Objective Stagnant water in flower vases in a cemetery can become a breeding ground for mosquitoes,especially in warm and humid climates.The purpose of this survey is to determine whether the physical characteristics ...Objective Stagnant water in flower vases in a cemetery can become a breeding ground for mosquitoes,especially in warm and humid climates.The purpose of this survey is to determine whether the physical characteristics of the flower vases affect mosquito breeding.Methods The physical characteristics of a total of 527 flower vases and their impact on mosquito breeding were investigated in an old cemetery in Gainesville,Florida,during summers from 2000 to 2003,intermittently.Results The vases were categorized into five types based on their shape and material.Approximately 94.1%(496)of vases were made of stone,3.2%(17)were made of glass,1.9%(10)were made of metal,and 0.8%(4)were made of plastic or other materials.Approximately 44.6%(235/527)of the vases or containers were located in shady areas,most of which were under trees.Approximately 17.3%(91/527)of vases and containers held water,ranging from 100 mL to 1000 mL.About 48.4%(44/91)of the water-holding containers presented mosquito larvae.They were Aedes aegypti(5%),Aedes albopictus(60%),Aedes triseriatus(30%),Culex quinquefasciatus(2%),and Toxorhynchites.rutilus(2%).In addition,the prevention and management of mosquito breeding in cemetery flower vases have been proposed and discussed.Conclusions The physical characteristics of the flower vases impacted the container-inhabiting mosquitoes in the old urban cemetery.展开更多
Objective:To identify the efficacy of Wolbachia-based intervention by reviewing community-based trials through meta-analysis and systematic review methods.Methods:Studies about Wolbachia-infected mosquito intervention...Objective:To identify the efficacy of Wolbachia-based intervention by reviewing community-based trials through meta-analysis and systematic review methods.Methods:Studies about Wolbachia-infected mosquito intervention were collected through a screening process.Records underwent data extraction and quality assessment independently by the authors.The primary outcome of the study was protective efficacy.Quantitative analysis was conducted through meta-analysis and multivariate meta-regression using Rstudio Ver.2024.09.0-375.Qualitative analysis was done by summarizing records’findings.Results:10 out of the 10660 records met the criteria.The evidence was moderate in quality and highly heterogeneous.Intervention consisted of releasing Wolbachia-infected Aedes aegypti in densely populated settlements.The combined protective efficacy of Wolbachia intervention against dengue is highly heterogeneous(79%;95%CI 70-88;I^(2)=98%).wMel strain is significantly more efficacious compared to wAlbB(protective efficacy 84%;95%CI 76-93;I^(2)=95%)vs.64%(95%CI 46-82;I^(2)=85%);P<0.01)in preventing dengue cases.Wolbachia-infected mosquito populations were found to be unstable upon release cessation,which necessitated periodic release and monitoring to maintain desired concentration and protective efficacy.Conclusions:Wolbachia-based intervention is effective in suppressing the transmission of mosquito-borne diseases,especially dengue,with an excellent safety profile.However,community acceptance and policy remain as significant barriers to implementation.展开更多
Dear Editor,Viruses transmitted by arthropods(arboviruses)are highly diverse,both genetically and in terms of host insect species.They are widely distributed across the virosphere,with significant representation in th...Dear Editor,Viruses transmitted by arthropods(arboviruses)are highly diverse,both genetically and in terms of host insect species.They are widely distributed across the virosphere,with significant representation in the family Rhabdoviridae,which encompasses a total of 580 different species divided into 4 sub-families and 62 genera(ICTV:https://talk.ictvonline.org/)(Kuhn et al.,2023;Walker et al.,2022).展开更多
Background:This article examines the impact of the release of Wolbachia-infected population replacement mosquitoes as an innovative strategy for managing and controlling dengue in the Americas,using an approach based ...Background:This article examines the impact of the release of Wolbachia-infected population replacement mosquitoes as an innovative strategy for managing and controlling dengue in the Americas,using an approach based on the system dynamics methodology.The introduction of Wolbachia-carrying mosquitoes aims to reduce dengue transmission by interfering with the reproductive capacity of mosquitoes,thus limiting the spread of the virus.Objective:the objective of this study is to analyze how this intervention affects not only the incidence of