Abstract:Objective To understand the population composition and seasonal fluctuation of mosquitoes,flies,and cockroaches at the Guangdong-Macao In-Depth Cooperation Zone in Hengqin,2024,so as to provide scientific basis for control and prevention of vector and vector-borne diseases.Methods The investigation of adult mosquitoes were conducted using the human landing catch method,larvae mosquitoes using the route method,flies using sweep nets method,and cockroaches using artificially collected at night.Results A total of 2 190 mosquitoes were collected,including 562 adults and 1 628 larvae,were identified as belonging to 3 subfamilies,8 genera,and 17 species,and Aedes albopictus and Armigeres magnus were both the dominant species.There were two peak periods for adult mosquito occurred in May and October,respectively.A total of 895 flies were collected and identified as belonging to 5 families,43 genera,and 71 species,with Chrysomya megacephala,Seniorwhitea princeps,Parasarcophaga brevicornis,and Hemipyrel lialigurriens being the dominant species.The peak period for fly population was from August to October.A total of 1 019 cockroaches were collected and identified as belonging to 3 families,14 genera,and 21 species,with Rhabdoblatta parvula,Blata vilis,Blattella bisignata,Opisthoplatia orientalis,Periplaneta americana,Pycnoscelus surinamensis,B.singularis,and B.germanica being the dominant species.The peak period for cockroach population was from May to July.Conclusion The Guangdong-Macao In-Depth Cooperation Zone in Hengqin is rich in mosquitoes,flie,and cockroaches,and there are obvious seasonal fluctuations.Targeted prevention and control measures should be taken for controlling these three vectors.

Abstract:Objective To analyze the epidemiological characteristics of hemorrhagic fever with renal syndrome(HFRS)in humans and the surveillance of host animals in Gaochun District,Nanjing,from 2018 to 2023,so as to provide scientific evidence for the development of effective HFRS prevention and control strategies.Methods In Gaochun District,the incidence patterns and epidemic behavior of HFRS,along with serological findings related to hantavirus antibodies in the local population,were examined using descriptive epidemiological approaches.The species,density,and hantavirus infection of host animals were also analyzed.The Chi-square test was used for the comparison of rates,and the Spearman correlation analysis was performed to assess the correlation analysis.Results From 2018 to 2023,a total of 119 HFRS cases were reported in Gaochun District,with an average annual incidence rate of 4.49 per 100 000 population.The incidence demonstrated a bimodal seasonal distribution,with peaks occurring in the spring-summer and winter-spring periods,predominantly in the former.Cases were primarily concentrated in Dongba Street(7.45 per 100 000 population),Yaxi Street(7.11 per 100 000 population),Gubai Street(6.94 per 100 000 population),and Qiqiao Street(6.86 per 100 000 population).The incidence rates were significantly higher among male(male:5.34 per 100 000 population,female:3.61 per 100 000 population;x2=4.399,P=0.036)and older age groups(top 3 age groups:17.08 per 100 000 population of 80-84 age group,8.55 per 100 000 population of 70-74 age group,and 6.84 per 100 000 population of 55-59 age group).The occupation of cases was mainly farmers(63.86％).Spatiotemporal scan analysis(RR=5.71,LLR=8.88,P=0.033)identified a significant clustering of cases among Dongba Street,Yaxi Street,and Qiqiao Street during the period from March 1 to June 30,2019.Host animals surveillance revealed an average density of 3.93％,with the highest density recorded in 2019(8.27％)and the lowest in 2023(1.50％).Overall,rodent density was higher in spring than in autumn.The hantavirus carriage rate among rodents was 0.64％,with an infection rate of 3.69％.The predominant rodent species in residential and field environments were Mus musculus(60.38％)and Rattus norvegicus(54.55％),respectively,with M.musculus dominating in both spring(45.45％)and autumn(64.52％).Serological surveillance in humans showed an average IgM positivity rate of 0.16％and an IgG positivity rate of 1.50％in Gaochun District,Nanjing,from 2018 to 2023.Conclusion The incidence rate of HFRS in Gaochun District has exhibited a fluctuating upward trend in recent years,characterized by a distinct bimodal seasonal pattern.Individuals of older age and those engaged in agricultural activities are at high risk of infection.Continued surveillance of both human and host animals is essential.Comprehensive prevention and control efforts-including rodent eradication,environmental sanitation,public health education,and promotion of vaccination-should be intensified in high-risk areas.Targeted interventions aimed at high-risk populations are necessary to reduce the incidence and transmission risk of HFRS.

