1
|
Vivekanandhan P, Alharbi SA, Ansari MJ. Toxicity, biochemical and molecular docking studies of Acacia nilotica L., essential oils against insect pests. Toxicon 2024; 243:107737. [PMID: 38677379 DOI: 10.1016/j.toxicon.2024.107737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/22/2024] [Accepted: 04/22/2024] [Indexed: 04/29/2024]
Abstract
Botanical essential oils are natural insecticides derived from plants, offering eco-friendly alternatives to synthetic chemicals for pest control. In this study, the essential oils were extracted from Acacia nilotica seed cotyledons, and their toxicity was tested against insect pests. Furthermore, the chemical components of the essential oils were identified through gas chromatography-mass spectrometry (GC-MS) analysis. The essential oil extracted from A. nilotica seeds exhibited the highest mortality rates of 60% and 98% in Culex quinquefasciatus, and 60% and 96.66% mortality in Plutella xylostella at 24 and 48 h after treatment, respectively. The essential oils resulted in a lower LC50 of 159.263 ppm/mL, and LC90 of 320.930 ppm/mL within 24 h. In 48 h, the LC50 was 52.070 ppm/mL and the LC90 was 195.123 ppm/mL for C. quinquefasciatus. In the essential oil treatment of P. xylostella, the lower LC50 was 165.900 ppm/mL, and the LC90 was 343.840 ppm/mL 24 h after the treatment. At 48 h post-treatment, the LC50 decreased to 62.965 ppm/mL, and the LC90 decreased to 236.795 ppm/mL in P. xylostella. The study investigated the impact of essential oils on insect enzymes 24 h after treatment. The study revealed significant changes in the levels of insect enzymes, including a decrease in acetylcholinesterase enzymes and an increase in glutathione S-transferase compared to the control group. Essential oils had minimal effects, resulting in mortality rates of 30.66% and 46% at 24 and 48 h after treatment on Artemia salina. After 48 h, minimal toxic effects of essential oils were observed on E. eugeniae, with a mortality rate of 11.33%. The GC-MS analysis of A. nilotica seed-derived essential oils revealed ten major chemical constituents, including 6-hydroxymellein, phthalic acid, trichloroacetic acid, hexadecane, acetamide, heptacosane, eicosane, pentadecane, 1,3,4-eugenol, and chrodrimanin B. Among these constituents, Heptacosane is the major chemical component, and this molecule has a high potential for involvement in insecticidal activity.
Collapse
Affiliation(s)
- Perumal Vivekanandhan
- Department of General Pathology, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, 600077, India.
| | - Sulaiman Ali Alharbi
- Department of Botany & Microbiology College of Science King Saud University, P.O Box 2455, Riyadh, 11451, Saudi Arabia
| | - Mohammad Javed Ansari
- Department of Botany, Hindu College Moradabad (Mahatma Jyotiba Phule Rohilkhand University Bareilly), India
| |
Collapse
|
2
|
Patel K, Akbari D, Pandya RV, Trivedi J, Mevada V, Wanale SG, Patel R, Yadav VK, Tank JG, Sahoo DK, Patel A. Larvicidal proficiency of volatile compounds present in Commiphora wightii gum extract against Aedes aegypti (Linnaeus, 1762). FRONTIERS IN PLANT SCIENCE 2023; 14:1220339. [PMID: 37711311 PMCID: PMC10499046 DOI: 10.3389/fpls.2023.1220339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 08/07/2023] [Indexed: 09/16/2023]
Abstract
Aedes mosquitoes are the major cause of several vector-borne diseases in tropical and subtropical regions. Synthetic pesticides against these mosquitoes have certain limitations; hence, natural, eco-friendly, and safe larvicides obtained from plant resources are used to overcome these. In the present study, the larvicidal efficiency of Commiphora wightii against the fourth instar stage of the dengue fever mosquito Aedes aegypti (Linnaeus, 1762) was studied. The gum resin of C. wightii was collected using the borehole tapping method, and hexane extracts in different concentrations were prepared. The fourth-instar larvae were exposed to the extracts, and percent mortality, as well as LC20, LC50, and LC90, was calculated. Volatile compounds of the hexane gum extract were analyzed by Headspace GC/MS, and the sequence of the acetylcholine, Gamma-aminobutyric acid (GABA) receptor, and octopamine receptor subunit of A. aegypti was obtained. It was found that the hexane gum extract was toxic and lethal for larvae at different concentrations. Minimum mortality was observed at 164 µg mL-1 (10%/h), while maximum mortality was at 276 µg mL-1 (50%/h). The lethal concentrations LC20, LC50, and LC90 were 197.38 µg mL-1, 294.13 µg mL-1, and 540.15 µg mL-1, respectively. The GC/MS analysis confirmed the presence of diterpenes, monoterpenes, monoterpene alcohol, and sesquiterpenes in the gum samples, which are lethal for larvae due to their inhibitory activity on the acetylcholinesterase enzyme, GABA receptor, and octopamine receptor subunit. The use of commonly occurring plant gum for the control of mosquitoes was explored, and it was found that the gum of C. wightii had larvicidal activities and could be potentially insecticidal.