dengue but also the health care system,evaluating changes in the demand for medical services and the costs associated with treatment in health care institutions.Specifically,it looks at the cost per visit to an Epidemiologist,a Family Doctor,diagnostic tests,and hospitalization.Methods:the study uses simulation scenarios to model the potential impact of the Wolbachia-based intervention in reducing dengue cases and its associated health and economic burden.The scenarios also assess the optimization of resources and improvements in the health system’s response to epidemic outbreaks.The simulation model utilizes real data from the Americas region to enhance the accuracy and relevance of the results.Conclusion:The results the potential of the release of Wolbachia-carrying mosquitoes to significantly mitigate the health and economic burden of dengue,with a maximum saving of 60.15%in the best simulation scenario.The approach not only highlights scientific innovation but also demonstrates its potential influence on public policy design.The findings support the implementation of sustainable strategies to maximize the benefits of this intervention and ensure its effective integration into public health programs,contributing to better long-term dengue management.展开更多
Malaria is a significant global health challenge.This devastating disease continues to affect millions,especially in tropical regions.It is caused by Plasmodium parasites transmitted by female Anopheles mosquitoes.Thi...Malaria is a significant global health challenge.This devastating disease continues to affect millions,especially in tropical regions.It is caused by Plasmodium parasites transmitted by female Anopheles mosquitoes.This study introduces a nonlinear mathematical model for examining the transmission dynamics of malaria,incorporating both human and mosquito populations.We aim to identify the key factors driving the endemic spread of malaria,determine feasible solutions,and provide insights that lead to the development of effective prevention and management strategies.We derive the basic reproductive number employing the next-generation matrix approach and identify the disease-free and endemic equilibrium points.Stability analyses indicate that the disease-free equilibrium is locally and globally stable when the reproductive number is below one,whereas an endemic equilibrium persists when this threshold is exceeded.Sensitivity analysis identifies the most influential mosquito-related parameters,particularly the bite rate and mosquito mortality,in controlling the spread of malaria.Furthermore,we extend our model to include a treatment compartment and three disease-preventive control variables such as antimalaria drug treatments,use of larvicides,and the use of insecticide-treated mosquito nets for optimal control analysis.The results show that optimal use of mosquito nets,use of larvicides for mosquito population control,and treatment can lower the basic reproduction number and control malaria transmission with minimal intervention costs.The analysis of disease control strategies and findings offers valuable information for policymakers in designing cost-effective strategies to combat malaria.展开更多
RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied ...RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied in the treatment of human diseases and crop protection against insect pests[2-4].With the availability of the full genome sequences of major mosquito vectors,RNAi has become increasingly used as a novel means of mosquito control[5].展开更多
[Objective] The aim was to understand the species composition, distribution, density, seasonal fluctuation and pathogens of mosquitoes in four regions of East China to provide basic data for prevention and control of ...[Objective] The aim was to understand the species composition, distribution, density, seasonal fluctuation and pathogens of mosquitoes in four regions of East China to provide basic data for prevention and control of mosquitoes at ports. [Method] The mosquitoes at 21 ports of four regions in East China were investigated during 2011-2014 by CO2 lamp method, egg collection method, scoop method and visual method. The species of mosquitoes was identified, and pathogens in mosquitoes were detected. [Result] From 2011 to 2014, 102 583 mosquitoes were captured at the ports, belonging to 18 species, 6 genera and 1 family. Culex pipi- ens quinquefasciatus or Culex pipiens pallens was the dominant species at most ports. Mosquitoes could be captured from May to October, and the captured mosquitoes were the most in June. The positive rate of egg collectors was 9.41%, and the positive rate of breeding places was 7.23%. Rare entry mosquitoes were captured, and most of them were C. pipiens pallens. The detection results of dengue fever, malaria and other pathogens were negative. [Conclusion] C. pipiens quinquefasciatus or C. pipiens pallens was dominant at most ports, and the peak period was June. There were breeding environments of mosquitoes at some ports, so the prevention and control of mosquitoes at these ports should be paid more at- tention to in future.展开更多