Abstract:Objective To investigate the population composition and density dynamics of rodents,mosquitoes,flies,and cockroaches in partial port areas of Jiangsu Province,so as to provide a scientific basis for the targeted prevention and control of vectors.Methods From 2021 to 2024,specialized monitoring of four vectors was conducted,using the night trapping method(for rodents),mosquito light trap method(for mosquitoes),cage trapping method(for flies),and sticky trap method(for cockroaches),respectively.Monitoring habitats included work areas,living areas,and external environments.Seven monitoring sites were set up from 2021 to 2023,and the number increased to eight in 2024.Analysis of variance(ANOVA)was used to compare density differences across different years and habitats.Results For rodents,146 individuals belonging to 4 species were captured,with a total capture rate of 0.12％.Apodemus agrarius was the dominant species(accounting for 50.68％).The capture rate in external environments(0.24％)was significantly higher than that in other habitats,with a statistically significant difference(F=9.521,P=0.006),and the density showed a decreasing trend year by year.For mosquitoes,7 953 mosquitoes belonging to 7 species were captured,with an average density of 3.81 mosquites/(lamp·hour).Culex pipiens pallens was absolute dominant species(accounting for 55.58％),and its seasonal fluctuation showed a unimodal distribution with the peak in July.For flies,16 491 flies belonging to 21 species were captured,with an average density of 7.90 flies/cage.Lucilia sericata was the dominant species(accounting for 32.68％),and density differences across years were statistically significant(F=5.720,P=0.022);the overall seasonal fluctuation showed a unimodal distribution.For cockroaches,442 individuals belonging to 6 species were captured,with an average density of 0.04 cockroaches/paper.Blattella germanica was absolute dominant species(accounting for 85.07％).No significant seasonal variation was observed in cockroach density,which remained at a low level in all monitored months throughout the year.Conclusion Vectors in partial port areas of Jiangsu Province have a stable population distribution,but density differences exist across habitats and years.It is necessary to implement targeted prevention and control measures based on the laws of seasonal fluctuation.

Abstract:Objective To investigate the species composition of rodents and their infection status with Leptospira in the port areas of southern Fujian,so as to provide a scientific basis for the prevention and control of rodents and leptospirosis in the region.Methods Quarterly surveys were conducted in February,May,August,and November 2025 within the port areas of southern Fujian and their surrounding 400-meter radius.Rodents were captured using cage traps and snap traps method.After species identification,kidney and bladder tissue samples were collected.The 16S rRNA gene of Leptospira was amplified by PCR for detection.Results A total of 135 rodents were captured in 2025.The dominant species was Suncus murinus(72.59％),followed by Rattus norvegicus(12.59％).Six samples tested positive for Leptospira,with an overall positive rate of 4.44％.The infection rates varied among the different city ports,with Quanzhou showing the highest rate(11.11％),followed by Zhangzhou(4.65％)and Xiamen(1.54％).16S rRNA typing revealed that all six positive samples were pathogenic Leptospira interrogans.Conclusion The density of rodents in the port areas of southern Fujian meets the industry standard limits.However,given the presence of pathogenic L.interrogans in the local rodent population,especially at some ports such as Quanzhou,which show relatively high infection rates,continuous and targeted surveillance and control of rodents and leptospirosis should be strengthened in these areas.

Abstract:Objective To investigate the resistance levels of Aedes albopictus across Zhongshan from 2020 to 2024,and assess regional variations,so as to provide a scientific basis for control strategies of Ae.albopictus.Methods Larval immersion test and WHO tube bioassays were used to evaluate the resistance levels of Ae.albopictus collected from different towns and districts to carbamate,organophosphate,pyrethroid,and biological insecticides.Results There were differences in insecticide resistance among Ae.Albopictus in different region of Zhongshan.Biological insecticide Bacillus Thuringiensis Israelensis(Bti)demonstrated high sensitivity(resistance ratio＜0.2),while pyrethroids such as permethrin exhibited increasing resistance over time in some areas(resistance ratio＞10).Conclusions Ae.Albopictus larvae in Zhongshan generally had low resistance to temephos,and there were significant regional differences in resistance to permethrin.Ae.Albopictus across the region was sensitive to Bti,supporting its prioritization for vector control.Comparative analysis indicated similarities in resistance profiles between Zhongshan and neighboring regions,suggesting cross-administrative dispersal patterns of Ae.albopictus and highlighting the necessity for strengthened regional collaborative management.It is recommended to suspend the use of highly resistant insecticides and adopt a strategy of alternating sensitive insecticides to delay resistance and reduce environmental risks.