Collapse
Affiliation(s)
- Krupal Patel
- Marine Biodiversity and Ecology Laboratory, Department of Zoology, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat, India
| | - Divya Akbari
- University Grants Commission-Career Advancement Scheme (UGC-CAS) Department of Biosciences, Saurashtra University, Rajkot, Gujarat, India
| | - Rohan V. Pandya
- Department of Microbiology, Atmiya University, Rajkot, Gujarat, India
| | - Jigneshkumar Trivedi
- Department of Life Sciences, Hemchandracharya North Gujarat University, Patan, Gujarat, India
| | - Vishal Mevada
- DNA Division, Directorate of Forensic Science, Gandhinagar, India
| | - Shivraj Gangadhar Wanale
- School of Chemical Sciences, Swami Ramanand Teerth Marathwada University, Nanded, Maharashtra, India
| | - Rajesh Patel
- Department of Biosciences, Veer Narmad South Gujarat University, Surat, India
| | - Virendra Kumar Yadav
- Department of Life Sciences, Hemchandracharya North Gujarat University, Patan, Gujarat, India
| | - Jigna G. Tank
- University Grants Commission-Career Advancement Scheme (UGC-CAS) Department of Biosciences, Saurashtra University, Rajkot, Gujarat, India
| | - Dipak Kumar Sahoo
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Ashish Patel
- Department of Life Sciences, Hemchandracharya North Gujarat University, Patan, Gujarat, India
| |
Collapse
|
3
|
Subedi D, Subedi S, Acharya KP, Sah R. No room for complacency to control dengue in Nepal. QJM 2023; 116:591-593. [PMID: 36448704 DOI: 10.1093/qjmed/hcac263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 12/05/2022] Open
Affiliation(s)
- D Subedi
- From the Department of Veterinary Science and Animal Husbandry, Paklihawa Campus, Institute of Agriculture and Animal Science, Tribhuvan University, Rupandehi, Nepal
- Department of Poultry Science, University of Georgia, Athens, GA, USA
| | - S Subedi
- Department of Community Medicine, School of Public Health, Chitwan Medical College, Chitwan, Nepal
| | - K P Acharya
- Animal Quarantine Office-Kathmandu, Department of Livestock Services (DLS), Budhanilkantha, Kathmandu, Nepal
| | - R Sah
- Department of Microbiology, Tribhuvan University Teaching Hospital, Institute of Medicine, Kathmandu, Nepal
- Department of Microbiology, Dr. D.Y. Patil Medical College, Hospital and Research Centre, Dr. D.Y. Patil Vidyapeeth, Pune, Maharashtra, India
- Department of Global Health and Clinical Research, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
4
|
Liu Q, Wang J, Hou J, Wu Y, Zhang H, Xing D, Gao J, Li C, Guo X, Jiang Y, Gong Z, Zhao T. Entomological Investigation and Detection of Dengue Virus Type 1 in Aedes (Stegomyia) albopictus (Skuse) During the 2018–2020 Outbreak in Zhejiang Province, China. Front Cell Infect Microbiol 2022; 12:834766. [PMID: 35846756 PMCID: PMC9283783 DOI: 10.3389/fcimb.2022.834766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 05/31/2022] [Indexed: 11/13/2022] Open
Abstract
Mosquito-borne diseases are still threats to public health in the Zhejiang province of China. Surveillance of mosquitoes and the mosquito-borne pathogen is a vital approach for early warning, prevention, and control of the infectious disease. In this study, from 2018 to 2020, a total of 141607 female mosquitoes were caught by means of the light trap method. The main species were Culex pipiens quinquefasciatus/pallens (41.32%), Culex tritaeniorhynchus (47.6%), Aedes albopictus (2.5%), Anopheles sinensis (5.87%), Armigeres subalbatus (2.64%) and other mosquito species (0.07%). Cx. pipiens s.l. were the dominant species in two urban habitats and rural residential areas while Cx. tritaeniorhynchus was the main dominant species in the rural livestock sheds. In terms of seasonal fluctuation, Cx. pipiens s.l fluctuated at a high level from May to October. The peaks of Cx. tritaeniorhynchus, An. sinensis and Ar. subalbatus were in July. In addition, a total of 693 Ae. albopictus were collected with Biogents Mosquitaire CO2 traps in emergency surveillance of dengue fever (DF) and screened for dengue virus infection. There were three circumstances of collection: The first: the sampling time before mosquito control during the local outbreak of DF in Lucheng of Wenzhou, 2019; The second circumstance: the sampling time after mosquito control during the local outbreak of DF of other cities in 2018-2019; The third circumstance: past DF epidemic areas the sampling time before mosquito control during the local outbreak of DF in Lucheng, Wenzhou, Zhejiang, 2019. The pools formed by mosquitoes collected in these three circumstances were 3 (6.1%), 35 (71.5%), and 11 (22.4%) respectively. Of the 49 pools