Variables among the macroclimate, microclimate and rice canopy categories and three other different farming systems were evaluated on their effects to the egg and larval density of Aedes spp. mosquitoes known as trans...Variables among the macroclimate, microclimate and rice canopy categories and three other different farming systems were evaluated on their effects to the egg and larval density of Aedes spp. mosquitoes known as transmitters of animal and human diseases. No statistical difference in egg density (#eggs/mL) among farming systems (P = 0.345) were observed. However, there was significant difference in larval density (#1arvae/mL) among farming systems (P 〈 0.001) particularly between organic and conventional farms and between organic and mixed farms at (P 〈 0.05). Among the variables in the macroclimate category, wind velocity and ambient temperature significantly influenced larval density in conventional farms. Among the variables in the microclimate category, water temperature significantly contributed to larval density in both the mixed and conventional farms whereas water turbidity, in conventional farms. Among the variables in the rice canopy category, the number of tillers per plant was a significant contributor to larval density in all farm types. No variable among the environmental exposure categories affected the larval density in organic farms.展开更多
Dengue fever is an acute infectious disease caused by the dengue virus and transmitted by mosquito vectors[1].Its clinical manifestations include high fever,headache,muscle and joint pain,and rash.It holds a significa...Dengue fever is an acute infectious disease caused by the dengue virus and transmitted by mosquito vectors[1].Its clinical manifestations include high fever,headache,muscle and joint pain,and rash.It holds a significant position in global public health.In recent years,its incidence has continued to rise worldwide[2],making it one of the major diseases threatening human health.The disease course of dengue fever is divided into three typical phases:the acute febrile phase,the critical phase,and the recovery phase.While most patients experience mild symptoms,some may progress to severe dengue and potentially fatal outcomes if not promptly and effectively treated during the critical phase.展开更多
[Objective] The study aimed to solve the problem of morphological identi- fication difficulties and propose solutions for the identification of foreign mosquitoes that are difficult to identify. [Method] Based on the ...[Objective] The study aimed to solve the problem of morphological identi- fication difficulties and propose solutions for the identification of foreign mosquitoes that are difficult to identify. [Method] Based on the sequencing, alignment and anal- ysis of COl gene fragment, DNA barcode technology was used to identify 7 exotic mosquitoes, and the phylogenetic analysis was performed using MEGA6.0 and DNASTAR software. Then the morphological characteristics of the mosquitoes were reviewed. [Result[ These mosquitoes were Armigeres subalbatus, Culex gefidus, Anopheles gambiae, and Culiseta incidens. [Conclusion] DNA barcode technology is a useful supplement to the morphological classification method of mosquitoes.展开更多
Mosquitoes are exceptional in their ability to pierce into human skin with a natural ultimate painless microneedle, named fascicle. Here the structure of the Aedes albopictus mosquito fascicle is obtained using a Scan...Mosquitoes are exceptional in their ability to pierce into human skin with a natural ultimate painless microneedle, named fascicle. Here the structure of the Aedes albopictus mosquito fascicle is obtained using a Scanning Electron Microscope (SEM), and the whole process of the fascicle inserting into human skin is observed using a high-speed video imaging technique. Direct measurements of the insertion force for mosquito fascicle to penetrate into human skin are reported. Results show that the mosquito uses a very low force (average 18 μN) to penetrate into the skin. This force is at least three orders of magnitude smaller than the reported lowest insertion force for an artificial microneedle with an ultra sharp tip to insert into the human skin. In order to understand the piercing mechanism of mosquito fascicle tip into human multilayer skin tissue, a numerical simulation is conducted to analyze the insertion process using a nonlinear finite element method. A good agreement occurs between the numerical results and the experimental measurements.展开更多
Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefa...Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefasciatus(Cx.quinquefasciatus) and Aedes albopictus(Ae.albopictus) in India.Methods:The R.communis seed extract was tested,employing WHO procedure,against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations(2-64μg/mL):the 24 h LC<sub>50</sub> values of the R.communis seed extract were determined following Probit analysis.The larval killing,antipupation and adult emergence inhibition rates of the test extract,using a single concentration of 2μLC<sub>50</sub>,were studied at different time periods(24-72 h):the extract toxicity was tested against a fish.Oreochromis niloticus(O.niloticus).Results:The R.communis seed extract exhibited larvicidal effects with 100%killing activities at concentrations 32-64μg/mL,and with LC<sub>50</sub> values 7.10.11.64 and 16.84μg/mL for Cx.quinquefasciatus,An.stephensi and Ae.albopictus larvae,respectively. When the larvae were treated with the extract at a single concentration of 2×LC<sub>50</sub>,significant differences were observed,compared to control groups,in rate of pupation(P【0.001) as well as in adult formation(P【0.001).Conclusions:The present findings suggest that the R.communis seed extract provided an excellent potential for controlling An.stephensi,Cx.quinquefasciatus and Ae. albopictus mosquito vectors.展开更多
Objective:To determine the mosquito larvicidal activity of leaf essential oil and their chemical constituents from Clausena anisata(C.anisata)(Willd.) Hook.f.ex Benth.against Culex quinquefasciatus,Aedes aegypti a...Objective:To determine the mosquito larvicidal activity of leaf essential oil and their chemical constituents from Clausena anisata(C.anisata)(Willd.) Hook.f.ex Benth.against Culex quinquefasciatus,Aedes aegypti and Anopheles Stephensi.Methods:Essential oil was obtained by hydro-distillation and the chemical composition of the leaf essential oil was analyzed using gas chromatography—mass spectrometry.The mosquitoes were reared in the vector control laboratory and twenty lateⅢinstar larvae of three mosquito species were exposed to based on the wide range and narrow range tests,essential oil was tested at 50.100.150,200 and 250 ppm and each compound was tested at various concentration(5-75 ppm) and were assayed in the laboratory by using the protocol of WHO 2005:the 24 h LC<sub>50</sub> values of the C.anisata leaf essential oil and their major compounds were determined following Probit analysis.Results:The oil contained were mainlyβ-pinene(32.8%),sabinene(28.3%),germacrene-D(12.7%),estragole (6.4%) and linalool(5.9%).The essential oil from the leaves of C.anisata exhibited significant larvicidal activity,with 24 h LC<sub>50</sub> values of 140.96,130.19 and 119.59 ppm.respectively.The five pure constituents extracted from the C.anisata leaf essential oil were also tested individually against three mosquito larvae.The LC<sub>50</sub> values ofβ-pinene,sabinene,germacrene-D,estragole and linalool appeared to be most effective against Anopheles stephensi(LC<sub>50</sub>-23.17,19.67,16.95. 11.01,35.17 ppm) followed by Aedes aegypti(LC<sub>50</sub>-27.69,21.20,18.76,12.70,38.64 ppm) and Culex quinquefasciatus(LC<sub>50</sub>-32.23,25.01.21.28,14.01,42.28).Conclusions:The essential oil of C. anisata contains five major compounds and has remarkable larvicidal properties,which may be considered as a potent source for the production of natural larvicides.展开更多
Objective:To determine the larvicidal and repellent activities of Sida acuta Burm.F.(Family: Malvaceae)extract against Culex quinquefasciatus,Aedes aegypti and Anopheles stephensi. Methods:Twenty five late III insta...Objective:To determine the larvicidal and repellent activities of Sida acuta Burm.F.(Family: Malvaceae)extract against Culex quinquefasciatus,Aedes aegypti and Anopheles stephensi. Methods:Twenty five late III instar larve of three mosquito species were exposed to various concentrations(15-90 mg/L) and were assayed in the laboratory by using the protocol of WHO 2005:the 24 h LC<sub>50</sub> values of the Sida acuta leaf extract was determined following Probit analysis. The repellent efficacy was determined against three mosquito species at three concentrations viz.,1.0,2.5 and 5.0 mg/cm<sup>2</sup> under the laboratory conditions.Results:Results showed varying degree of larvicidal activity of crude extract of Sida acuta against three important mosquitoes with LC<sub>50</sub> values ranging between 38 to 48 mg/L.The crude extract had strong repellent action against three species of mosquitoes as it provided 100%protection against Anopheles stephensi for 180 min followed by Aedes aegypti(150 min) and Culex quinquefasciatus(120 min).Conclusions: From the results it can be concluded the crude extract of Sida acuta was an excellent potential for controlling Culex quinquefasciatus,Aedes aegypti and Anopleles stephensi mosquitoes.展开更多
Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact ...Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact of effluents from the firms.Methods:Third instars larvae were sampled by standard dipping method and lead concentrations in the larvae and their respective surrounding factory aquatic environments were determined through standard atomic absorption spectrophotometry(AAS).Results:Cx.quinquefasciatus was the most abundant species followed by Cx.gelidus.The levels of lead were higher in the Cx.quinquefasciatus(1.08-47.47μg/g),than in the wastewaters surface(0.01-0.78 μg/mL) from the factories or closer areas around factories. Other species were not reaching the.criteria for lead determination.Conclusions:The Cx. quinquefasciatus larvae can bio-accumulate the metal and can potentially serve as a biomarker of lead contamination,to complemente conventional techniques.展开更多
文摘Objective Stagnant water in flower vases in a cemetery can become a breeding ground for mosquitoes,especially in warm and humid climates.The purpose of this survey is to determine whether the physical characteristics of the flower vases affect mosquito breeding.Methods The physical characteristics of a total of 527 flower vases and their impact on mosquito breeding were investigated in an old cemetery in Gainesville,Florida,during summers from 2000 to 2003,intermittently.Results The vases were categorized into five types based on their shape and material.Approximately 94.1%(496)of vases were made of stone,3.2%(17)were made of glass,1.9%(10)were made of metal,and 0.8%(4)were made of plastic or other materials.Approximately 44.6%(235/527)of the vases or containers were located in shady areas,most of which were under trees.Approximately 17.3%(91/527)of vases and containers held water,ranging from 100 mL to 1000 mL.About 48.4%(44/91)of the water-holding containers presented mosquito larvae.They were Aedes aegypti(5%),Aedes albopictus(60%),Aedes triseriatus(30%),Culex quinquefasciatus(2%),and Toxorhynchites.rutilus(2%).In addition,the prevention and management of mosquito breeding in cemetery flower vases have been proposed and discussed.Conclusions The physical characteristics of the flower vases impacted the container-inhabiting mosquitoes in the old urban cemetery.
文摘Objective:To identify the efficacy of Wolbachia-based intervention by reviewing community-based trials through meta-analysis and systematic review methods.Methods:Studies about Wolbachia-infected mosquito intervention were collected through a screening process.Records underwent data extraction and quality assessment independently by the authors.The primary outcome of the study was protective efficacy.Quantitative analysis was conducted through meta-analysis and multivariate meta-regression using Rstudio Ver.2024.09.0-375.Qualitative analysis was done by summarizing records’findings.Results:10 out of the 10660 records met the criteria.The evidence was moderate in quality and highly heterogeneous.Intervention consisted of releasing Wolbachia-infected Aedes aegypti in densely populated settlements.The combined protective efficacy of Wolbachia intervention against dengue is highly heterogeneous(79%;95%CI 70-88;I^(2)=98%).wMel strain is significantly more efficacious compared to wAlbB(protective efficacy 84%;95%CI 76-93;I^(2)=95%)vs.64%(95%CI 46-82;I^(2)=85%);P<0.01)in preventing dengue cases.Wolbachia-infected mosquito populations were found to be unstable upon release cessation,which necessitated periodic release and monitoring to maintain desired concentration and protective efficacy.Conclusions:Wolbachia-based intervention is effective in suppressing the transmission of mosquito-borne diseases,especially dengue,with an excellent safety profile.However,community acceptance and policy remain as significant barriers to implementation.
基金jointly funded by Campus France and China Scholarship Council through the PHC Cai Yuanpei 2016 program under grant number 36724VF(Laurent Dacheux)funding from Institut Pasteur,Parissupported by the MRC New Investigator Grant MR/Z506242/1.
文摘Dear Editor,Viruses transmitted by arthropods(arboviruses)are highly diverse,both genetically and in terms of host insect species.They are widely distributed across the virosphere,with significant representation in the family Rhabdoviridae,which encompasses a total of 580 different species divided into 4 sub-families and 62 genera(ICTV:https://talk.ictvonline.org/)(Kuhn et al.,2023;Walker et al.,2022).