Abstract:Objective To identify rodents in the Junggar Basin using DNA barcoding technology and analyze the genetic diversity and geographical population differentiation characteristics of Dipus sagitta.Methods Rodents were captured in the Junggar Basin in May 2024 using the trap-night method.After preliminary morphological identification,genomic DNA was extracted.PCR amplification of the mitochondrial cytochrome c oxidase subunit Ⅰ(CO Ⅰ)gene was performed,followed by sequencing.Species identification was conducted using BLAST alignment,genetic distance analysis,and maximum likelihood(ML)phylogenetic tree construction,and the results were compared with traditional morphological identification.MEGA X,DnaSP 6.0,and Arlequin 3.1 software were used to analyze the genetic diversity,haplotype distribution,and population differentiation of D.sagitta.Results A total of 28 rodents were captured,and CO Ⅰ gene amplification was successful in 26 samples(632 bp).The agreement rate between DNA barcoding identification results and morphological identification was 84.6％(22/26).Four samples originally identified as Meriones tamariscinus were re-examined and confirmed as M.elibycus.Population genetic analysis of D.sagitta revealed moderate to high genetic differentiation(Fst=0.114-0.751)among populations in Jinghe County,Wusu City,and Shihezi City within the Junggar Basin,with low gene flow(Nm=0.083-1.937);Compared with populations in Qinghai,Gansu,and Inner Mongolia,the degree of differentiation was higher(Fst=0.782-0.996),and gene exchange was scarce(Nm=0.001-0.254).Mismatch distribution analysis indicates that D.sagitta population has not undergone recent expansion events.Conclusion DNA barcoding technology can effectively correct errors in morphological identification,providing molecular evidence for species identification of rodents in the Junggar Basin;the D.sagitta population exhibits significant genetic differentiation,which may be related to geographical isolation and ecological barriers within the basin,offering important insights for the development of plague control strategies.

Abstract:Objective To analyze the density and seasonal fluctuation of cockroaches in Aksu,so as to provide scientific and effective basis for cockroach control in Aksu area.Methods From 2020 to 2024,the adhesive capture method was used to monitor 6 types of environments such as residential areas,hotels,catering enviroments,supermarkets,hospitals and farmers' markets in Aksu.Excel 2021 and SPSS 26.0 softwares were used for data collation and statistical analysis.The Chi-square test was used to compare the differences between group rates or proportions.Results A total of 1 264 cockroaches were captured,with an average annual density of 0.45 animals/sheet.The average annual infestation rate was 14.41％.The density and infestation rate of cockroaches showed a decreasing trend in the past 5 years.The dominant species was Blattella germanica,accounting for 97.86％of the total catches.There was significant difference in cockroach density between 2020 and 2024(x2=700.314,P＜0.001).The cockroach infestation rate in different years was significantly different(x2=175.834,P＜0.001).There was significant difference in cockroach density in different environments(x2=700.314,P＜0.001).There was significant difference in cockroach infestation rate among different environments in 5 years(x2=175.834,P＜0.001).There were cockroach activities in Aksu throughout the year from 2020 to 2024.The density of catering environment was the highest compared with other environments in the same period of the year.The activities of cockroaches in hotels,hospitals and residential areas were relatively stable throughout the year.The overall density level was not high and there were no obvious fluctuations.Conclusion The dominant cockroach species in Aksu was Blattella germanica.From 2020 to 2024,the density and infestation rate of cockroaches showed a decreasing trend.The higher cockroach density was found in catering enviroments,farmers' markets and residential areas.The monitoring and control of cockroach in catering environments,farmers' markets and residential areas should be strengthened.

