A seasonal chigger-borne disease surveillance program was established at Geoje in March, April, October, and November, 2023. Three species of 45 wild rodents were collected by using Sherman traps, including Apodemus agrarius (Species Ratio; SR 88.9%), Crocidura spp. (SR 8.9%), Micromys minutus (SR 2.2%) in Geoje, 2023. A total of 2,597 chiggers were collected from three species of the rodents in Geoje. The chigger mites were collected from A. agrarius (Chigger Index; CI 64.9) and C. spp. (CI 0.3) for Geoje. In the collection environments, a total number of 734, 659, 172, 520, and 512 chiggers were collected from a reservoir, a ditch, a rice paddy, a field, and a hill, respectively. In the results of the isolation of Orientia tsutsugamushi from the chigger mites, no pathogens were detected from the DNA of the 62 pools of the mites using a Polymerase Chain Reaction method in 2023.
The vector mosquito surveillance is important when recommending prevention and control measures. The surveillance of the vectors were conducted at a total of 7 locations with light emitting diode (LED traps) and BG-Sentinel traps from March to November, 2023 in Gyeongnam province. In the surveillance, a total of 13 species belonging to seven genera were collected in a total of 6,537 females and 51.9/trap/night (Trap Index; TI) in 2023. Among the collection sites, Gangseo-gu at the pigsty in Busan with a LED trap recorded the highest TI 60.6 (Species Ratio; SR 65.6%) for Culex tritaeniorhynchus females in 2023. Each one of Cx. tritaeniorhynchus female was firstly collected for 2023 at Eulsukdo in Busan at 22th March. In the results of isolation of viral RNA, Flavivirus were positive in one pool (Chaoyang virus; 30 individuals) of Aedes vexans and negative in 341 pools (4,152 individuals) of 12 mosquito species including Cx. tritaeniorhynchus, Cx. pipiens, Aedes vexans, Ae. albopictus, and Ochlerotatus togoi in 2023.
A seasonal chigger-borne disease surveillance program was established at Geoje from March to November of 2018 in Gyeongnam Province, Republic of Korea. Two species of 84 wild rodents were collected by using Sherman traps for Geoje in 2018. Chigger mites were collected from the live-captured rodents to figure out seasonal prevalence of mite species and to identify chigger-borne pathogens. A total of 4,611 chiggers were collected from two species of the rodents in 2018. The chigger mites were collected mainly from A. agrarius (Chigger Index; CI 68.3). A vector of scrub typhus, Leptotrombidium orientale was predominant species (CI 14.9, Species Ratio; SR 27.2%) followed by L. pallidium (CI 14.2, SR 25.9%) and L. scutellare (CI 13.2, SR 24.2%) in 2018. In the results of the isolation of Orientia tsutsugamushi from the chigger mites, no pathogens detected from the DNA of the 171 pools of the mites in 2018, using a Polymerase Chain Reaction method.
Surveillance of the vectors were conducted at a total of 7 locations from March to November, 2018 in Gyeongnam province. In the surveillance, a total of 13 species belonging to seven genera were collected in a total of 15,935 females and 126.5/trap/night (TI; Trap Index) in 2018. Among the collection sites, a bird refuge in Busan, Eulsukdo recorded the highest TI 230.4 (Species Ratio; SR 60.1%) for Cx. tritaeniorhynchus females in 2018. A Cx. tritaeniorhynchus female collected firstly for 2018 in the nation at the pigsty of Busan at 1st April. In the results of isolation of viral RNA from 12 mosquito species including Cx. tritaeniorhynchus, Cx. pipiens, Ae. vexans, Ae. albopictus, and Oc. togoi. Chaoyang virus was positive at a pool of Ar. subalbatus collected at a bird refuge but negative in the other 543 pools (14,295 individuals) in 2018.
Population density of Culex tritaeniorhynchus was annually monitored to predict the possibility of a Japanese encephalitis (JE) outbreak at 10 collection sites throughout Republic of Korea (ROK) during mosquito season from 2011 to 2015. Prevalence of Cx. tritaeniorhynchus in ROK was spatially and timely very variable and was significantly highest at Busan city during August. Monthly average population density of Cx. tritaeniorhychus showed high correlation to the monthly average daily average temperature and monthly average precipitation. Two models for the estimation of occurrence of Cx. tritaeniorhynchus based on annual monthly daily average temperature and monthly precipitation are shown with linear regression equations of exp(0.413×temperature-0.949) and exp(0.01258×precipitation+3.777). JE vector surveillance and vector control is warranted as part of an effective JE management program at ROK.
본 연구는 김포시에서 모기성충의 계절적 발생소장과 얼룩날개모기류 유충의 발생을 파악하기 위해서 실시되었다. 성충모기는 6지점에서 유문등을 이용하여, 2008년 5월부터 9월까지 조사되었다. 조사결과 8속 16종 48,919마리가 채집되었다. 금빛숲모기(Aedes vexans nipponii)가 43%로 가장 많았고, 중국얼룩날개모기(Anophels sinensis)가 34%, 작은빨간집모기(Culex tritaeniorhynchus)가 14%로 이 3 우점종이 전체의 91%를 차지했다. 얼룩날개모기류의 계절적 발생소장은 작은빨간집모기와 비교하여 다른 피크를 보였다. 얼룩날개모기류 유충은 203지점 중 138지점(63%)에서 확인되었다. 지점당 정량조사 결과에서 평균유충밀도는 연꽃 재배지가 6.9개체로 가장 높았으며, 다음으로 수로가 4.5개체, 미나리꽝이 3.4개체, 유수지가 3.2개체, 휴경논이 3.1개체, 논이 1.8개체, 습지가 1.4개체, 하천이 0.2개체 순이었다. 유충밀도와 용존산소량, 산도, 염분도, 흡밀원(축사, 돈사, 계사) 사이에 유의한 관계성은 없었다. 최근린평균거리분석(ANNA)의 결과에서, 유충 조사지점간 분포패턴은 전체 조사지점간과 4.0개체 이상 확인된 지점간에서 각각 밀집분포와 불규칙분포였다. 하성면에서는 유충이 3.0 개체 이상 확인된 지점간 분산분포를 나타냈다.