文摘Background:This article examines the impact of the release of Wolbachia-infected population replacement mosquitoes as an innovative strategy for managing and controlling dengue in the Americas,using an approach based on the system dynamics methodology.The introduction of Wolbachia-carrying mosquitoes aims to reduce dengue transmission by interfering with the reproductive capacity of mosquitoes,thus limiting the spread of the virus.Objective:the objective of this study is to analyze how this intervention affects not only the incidence of dengue but also the health care system,evaluating changes in the demand for medical services and the costs associated with treatment in health care institutions.Specifically,it looks at the cost per visit to an Epidemiologist,a Family Doctor,diagnostic tests,and hospitalization.Methods:the study uses simulation scenarios to model the potential impact of the Wolbachia-based intervention in reducing dengue cases and its associated health and economic burden.The scenarios also assess the optimization of resources and improvements in the health system’s response to epidemic outbreaks.The simulation model utilizes real data from the Americas region to enhance the accuracy and relevance of the results.Conclusion:The results the potential of the release of Wolbachia-carrying mosquitoes to significantly mitigate the health and economic burden of dengue,with a maximum saving of 60.15%in the best simulation scenario.The approach not only highlights scientific innovation but also demonstrates its potential influence on public policy design.The findings support the implementation of sustainable strategies to maximize the benefits of this intervention and ensure its effective integration into public health programs,contributing to better long-term dengue management.
基金supported by the Deanship of Scientific Research,Vice Presidency for Graduate Studies and Scientific Research,King Faisal University,Saudi Arabia[Grant No.KFU252959].
文摘Malaria is a significant global health challenge.This devastating disease continues to affect millions,especially in tropical regions.It is caused by Plasmodium parasites transmitted by female Anopheles mosquitoes.This study introduces a nonlinear mathematical model for examining the transmission dynamics of malaria,incorporating both human and mosquito populations.We aim to identify the key factors driving the endemic spread of malaria,determine feasible solutions,and provide insights that lead to the development of effective prevention and management strategies.We derive the basic reproductive number employing the next-generation matrix approach and identify the disease-free and endemic equilibrium points.Stability analyses indicate that the disease-free equilibrium is locally and globally stable when the reproductive number is below one,whereas an endemic equilibrium persists when this threshold is exceeded.Sensitivity analysis identifies the most influential mosquito-related parameters,particularly the bite rate and mosquito mortality,in controlling the spread of malaria.Furthermore,we extend our model to include a treatment compartment and three disease-preventive control variables such as antimalaria drug treatments,use of larvicides,and the use of insecticide-treated mosquito nets for optimal control analysis.The results show that optimal use of mosquito nets,use of larvicides for mosquito population control,and treatment can lower the basic reproduction number and control malaria transmission with minimal intervention costs.The analysis of disease control strategies and findings offers valuable information for policymakers in designing cost-effective strategies to combat malaria.
基金supported by grants from the National Key Research and Development Program(2023YFE0113600).
文摘RNA interference(RNAi)is a post-transcriptional gene-silencing technique induced by the introduction of double-stranded RNA(dsRNA)or small interfering RNA(siRNA)[1].RNAi-based strategies have been extensively applied in the treatment of human diseases and crop protection against insect pests[2-4].With the availability of the full genome sequences of major mosquito vectors,RNAi has become increasingly used as a novel means of mosquito control[5].
文摘[Objective] The aim was to understand the species composition, distribution, density, seasonal fluctuation and pathogens of mosquitoes in four regions of East China to provide basic data for prevention and control of mosquitoes at ports. [Method] The mosquitoes at 21 ports of four regions in East China were investigated during 2011-2014 by CO2 lamp method, egg collection method, scoop method and visual method. The species of mosquitoes was identified, and pathogens in mosquitoes were detected. [Result] From 2011 to 2014, 102 583 mosquitoes were captured at the ports, belonging to 18 species, 6 genera and 1 family. Culex pipi- ens quinquefasciatus or Culex pipiens pallens was the dominant species at most ports. Mosquitoes could be captured from May to October, and the captured mosquitoes were the most in June. The positive rate of egg collectors was 9.41%, and the positive rate of breeding places was 7.23%. Rare entry mosquitoes were captured, and most of them were C. pipiens pallens. The detection results of dengue fever, malaria and other pathogens were negative. [Conclusion] C. pipiens quinquefasciatus or C. pipiens pallens was dominant at most ports, and the peak period was June. There were breeding environments of mosquitoes at some ports, so the prevention and control of mosquitoes at these ports should be paid more at- tention to in future.