Abstract:Objective To understand the first interception of the vector Macrocheles muscaedomesticae at Tianjin Port,so as to provide a scientific basis for strengthening the quarantine prevention and control of this mite transmitted into the country through ships and other means of transportation.Methods The morphological characteristics of female M.muscaedomesticae was accurately described through detailed morphological observation.At the same time,combined with DNA barcoding molecular identification technology,the partial sequence of mitochondrial cytochrome c oxidase subunit Ⅰ(CO Ⅰ)gene(DNA barcoding)was determined and analyzed,and a phylogenetic tree was constructed to clarify its taxonomic status.Results The partial sequence of CO Ⅰ gene of M.muscaedomesticae was obtained by PCR amplification of 658 bp,which was compared with the NCBI database and BOLD website,and the results showed that the similarity with the CO Ⅰ gene sequence of M.muscaedomesticae was more than 99％.The phylogenetic tree was constructed and found that it was merged with the species sequence of Macrocheles and separated from other species of Macrocheles.Conclusion The vector mite intercepted for the first time at Tianjin Port was M.muscaedomesticae.Through the description of its morphology and molecular biology,it provides basic information for further research on this mite and biosecurity prevention and control at the port,suggesting that the monitoring and prevention of this mite and related flies need to be strengthened during port quarantine work.

Abstract:Objective To analyze the epidemiological characteristics and the trend of hand,foot and mouth disease(HFMD)in Lingwu,Ningxia,and to propose scientific prevention and control strategies.Methods Data of HFMD cases in Lingwu from 2012 to 2024 were collected.Descriptive epidemiological method was used to analyze the temporal,spatial and population distribution of HFMD in Lingwu.And autoregressive integrated moving average(ARIMA)model was constructed for the prediction analysis.Results The reported incidence of HFMD in Lingwu from 2012 to 2024,with an average reported incidence rate of 77.94/100 000.The lowest reported incidence rate was 6.06/100 000 in 2022,and the highest reported incidence rate was 224.32/100 000 in 2019.Cases were reported throughout the year,and the peak period of incidence was mainly from May to July and September to November.In terms of the population distribution,the susceptible population was mainly children aged 5 and under,and the reported incidence rate of boys was higher than that of girls.The ARIMA model showed that the fitted value of HFMD from 2012 to 2024 was highly consistent with the actual observed value,and the absolute error(MAE=18.78)and the root mean square error(RMSE=34.79)were small,which indicated that the model a good fitting effect and could effectively capture the trend and seasonal characteristics of the data.The prediction results showed that the seasonal fluctuation of HFMD still existed from 2025 to 2027,and the number of cases was stable.Conclusion For the prevention and control of HFMD in Lingwu,a joint prevention and control system centered on"key populations,critical periods,and scientific early warning"should be establish.Priority should be given to the prevention and control work targeting scattered children under the age of 5 and children in nursery and childcare institutions.Proper prevention and control resources and prepare for emergency responses should be allocated before the arrival of the annual dual epidemic peaks in summer and autumn.It is necessary to strengthen the collaboration between the education sector and the health sector to give full play to the effectiveness of the early warning mechanism.

Abstract:Objective To investigate the density,distribution,seasonal fluctuation of chigger mites in Hebi,so as to provide scientific evidence for the tsutsugamushi disease.Methods From 2020 to 2024,night trap method was used to capture rodents and to collect ectoparasites from the body surface of rodents in different sites and habitats in Hebi(at least three habitats were selected every year).Chigger mite specimens were prepared proportionally.The rodent species was identified,and the density,chigger infestation rate,and chigger index were calculated.Results From 2020 to 2024,13 424 rodent traps were placed,a total of 42 rodents were captured with a capture rate of 0.31％.Apodemus agrarius and Mus musculus were the dominant rodent species,accounting for 69.05％.The capture rates were higher in rural residential areas(1.90％),farmland(0.53％),key industry(0.35％)and wasteland(0.29％).A total of 647 chigger mites were collected from rodents.The chigger infestation rate was 13.33％and the chigger index was 15.4.Chigger mites were found on the surface of rodents in farmland,wasteland and orchard.All the chigger mites obtained were Leptotrombidium scutellare which was mainly parasitic on the body surface of Apodemus agrarius.Conclusion There are some natural epidemic foci of tsutsugamushi disease among rodents in Hebi.The main host of tsutsugamushi disease was A.agrarius,and the vectors was L.minuta.