tested, only one in the first circumstance was positive. The full-length dengue virus sequence of ZJWZ/2019 was obtained by sequencing and uploaded to the NCBI as number OK448162. Full-length nucleotide and amino acid homology analyses showed that ZJWZ2019 and Wenzhou DF serum isolates ZJWZ-62/2019 (MW582816) and ZJWZ-18/2019 (MW582815) had the highest homology. The analysis of full genome and E gene phylogenetic trees showed that ZJWZ2019 belonged to serotype 1, genotype I, lineage II, which was evolutionarily related to OK159963/Cambodia/2019. It implies that ZJWZ2019 originated in Cambodia. This study showed the species composition, seasonal dynamics of mosquitoes in different habitats in Zhejiang province and confirmed the role of Ae. albopictus in the transmission cycle of in outbreak of DF in the Lucheng district of Wenzhou in 2019, suggesting the importance of monitoring of vector Aedes infected dengue virus in the prevention and control of DF.
Collapse
Affiliation(s)
- Qinmei Liu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
- Department of Infectious Diseases Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Jinna Wang
- Department of Infectious Diseases Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Juan Hou
- Department of Infectious Diseases Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Yuyan Wu
- Department of Infectious Diseases Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Hengduan Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
| | - Dan Xing
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
| | - Jian Gao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
| | - Chunxiao Li
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
| | - Xiaoxia Guo
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
| | - Yuting Jiang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
| | - Zhenyu Gong
- Department of Infectious Diseases Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
- *Correspondence: Zhenyu Gong, ; Tongyan Zhao,
| | - Tongyan Zhao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector-Borne and Natural Focus Infectious Diseases, Institute of Microbiology and Epidemiology, Beijing, China
- *Correspondence: Zhenyu Gong, ; Tongyan Zhao,
| |
Collapse
|
5
|
Roy J. The synthesis and applications of TiO2 nanoparticles derived from phytochemical sources. J IND ENG CHEM 2022. [DOI: 10.1016/j.jiec.2021.10.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
6
|
Virome in adult Aedes albopictus captured during different seasons in Guangzhou City, China. Parasit Vectors 2021; 14:415. [PMID: 34407871 PMCID: PMC8371599 DOI: 10.1186/s13071-021-04922-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 08/03/2021] [Indexed: 01/09/2023] Open
Abstract
Background The mosquito Aedes albopictus is an important vector for many pathogens. Understanding the virome in Ae. albopictus is critical for assessing the risk of disease transmission, implementation of vector control measures, and health system strengthening. Methods In this study, viral metagenomic and PCR methods were used to reveal the virome in adult Ae. albopictus captured in different areas and during different seasons in Guangzhou, China. Results The viral composition of adult Ae. albopictus varied mainly between seasons. Over 50 viral families were found, which were specific to vertebrates, invertebrates, plants, fungi, bacteria, and protozoa. In rural areas, Siphoviridae (6.5%) was the most common viral family harbored by mosquitoes captured during winter and spring, while Luteoviridae (1.1%) was the most common viral family harbored by mosquitoes captured during summer and autumn. Myoviridae (7.0% and 1.3%) was the most common viral family in mosquitoes captured in urban areas during all seasons. Hepatitis B virus (HBV) was detected by PCR in a female mosquito pool. The first near full-length HBV genome from Ae. albopictus was amplified, which showed a high level of similarity with human HBV genotype B sequences. Human parechovirus (HPeV) was detected in male and female mosquito pools, and the sequences were clustered with HPeV 1 and 3 sequences. Conclusions Large numbers of viral species were found in adult Ae. albopictus, including viruses from vertebrates, insects, and plants. The viral composition in Ae. albopictus mainly varied between seasons. Herein, we are the first to report the detection of HPeV and HBV in mosquitoes. This study not only provides valuable information for the control and prevention of mosquito-borne diseases, but it also demonstrates the feasibility of xenosurveillance. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-04922-z.