文摘Variables among the macroclimate, microclimate and rice canopy categories and three other different farming systems were evaluated on their effects to the egg and larval density of Aedes spp. mosquitoes known as transmitters of animal and human diseases. No statistical difference in egg density (#eggs/mL) among farming systems (P = 0.345) were observed. However, there was significant difference in larval density (#1arvae/mL) among farming systems (P 〈 0.001) particularly between organic and conventional farms and between organic and mixed farms at (P 〈 0.05). Among the variables in the macroclimate category, wind velocity and ambient temperature significantly influenced larval density in conventional farms. Among the variables in the microclimate category, water temperature significantly contributed to larval density in both the mixed and conventional farms whereas water turbidity, in conventional farms. Among the variables in the rice canopy category, the number of tillers per plant was a significant contributor to larval density in all farm types. No variable among the environmental exposure categories affected the larval density in organic farms.
文摘Dengue fever is an acute infectious disease caused by the dengue virus and transmitted by mosquito vectors[1].Its clinical manifestations include high fever,headache,muscle and joint pain,and rash.It holds a significant position in global public health.In recent years,its incidence has continued to rise worldwide[2],making it one of the major diseases threatening human health.The disease course of dengue fever is divided into three typical phases:the acute febrile phase,the critical phase,and the recovery phase.While most patients experience mild symptoms,some may progress to severe dengue and potentially fatal outcomes if not promptly and effectively treated during the critical phase.
文摘[Objective] The study aimed to solve the problem of morphological identi- fication difficulties and propose solutions for the identification of foreign mosquitoes that are difficult to identify. [Method] Based on the sequencing, alignment and anal- ysis of COl gene fragment, DNA barcode technology was used to identify 7 exotic mosquitoes, and the phylogenetic analysis was performed using MEGA6.0 and DNASTAR software. Then the morphological characteristics of the mosquitoes were reviewed. [Result[ These mosquitoes were Armigeres subalbatus, Culex gefidus, Anopheles gambiae, and Culiseta incidens. [Conclusion] DNA barcode technology is a useful supplement to the morphological classification method of mosquitoes.
基金supported by the National Natural Science Foundation of China (No.10672035,No.90816025,No.10721062)SRFDP (No.20060141007)
文摘Mosquitoes are exceptional in their ability to pierce into human skin with a natural ultimate painless microneedle, named fascicle. Here the structure of the Aedes albopictus mosquito fascicle is obtained using a Scanning Electron Microscope (SEM), and the whole process of the fascicle inserting into human skin is observed using a high-speed video imaging technique. Direct measurements of the insertion force for mosquito fascicle to penetrate into human skin are reported. Results show that the mosquito uses a very low force (average 18 μN) to penetrate into the skin. This force is at least three orders of magnitude smaller than the reported lowest insertion force for an artificial microneedle with an ultra sharp tip to insert into the human skin. In order to understand the piercing mechanism of mosquito fascicle tip into human multilayer skin tissue, a numerical simulation is conducted to analyze the insertion process using a nonlinear finite element method. A good agreement occurs between the numerical results and the experimental measurements.
文摘Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefasciatus(Cx.quinquefasciatus) and Aedes albopictus(Ae.albopictus) in India.Methods:The R.communis seed extract was tested,employing WHO procedure,against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations(2-64μg/mL):the 24 h LC<sub>50</sub> values of the R.communis seed extract were determined following Probit analysis.The larval killing,antipupation and adult emergence inhibition rates of the test extract,using a single concentration of 2μLC<sub>50</sub>,were studied at different time periods(24-72 h):the extract toxicity was tested against a fish.Oreochromis niloticus(O.niloticus).Results:The R.communis seed extract exhibited larvicidal effects with 100%killing activities at concentrations 32-64μg/mL,and with LC<sub>50</sub> values 7.10.11.64 and 16.84μg/mL for Cx.quinquefasciatus,An.stephensi and Ae.albopictus larvae,respectively. When the larvae were treated with the extract at a single concentration of 2×LC<sub>50</sub>,significant differences were observed,compared to control groups,in rate of pupation(P【0.001) as well as in adult formation(P【0.001).Conclusions:The present findings suggest that the R.communis seed extract provided an excellent potential for controlling An.stephensi,Cx.quinquefasciatus and Ae. albopictus mosquito vectors.
