representing 4 genera and 14 species were collected from 783 trapped rodents, corresponding to a chigger index (number of chigger mites per rodent) of 86.0.
View Article and Find Full Text PDFOsong Public Health Res Perspect
June 2014
Objectives: Japanese encephalitis is considered as a secondary legal infectious disease in Korea and is transmitted by mosquitoes in the summer season. The purpose of this study was to predict the ratio of Culex tritaeniorhynchus to all the species of mosquitoes present in the study regions.
Methods: From 1999 to 2012, black light traps were installed in 10 regions in Korea (Busan, Gyeonggi, Gangwon, Chungbuk, Chungnam, Jeonbuk, Jeonnam, Gyeongbuk, Gyeongnam, and Jeju) to capture mosquitoes for identification and classification under a dissecting microscope.
We investigated the infection rate for severe fever with thrombocytopenia syndrome virus (SFTSV) among ticks collected from humans during May-October 2013 in South Korea. Haemaphysalis longicornis ticks have been considered the SFTSV vector. However, we detected the virus in H.
View Article and Find Full Text PDFTransovarial transmission of Orientia tsutsugamushi in colonies of Leptotrombidium palpale was studied in the parent and F1 and F2 generations. Both transovarial transmission and filial infection rates were 100% in the parent and F1 generations of Leptotrombidium palpale. The filial infection rate in the F1 generation was 100%, but it declined to 94.
View Article and Find Full Text PDFObjectives: Over 20% of all malaria cases reported annually in the Republic of Korea (ROK) occur in Paju, Gyeonggi Province. Vector control for malaria management is essential, but the insecticide resistance of the vector, Anopheles mosquitoes, has been a major obstacle in implementing effective control. In this study, the insecticide resistance of the vector mosquitoes was evaluated and compared with that of vector mosquitoes collected from the same locality in 2001 and 2009.
View Article and Find Full Text PDFWe investigated the seasonality of Anopheles mosquitoes, including its species composition, density, parity, and population densities of mosquitoes infected with the parasite in Ganghwa-do (Island), a vivax malaria endemic area in the Republic of Korea. Mosquitoes were collected periodically with a dry-ice-tent trap and a blacklight trap during the mosquito season (April-October) in 2008. Anopheles sinensis (94.
View Article and Find Full Text PDFParagonimus westermani is a trematode parasite that causes pulmonary and/or extrapulmonary granulomatous disease in humans. In this study, we identified a full-length gene encoding a novel serine protease inhibitor of P. westermani (PwSERPIN) and characterized the biochemical properties of the recombinant protein.
View Article and Find Full Text PDFWith the current epidemic of vivax malaria closely associated with the demilitarised zone along the border between North and South Korea, it has been suggested that the incubation period tends, in part, to be prolonged. Based on the detailed travel history of cases from 2000 to 2003 who reside in non-malarious areas, statistical estimates of the incubation periods were obtained. The data suggest that cases fall into two categories with short- and long-term incubation periods, respectively.
View Article and Find Full Text PDFIn order to study the range of flight and feeding activity of Anopheles sinensis, the dispersal experiment was conducted in Paju city, located in the northern part of Gyeonggi-do, Republic of Korea, during the period of 7th to 28th September 1998. Unfed females An. sinensis were collected in cowshed and released after being marked with fluorescent dye at 23:00 hours on the same day.
View Article and Find Full Text PDFWe investigated population densities of mosquitoes infected with sporozoites in three highly epidemic areas of Josan-ri and Jangpa-ri (Paju City) and Dongjung-ri (Yeoncheon County) in Korea. Anopheline mosquitoes were collected from both indoors and outdoors by human baiting collection method during the period of the first week of June to the second week of September 1999. Total 13,296 female mosquitoes were collected and 8,650 (65.
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