Abstract:Objective To analyze the results of pathogenic surveillance of Yersinia pestis in plague foci in Hebei Province from 2017 to 2024 using the combined detection method of Yersinia selective medium and Pulongya culture medium,and to explore its application effect.Methods The liver and spleen organs from the captured host animals were collected aseptically.They were parallelly imprinted on the Yersinia selective medium and Pulongya culture medium,and cultivated at 28 ℃ for 14 to 24 hours.The specific color reaction of Yersinia selective medium and the characteristic colony morphology of Pulongya culture medium were used for the initial screening of suspicious colonies,combining plague phage lysis test to determine whether it was Y.pestis.Results From 2017 to 2024,a total of 4 473 captured host animals were detected by the combined method of double culture medium.Through cross validation of color reaction and microscopic morphology,three suspicious colonies were initially screened and confirmed as Y.pestis by the plague phage lysis test,with a total positive rate of 0.067％.The three strains of Y.pestis showed typical rose red colonies on Yersinia selective medium.Under the same conditions,the morphological characteristics of bacterial colonies under the microscope were not completely typical in Puronya medium.Conclusion The combined detection method for cross-validation of double culture medium establishes double dimensional interpretation mechanism of"color-morphology",significantly improving the detection efficiency and accuracy.It is recommended to promote the application in plague monitoring.

Abstract:Aedes albopictus is an important vector that can transmit diseases such as dengue fever,Zika virus disease and chikungunya fever.In recent years,its distribution in China has expanded significantly,closely linked to global climate change.This paper reviews the impact of meteorological factors(temperature,precipitation,relative humidity and photoperiod)on the ecological changes of Ae.albopictus.Temperature is a key factor affecting the population dynamics and viral transmission efficiency of Ae.albopictus.The optimal temperatures of egg hatching and development are between 20℃and 30℃.However,when the temperature exceeds 30℃,the development rate from larvae to adults will decrease.Extreme temperatures(≥40℃)have a serious impact on the survival and reproduction of Ae.albopictus,preventing egg hatching and causing developmental stagnation in larvae and adults.Precipitation and relative humidity substantially influence Ae.albopictus reproduction and survival,with favorable conditions driving population growth.Photoperiod regulates seasonal dynamics by inducing diapause.Meteorological change,such as increased temperatures and altered precipitation patterns,may expand the habitat of Ae.albopictus and increase the risk of disease transmission.The interaction of temperature,relative humidity and photoperiod significantly affects the growth,development and reproduction of Ae.albopictus.Understanding the response of Ae.albopictus to meteorological changes is essential for developing effective control strategies.

Abstract:Objective To master the termite damage condition of urban parks and squares in Zhejiang Province,so as to provide basic guarantee for establishing the long-term effect mechanism of termite control.Methods Field surveys were conducted as the primary approach,supplemented by literature reviews and interviews.Results 69.1%of the 1 552 urban parks and squares surveyed were affected by termite infestations,with 7.4%classified as severe and 13.5%as moderate.The main termite species identified included Odontotermes formosanus,Reticulitermes flaviceps,Coptotermes formosanus,and Macrotermes barneyi.Conclusion The termite damage of urban parks and squares is severe and common in Zhejiang Province.Termite control should follow the principle of"enhanced regulation,categorized management,and regional control",eliminate the public safety risk caused by termite damage,and minimize the adverse impacts on plant growth,landscape aesthetics,and the risk of infestation spreading to surrounding environments.

Abstract:Objective To systematically evaluate the potential impact of railway construction on the plague transmission chain based on the characteristics of natural plague foci along the China-Kyrgyzstan-Uzbekistan(CKU)railway route,and establish a multi-dimensional prevention and control framework,so as to provide evidence-based support for public health risk management in cross-border major infrastructure projects.Methods Through literature review,archival data collection,and analysis of reported data from the plague prevention and control management information system,spatial epidemiology and statistical methods were used to analyze the risk of plague occurrence and epidemic along the CKU railway combining with the spatial distribution features of natural plague foci,host animal and vector flea population composition,and ecological environmental factors.Results Plague risk in mountainous foci peaked from June to August,while in desert foci,it was higher in May-June and September.Engineering disturbances led to habitat fragmentation for host species,making construction workers a high-risk group for plague infection.Long-distance cross-regional plague transmission emerged as a new risk factor.Conclusion The ecological compression effects,human mobility,and intensive operations of railway construction locally disrupt the ecological balance of plague hosts and vectors,reduce rodent habitat space and thereby increasing the potential risk of plague transmission.However,by implementing health management,enhancing environmental monitoring,promoting international cooperation,and establishing long-term early warning and emergency response mechanisms,the occurrence and epidemic of plague can be effectively reduced,achieving a positive synergy between health and development.