文摘Objective:To determine the mosquito larvicidal activity of leaf essential oil and their chemical constituents from Clausena anisata(C.anisata)(Willd.) Hook.f.ex Benth.against Culex quinquefasciatus,Aedes aegypti and Anopheles Stephensi.Methods:Essential oil was obtained by hydro-distillation and the chemical composition of the leaf essential oil was analyzed using gas chromatography—mass spectrometry.The mosquitoes were reared in the vector control laboratory and twenty lateⅢinstar larvae of three mosquito species were exposed to based on the wide range and narrow range tests,essential oil was tested at 50.100.150,200 and 250 ppm and each compound was tested at various concentration(5-75 ppm) and were assayed in the laboratory by using the protocol of WHO 2005:the 24 h LC<sub>50</sub> values of the C.anisata leaf essential oil and their major compounds were determined following Probit analysis.Results:The oil contained were mainlyβ-pinene(32.8%),sabinene(28.3%),germacrene-D(12.7%),estragole (6.4%) and linalool(5.9%).The essential oil from the leaves of C.anisata exhibited significant larvicidal activity,with 24 h LC<sub>50</sub> values of 140.96,130.19 and 119.59 ppm.respectively.The five pure constituents extracted from the C.anisata leaf essential oil were also tested individually against three mosquito larvae.The LC<sub>50</sub> values ofβ-pinene,sabinene,germacrene-D,estragole and linalool appeared to be most effective against Anopheles stephensi(LC<sub>50</sub>-23.17,19.67,16.95. 11.01,35.17 ppm) followed by Aedes aegypti(LC<sub>50</sub>-27.69,21.20,18.76,12.70,38.64 ppm) and Culex quinquefasciatus(LC<sub>50</sub>-32.23,25.01.21.28,14.01,42.28).Conclusions:The essential oil of C. anisata contains five major compounds and has remarkable larvicidal properties,which may be considered as a potent source for the production of natural larvicides.
文摘Objective:To determine the larvicidal and repellent activities of Sida acuta Burm.F.(Family: Malvaceae)extract against Culex quinquefasciatus,Aedes aegypti and Anopheles stephensi. Methods:Twenty five late III instar larve of three mosquito species were exposed to various concentrations(15-90 mg/L) and were assayed in the laboratory by using the protocol of WHO 2005:the 24 h LC<sub>50</sub> values of the Sida acuta leaf extract was determined following Probit analysis. The repellent efficacy was determined against three mosquito species at three concentrations viz.,1.0,2.5 and 5.0 mg/cm<sup>2</sup> under the laboratory conditions.Results:Results showed varying degree of larvicidal activity of crude extract of Sida acuta against three important mosquitoes with LC<sub>50</sub> values ranging between 38 to 48 mg/L.The crude extract had strong repellent action against three species of mosquitoes as it provided 100%protection against Anopheles stephensi for 180 min followed by Aedes aegypti(150 min) and Culex quinquefasciatus(120 min).Conclusions: From the results it can be concluded the crude extract of Sida acuta was an excellent potential for controlling Culex quinquefasciatus,Aedes aegypti and Anopleles stephensi mosquitoes.
文摘Objective:To determine lead level primarily in Culex quinquefasciatus(Cx.quinquefasciatus), and Culex gelidus(Cx.gelidus) larvae inhabiting lead consuming factories,and to putatively estimate eco-toxicological impact of effluents from the firms.Methods:Third instars larvae were sampled by standard dipping method and lead concentrations in the larvae and their respective surrounding factory aquatic environments were determined through standard atomic absorption spectrophotometry(AAS).Results:Cx.quinquefasciatus was the most abundant species followed by Cx.gelidus.The levels of lead were higher in the Cx.quinquefasciatus(1.08-47.47μg/g),than in the wastewaters surface(0.01-0.78 μg/mL) from the factories or closer areas around factories. Other species were not reaching the.criteria for lead determination.Conclusions:The Cx. quinquefasciatus larvae can bio-accumulate the metal and can potentially serve as a biomarker of lead contamination,to complemente conventional techniques.