The bean pyralid, Omiodes indicatus (Fabricius), moulted 4 times during larval period. When temperature increased from 15 to 20, 25, and 30℃, the developmental period of immature stages was shortened, 18.2, 7.5, 5.0, and 4.1 days of egg period, 51.8, 20.0, 12.7, and 9.9 days of larval period, 29.5, 12.0, 8.0, and 5.9 days of pupal period, respectively. Adult longevity was 16.0, 14.7, 11.2, and 7.5 days at respective temperatures. A female adult layed 57.0, 63.3, 82.2, and 31.7 eggs in 3.7, 6.0, 5.8, and 3.0 days of oviposition period at the same temperature regimes, respectively. Field survey in 2006 and 2007 showed that leaf damage on paddy field and upland soybeans began to appear in mid July, reaching its peaks in mid August and late September. Adults of the bean pyralid appeared in mid July and peaked in late August and early October.
울산시 울주군 청량면 인근 해안가 주변의 저습지를 보유한 용암리에 서식하는 모기의 계절적 발생소장을 조사하였다. 성충 채집은 Nozawa 유문등을 이용하여 3년(1999-2001) 동안 3월부터 9월까지 두 곳의 우사에서 격주에 한번씩 암컷을 대상으로 실시하였다. 채집된 암컷 성충은 1999년에 트랩당 평균 4,416.1마리, 2000년에 5,505.9마리, 그리고 2001년에 6,863.8마리였다. 채집된 모기의 종류는 5속 10종이었으며, 가장 높은 채집수를 보인 종은 중국얼룩날개모기로 종비는 53.4%였으며 다음으로 작은빨간집모기(43.0%), 이나도미집모기(1.6%), 등줄숲모기(1.3%), 빨간집모기(0.5%) 순이었다. 말라리아 매개모기인 중국얼룩날개모기와 일본뇌염 매개모기인 작은빨간집모기의 주요발생 시기인 6월부터 9월까지의 트랩당 평균 채집수는 각각 3,663.3마리와 3,142.5마리였다. 1997년 조사에서 우점종으로 나타난 이나도미집모기의 채집수는 연중 7월 초순에 가장 높게 나타났다.
This study focuses on the fauna, seasonal prevalence and altitudinal distribution of the flies from March to November, 2008 in Mt. Hallasan, Jejudo Island, Korea. The fauna of flies was 39 species belonging to 5 Families which consist of 12 Calliphoridae, 19 Muscidae, 5 Sarcophagidae, 1 Dryomyzidae 1, Scathophagidae and 1 Anthomyiidae. The total number of flies collected was 21,605 with sex ratio of 57.98% in Mt. Halla. The ratio is higher than that of the residential area and other mountain survey sites. The average number of per trap individuals collected on the trapping day is 267, which is similar with the average of Mts. Jiryong, Juwang, Palgong and Gumo. The five dominant species showed a distinctive seasonal prevalence of 92.6% of the total flies: Chrysomyia pinguis (34.2%), Calliphora lata (25.3%), Hydrotaea dentipes(23.1%), Fannia scalaris (5.1%), and Lucilia caesar (4.9%). The seasonal prevalence of the flies was from the beginning of March to the end of November, and the highest peak time of the whole flies, males and females were different respectively. In the similarity index of the flies collected in different altitude, that of between 1,000 meters and 1,500 meters was the highest among the indices of 500 meters and above 1,000 meters. The index at each altitude was above 80% because of the same area. The diversity index of fly species was between 0.00 and 0.88 through altitudinal traps monthly. The highest index in Trap 1 was 0.88 in October, in Trap 2, 0.82 in July and in Trap 3, 0.63 in July. The diversity above 1,000 meters was most various in July. The five dominant species of C. pinguis, C. lata, H. dentipes, F. scalaris, and L. caesar showed distinctive seasonal prevalence, relative abundance and altitudinal distribution respectively.
The total number of flies collected was 4,864 with sex ratio of 32.8% from Suseungdae area, Geochang-gun, Gyeongnam, Korea. The fauna of fly was 35 species consisting of 13 Calliphoridae, 12 Muscidae, 8 Sarcophagidae, 1 Dryomyzidae and 1 Anthomyiidae. The number of genus and species of Calliphoridae and Muscidae of Suseungdae area were similarly found in the mountain and residential areas, however, those of Sarcophagidae was similar with that of residential area. Calliphoridae was the most dominant family at the survey sites with 60.4% of the total collected flies, and followed Muscidae 33.3% and Sarcophagidae 6.2%. The dominant species were constituted of 83.6% of the total flies and the order of collected flies was Chrysomyia pinguis (42.2%), Limnophora sp. (10.8%), Muscina angustifrons (8.6%), Calliphora lata (8.1%), Fannia scalaris (5.5%), Lucilia caesar (3.9%), and Boettcherisca peregrina (4.2%). The seasonal prevalence of flies was from the middle of March to the end of November, and the peak time of appearance was the middle of June, middle of September and middle of October. The highest peak of prevalence was the middle of October. The similarity index of the flies was above 80%, compared to Mt. Geonheung and landfill in Geochang-gun. The number of fly species was more affected by the mean air temperature. In the comparison of the seasonal prevalence and relative abundance of 7 predominant species among 35 species, each species was found to exhibit its specific characteristics and showed the pattern of species.