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Objective To investigate the seasonal Aedes population fluctuation and the resistance of Aedes populations to common insecticides in Jiangsu Province in 2020, so as to provide insights into vector-borne infectious diseases control.. Methods One village was randomly sampled from each of Xinbei District of Changzhou City and Zhangjiagang County of Suzhou City in southern Jiangsu Province, Hai’an County of Nantong City and Yandu District of Yancheng City in Central Jiangsu Province, and Suining County of Xuzhou City and Sihong County of Suqian City in northern Jiangsu Province during the period between May and October, 2020. A small ponding container was sampled, and larval Aedes mosquitoes were collected using straws once each in early and late stages of each month. All larvae were bred in laboratory to adults for population identification. In addition, larval breeding were observed in all small ponding containers in and out of 30 households that were randomly sampled from six surveillance sites, and the larval mosquito density was estimated using Breteau index. Larval A. albopictus mosquitoes were sampled around Cuiyuan New Village in Jintan District of Changzhou City, and bred in laboratory to the first offspring generation, and the susceptibility of adult female mosquitoes to deltamethrin, lambda-cyhalothrin, malathion, and propoxur was tested using the filter-paper bioassay recommended by WHO. Results A total of 1 165 larval Aedes mosquitoes were captured from small ponding containers in six surveillance sites of Jiangsu Province in 2020, and all were identified as A. albopictus following eclosion. The largest number of Aedes larvae captured was found in July. A total of 1 152 households were investigated in six surveillance sites, and the mean Breteau indexes were 9.58, 13.20, 13.71, 13.20, 12.18 and 5.58 from May to October, respectively, while a high Aedes transmission risk was seen in Xinbei District of Changzhou City, with a higher Breteau index than in Suining (H = 23.667, Padjusted = 0.001) and Sihong (H = 22.500, Padjusted = 0.003) counties. The field-captured A. albopictus from Cuiyuan New Village in Jintan District of Changzhou City remained sensitive to malathion, but was resistant to propoxur, and developed high-level resistance to deltamethrin and lambda-cyhalothrin. Conclusions A. albopictus was present in southern, central and northern Jiangsu Province in 2020, and the larval density peaked in July. A. albopictus captured from Cuiyuan New Village in Jintan District of Changzhou City has developed high-level resistance to pyrethroid pesticides.
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Objective To learn the density, distribution, population composition, and seasonal fluctuation of mosquitoes in Shanghai Pudong New Area, and to provide evidence for the mosquito-borne diseases control and prevention. Methods From 2017 to 2019, light trap method was used to monitor the mosquito density in farmyard, parks, hospitals, residential areas and the barns, three times a month from April to November. Results A total of 24 times/set light traps were set up and 7 104 mosquitoes were captured.The average density was 3.07 insects per lamp.Culex pipienspallens (81.52%) and Aedes albopictus (12.10%) were the mostly captured, followed by Armigeres subalbatus (3.24%), Culex tritaeniorhynchus (2.78%) and Anopheles sinensis (0.36%).The proportion of Culex pipienspallens was increasing year by year, and that of Aedes albopictus was decreasing year by year.The seasonal variation curve of mosquito density showed a single peak distribution, with the peak from June to July.Among the five habitat types, the mosquito density from high to low was hospital (4.68/set), farmyard (4.38/set), livestock shed (3.25/set), residential household (2.81/set) and park (1.38/set).The mosquito density in urban area, urban-rural junction and rural area was 2.69, 3.32 and 3.36 respectively (i.e., rural area > urban-rural integration > urban area). Conclusion Culex pipienspallens and Aedes albopictus are the dominant species in Pudong New Area.Parks, hospitals and residential areas are the most important mosquitoes infestation areas, therefore more attention must be paid to mosquito control in these areas.
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Objective To understand the population,density,seasonal fluctuation and nocturnal pattern of malaria vectors in Jiangsu Province,thus to provide evidences for malaria elimination in this province. Methods Seven counties(cities,dis?tricts)were selected as the monitoring sites for malaria vectors in Jiangsu Province from 2013 to 2015. The mosquitoes were cap?tured by human bait trapping in bed nets and mosquito?lured lamp overnight,and the seasonal fluctuation and nocturnal pattern of malaria vectors were observed. Results A total of 11 041 Anopheles sinensis mosquitoes were captured by the mosquito?lured lamps in 7 counties of Jiangsu Province from 2013 to 2015,and no An. anthropophagous was found. Among all the 7 monitoring sites,the number of An. sinensis captured in Sihong County was the most(6 742 mosquitoes),while that in Xuyu County was the least(34 mosquitoes). During this period,the density peaks of An. sinensis were the first half of July,the first half of August and the second half of July. A total of 2 421 An. sinensis were collected in 7 monitoring sites from 2013 to 2015 by human bait trapping in bed nets overnight. Among all the 7 monitoring sites,the captured number of An. sinensis in Sihong County was the most(1 085 mosquitoes),while that in Ganyu County was the least(13 mosquitoes). The nocturnal peak of An. sinensis was from 19:00 to 20:00 and 525 An. sinensis mosquitoes were captured during this period of time,which accounted for 21.68%of the total. Hereafter,the captured number of An. sinensis reduced over time. Conclusion The density of An. sinensis mosquitoes is still high in individual areas in Jiangsu Province,so the epidemic and vector monitoring still should be strengthened to prevent the local transmission of imported malaria.