Abstract:Objective To study the changes in the resistance levels of Aedes albopictus in Hongkou District,so as to provide a reference basis for mosquito control and the use of insecticides.Methods Mosquitoes were collected from one residential community and one park in each of the four directions(east,south,west,and north)of Hongkou District as fixed sampling sites.The larval dipping method recommended by WHO was used to determine the insecticide resistance of larvae Ae.albopictus.The contact tube method was used to determine the insecticide resistance of adult Ae.albopictus.Results The larvae Ae.albopictus showed low to moderate resistance to permethrin,with resistance ratios of 3.35 in 2015 and 14.74 in 2019,respectively.The larvae Ae.albopictus showed low to moderate resistance to fenthion,with resistance ratios of 17.05 in 2019,7.95 in 2021 and 13.99 in 2023,respectively.Except in 2015,the larvae Ae.albopictus showed low resistance to temephos,with resistance ratios of 0.30 in 2015,5.99 in 2019,5.93 in 2021 and 4.26 in 2023,respectively.The larvae Ae.albopictus had developed high resistance to deltamethrin,with resistance ratios of 43.50 in 2015 and 65.03 in 2021.There was no statistical difference in resistance among different insecticides(F=6.041,P=0.128).The adult Ae.albopictus developed resistance to permethrin,deltamethrin,beta-cypermethrin and lambda-cyhalothrin,possible resistance to propoxur,and sensitive to fenitrothion.Conclusion The adult and larvae Ae.albopictus in Hongkou District have developed different levels of resistance to different insecticides.It is recommended to reduce the use of fenthion and pyrethroid insecticides,use insecticides in rotation and alternation,and pay attention to the dosage.Meanwhile,health publicity and residents'awareness of mosquito prevention should be strengthen to achieve safe and sustainable mosquito control.

Abstract:Objective To understand the situation of termite damage in 19 traditional villages in Ninghai County and carry out the comprehensive management of termite damage.Methods On-site investigation of termite damage in ancient buildings and surrounding environment in 19 traditional villages was carried out,and comprehensive management was implemented using insecticide barrier technology and powder spraying methods.Results Among the 19 villages,only one village was not affected by termites.Other villages were affected by varying degrees of termite,of which 10 villages had the infestation rate of 50%or above.Insecticides were applied on the termite-infested parts in 18 villages.After treatment,there was no termite activity and new sign of infestation.Conclusion The traditional villages in Ninghai County are severely affected by termite,the implementation of comprehensive management can effectively control termite damage.

Abstract:Objective To understand the spatiotemporal distribution of the population and density of malaria vectors after malaria elimination in Jiujiang,so as to provide a reference basis for the risk assessment of re-transmission of imported malaria.Methods From 2022 to 2024,4 to 5 different counties(cities,districts)were selected every year.Mosquito vector monitoring was carried out using the all-night light trapping method from June to October.All counties(cities,districts)in the city were covered over a period of 3 years,and the spatiotemporal distribution of Anopheles mosquito populations was analyzed.Results From 2022 to 2024,a total of 13894 mosquitoes were captured at 13 monitoring sites,including 797 An.sinensis,12593 Culex mosquitoes,and 504 Aedes albopictus.The average density of An.sinensis was 3.72 mosquitoes/(light·night).The density of An.sinensis was the highest in the first ten days of June[6.00 mosquitoes/(light·night)]and the lowest in the second ten days of October[1.00 mosquitoes/(light·night)].Among the 13 monitored counties(cities,districts),the average density of An.sinensis was the highest in Yongxiu County and Pengze County[15.05 mosquitoes/(light·night)and 9.63 mosquitoes/(light·night)],and the lowest in Xunyang District[0.90 mosquitoes/(light·night)].The difference was statistically significant(F=5.641,P＜0.001).Among 3 habitats,the density of An.sinensis was the highest in livestock sheds[24.8 mosquitoes/(light·night)],followed by breeding grounds[3.16 mosquitoes/(light·night)],and the lowest in human settlements[1.96 mosquitoes/(light·night)].The difference was statistically significant(F=63.598,P＜0.001).Conclusion The distribution of mosquito populations in Jiujiang was mainly Culex mosquitoes,followed by An.sinensis.The average density of An.sinensis was relatively high in counties such as Yongxiu County and Pengze County.In recent years,the number of imported malaria cases in Jiujiang has significantly increased,and the proportion of vivax malaria cases has also risen.It is necessary to strengthen the monitoring of malaria vectors,take effective vector control measures to reduce the risk of transmission to prevent the secondary cases of malaria importation.