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Among the edaphic Hexapods, the insects are more abundant and important in that they act as environmental indicators. This study aimed to conduct a survey of the edaphic fauna in a forest fragment of transition from ombrophilous forest to mixed seasonal deciduous forest in the municipality of Anchieta, SC, Brazil. Samples were collected every fortnight from May to August 2010 by using the method of pitfall traps. Were collected 6598 individuals. The groups more abundant was Hymenoptera with 3398 individuals (51%), Collembola with a total of 1370 individuals (21%) and Diptera represented by 910 individuals (14%). The Simpson Index was found 0.60 and the Shannon Diversity Index was 3.00. The results obtained show that the place studied by provide conditions of survival to susceptible species such as Collembola, indicated a good quality of the soil study.
Dentre os Hexapoda edáficos, os insetos são os mais abundantes e de grande importância por atuarem como indicadores ambientais. Esse estudo teve como objetivo realizar um levantamento da fauna edáfica em um fragmento florestal de transição de floresta ombrófila mista para floresta estacional decidual, no Município de Anchieta, SC, Brasil. As coletas foram realizadas quinzenalmente no período de maio a agosto de 2010 utilizando o método das armadilhas de queda tipo pitfall traps. Foram coletados 6598 indivíduos. Os grupos mais abundantes foram Hymenoptera com 3398 indivíduos (51%), Collembola com um total de 1370 indivíduos (21%) e Diptera representada por 910 indivíduos (14%). O valor do Índice de Simpson encontrado foi de 0,60 e o Índice de Diversidade de Shannon de 3,00. Os resultados obtidos mostram que o local estudado por apresentar condições de sobrevivência para espécies sensíveis como os Collembola, indicam uma boa qualidade do solo da área estudada.
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Taxonomical composition and abundance of the planktonic ciliate assemblage in a Lake Tezozomoc, a hypertrophic pond located into an urban park in Mexico City, was investigated along the rainy season (May to October). The aims of the study were to know the main trophic roles and ecological significance of ciliates in a highly productive environment. A low number of taxa (27) and a wide abundance fluctuation (104-387 cil ml-1) were found. The most abundant species (up to 162 cil ml-1) was Halteria grandinella, an oligotrich ciliate that graze on bacteria and picoplankton, but also several big body sized species that feed on pico and nanoplankton were abundant. Sudden temporal changes in species dominance occurred. Ciliate biomass was very high and fluctuated widely (1.6-88 106 ?m3 ml-1) being dominated by the >50 ?m size fraction that mainly included the pico and nanoplankton feeders. Ciliates are a very important component in the plankton of hypertrophic lakes and their main control factor seems to be the grazing by big-body size Daphnia species.
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As espécies do gênero Chrysomya Robineau-Desvoidy 1830 (Diptera: Calliphoridae) exercem papel importante na saúde pública por causarem miíases e por veicularem enteropatógenos. Este estudo visou estimar a abundância relativa e a sazonalidade das três espécies de Chrysomya (C. albiceps, C. putoria e C. megacephala) que ocorrem no Pantanal. Os dípteros foram capturados em quatro armadilhas orientadas pelo vento (Wind Oriented Trap - W.O.T.), iscadas com fígado bovino deteriorado. As armadilhas foram mantidas ativas durante todo o estudo, realizado na fazenda Nhumirim, base experimental da Embrapa Pantanal, sub-região da Nhecolândia, Pantanal Sul-Mato-Grossense. No período de dezembro/2004 a novembro/2007, foram capturados 159.086 espécimes de Calliphoridae, sendo 31,87 por cento do gênero Chrysomya. A espécie mais abundante do gênero foi C. albiceps (30,86 por cento), seguida de C. megacephala (0,67 por cento) e C. putoria (0,34 por cento). As três espécies apresentaram flutuações sazonais semelhantes, com dois picos populacionais anuais, observados entre junho e agosto e entre outubro e dezembro.
Species of the genus Chrysomya Robineau-Desvoidy 1830 (Diptera: Calliphoridae) play an important role in public health due to myiasis and transmission of enteropathogens. This study aimed to estimate the relative abundance and seasonality of the three Chrysomya species (C. albiceps, C. putoria, and C. megacephala) that occur in the Pantanal region. The flies were caught by four Wind Oriented Traps, baited with decayed bovine liver. Traps were kept active all over the study carried out from December 2004 to November 2007 at Nhumirim ranch, located at the Nhecolândia subregion, Southern Pantanal. A total of 159,086 Calliphoridae flies were collected and 31.87 percent of them belonged to the genus Chrysomya. Among calliphorid dipterans the most abundant species was C. albiceps (30.86 percent), followed by C. megacephala (0.67 percent), and C. putoria (0.34 percent). The three Chrysomya species showed similar seasonal fluctuations with two annual population peaks observed in June-August and October-December.