Abstract:Objective To investigate whether ultrasound can effectively repel mosquitoes and to examine the effects of different ultrasound frequencies and power levels on mosquitoes behavioral patterns.Methods Airborne ultrasound at different frequencies(24.5,33,40 kHz)and power levels(5,10,15,20 W)were applied to Armigeres subalbatus within a test chamber.The avoidance rate,leg movement trajectory length,mortality rate,and blood-feeding rate were measured and compared between an ultrasound-treated group and a control group.One-way ANOVA was used to analyze the differences in mosquito behavior affected by ultrasound.Results The results regarding the repellent rate of A.subalbatus showed no significant difference between the ultrasound-treated group and the control group(P＞0.05),indicating that ultrasound did not repel the mosquitoes.However,the experiment on leg movement trajectory length revealed that ultrasound significantly affected this parameter in A.subalbatus,with the trajectory length increasing as both frequency and power increased(P＜0.05).The mortality rate experiment showed that ultrasound could not kill A.subalbatus,with no significant difference in mortality rates observed between the ultrasound-treated and control groups(P＞0.05).Furthermore,the blood-feeding rate experiment demonstrated that ultrasound also failed to reduce the blood-feeding rate of A.subalbatus,with no statistically significant difference between the groups(P＞0.05).Conclusion Commonly used low-frequency airborne ultrasound below 50 kHz does not repel A.subalbatus.Mosquitoes can perceive ultrasound,and their leg vibration amplitude significantly increases with higher frequency and power.However,such ultrasound has no measurable effect on the repellent rate,mortality rate,or blood-feeding rate of A.subalbatus.

Abstract:Objective To analyze epidemiological characteristics of Sichuan Province's first indigenous dengue fever outbreak and evaluate the effect of control measures,so as to provide evidence for scientific control strategies.Methods The investigation employed field epidemiology methods,descriptive epidemiology to analyze outbreak characteristics,and a retrospective cohort study to assess the relationship between exposure frequency and merchant infection rates in flower market A.Vector density was monitored using the Breteau idex and double mosquito-net trap methods,and control measures were evaluated.Results 17 indigenous dengue cases were identified(13 clinically diagnosed,4 laboratory-confirmed),all linked to flower market A in Longmatan District,Luzhou.Cases occurred between August 23 and September 29,2019,showing a second-generation transmission pattern.11 cases were market merchants and family members,with spatial spread from the left to the right side of the market.There was a statisticall significant difference in the incidence rate of merchants with different exposure frequencies(χ2=44.17,P＜0.001).The higher the exposure frequency,the greater the risk of dengue fever.Pre-disinfection container indexes were significantly higher in merchant-affected stalls(43.28)compared to unaffected stalls(30.08)(χ2=456.00,P＜0.05).Conclusion This outbreak,the first indigenous dengue fever event in Sichuan,was linked to exposure to flower market A,with merchant infection risk positively correlated with exposure frequency and container index.The outbreak likely originated from virulent vectors introduced from Guangzhou or Yunnan or an imported case from Cambodia.It is recommended to strengthen the training on dengue prevention and control knowledge in medical institutions,and enhance quarantine measures for aquatic plant and mosquito vector monitoring in key places such as flower markets to ensure early detection and control of the outbreak.

Abstract:Objective To evaluates the efficacy of diatomaceous earth(DE)on Blattella germanica.Methods Under laboratory conditions,forced contact experiments and chain-killing experiments were conducted to assess the insecticidal effects of DE.Results Experimental results showed that there was a significant dose-response relationship between the application dose of DE and mortality.When the application dose was 2 g/m2,the mortality rate reached 100%within 48 hours,while increasing the dose to 3 g/m2 resulted in complete extermination within 24 hours.The chain-killing experiments demonstrated that when the ratio of DE-contaminated donor cockroaches and uncontaminated recipient cockroaches was≥5∶1,the 48-hour mortality rate of recipients reached 50%,confirming the chain-killing effect of DE.DE demonstrates effective control against B.germanica within a relative humidity range of 55%to 84%,achieving a mortality of 100%within 8 hours.Residual efficacy tests indicated that DE retained strong insecticidal activity for up to 60 days post-application,with all cockroaches succumbing within 12 hours of exposure.Conclusion DE exhibits highly efficient and persistent cockroach-killing properties under different humidity conditions.It is of environmentally friendliness and non-resistance risks,providing an innovative solution for establishing sustainable integrated cockroach management strategies.