Collapse
|
7
|
Guo C, Lin J, Chen W, Zhang Z, Wu D, Ke C. Molecular Epidemiology of Dengue Viruses Isolated in Shantou City, China, during 2015–2017. Jpn J Infect Dis 2020; 73:300-305. [DOI: 10.7883/yoken.jjid.2019.435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Chuan Guo
- Center for Disease Control and Prevention of Shantou city, Shantou city, Guangdong, China
| | - Jiemin Lin
- Center for Disease Control and Prevention of Shantou city, Shantou city, Guangdong, China
| | - Wan Chen
- Center for Disease Control and Prevention of Shantou city, Shantou city, Guangdong, China
| | - Zhihua Zhang
- Center for Disease Control and Prevention of Shantou city, Shantou city, Guangdong, China
| | - De Wu
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou city, Guangdong, China
| | - Changwen Ke
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou city, Guangdong, China
| |
Collapse
|
8
|
Kuczera D, Assolini JP, Tomiotto-Pellissier F, Pavanelli WR, Silveira GF. Highlights for Dengue Immunopathogenesis: Antibody-Dependent Enhancement, Cytokine Storm, and Beyond. J Interferon Cytokine Res 2019; 38:69-80. [PMID: 29443656 DOI: 10.1089/jir.2017.0037] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Infection with dengue virus (DENV) can lead to a wide spectrum of clinical presentations, ranging from asymptomatic infection to death. It is estimated that the disease manifests only in 90 million cases out of the total 390 million yearly infections. Even though research has not yet elucidated which are the precise pathophysiological mechanisms that trigger severe forms of dengue, the infection elicits a critical immune response significant for dengue pathogenesis development. Understanding how the immune response to DENV is established and how it can resolve the infection or turn into an immunopathology is of great importance in DENV research. Currently, studies have extensively debated 2 hypotheses involving immune response: antibody-dependent enhancement and cytokine storm. However, despite its undeniable importance in severe forms of the disease, these 2 hypotheses are based on a primed immune status resulting from previous heterologous infection, abstaining them from explaining the severe forms of dengue in naive immune subjects, for example. Thus, it seems that a more intricate arrangement of causes and conditions must be achieved to severe dengue to occur. Among them, the cytokine network signature elicited, in association with viral aspects deserves special attention regarding the establishment of infection and evolution to pathogenesis. In this work, we intend to shed light on how those elements contribute to severe dengue development.
Collapse
Affiliation(s)
- Diogo Kuczera
- 1 Laboratório de Virologia Molecular, Instituto Carlos Chagas , ICC/Fiocruz/PR, Curitiba, Brazil
| | - João Paulo Assolini
- 2 Departamento de Ciências Patológicas, Centro de Ciências Biológicas , Universidade Estadual de Londrina, Londrina, Brazil
| | - Fernanda Tomiotto-Pellissier
- 2 Departamento de Ciências Patológicas, Centro de Ciências Biológicas , Universidade Estadual de Londrina, Londrina, Brazil
| | - Wander Rogério Pavanelli
- 2 Departamento de Ciências Patológicas, Centro de Ciências Biológicas , Universidade Estadual de Londrina, Londrina, Brazil
| | | |
Collapse
|
9
|
Lai YH. The climatic factors affecting dengue fever outbreaks in southern Taiwan: an application of symbolic data analysis. Biomed Eng Online 2018; 17:148. [PMID: 30396346 PMCID: PMC6218984 DOI: 10.1186/s12938-018-0575-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dengue fever is a leading cause of severe illness and hospitalization in Taiwan. This study sought to elucidate the linkage between dengue fever incidence and climate factors. RESULTS The result indicated that temperature, accumulated rainfall, and sunshine play an important role in the transmission cycles of dengue fever. A predictive model equation plots dengue fever incidence versus temperature, rainfall, and sunshine, and it suggests that temperature, rainfall, and sunshine are significantly correlated with dengue fever incidence. CONCLUSIONS The data suggests that climate factors are important determinants of dengue fever in southern Taiwan. Dengue fever viruses and the mosquito vectors are sensitive to their environment. Temperature, rainfall and sunshine have well-defined roles in the transmission cycle. This finding suggests that control of mosquito by climatic factor during high temperature seasons may be an important strategy for containing the burden of dengue fever.
Collapse
Affiliation(s)
- Yi-Horng Lai
- Department of Health Care Administration, Oriental Institute of Technology, No. 58, Sec. 2, Sichuan Rd., Banqiao Dist., New Taipei City, 22061, Taiwan.
| |
Collapse
|
10
|
Eder M, Cortes F, Teixeira de Siqueira Filha N, Araújo de França GV, Degroote S, Braga C, Ridde V, Turchi Martelli CM. Scoping review on vector-borne diseases in urban areas: transmission dynamics, vectorial capacity and co-infection. Infect Dis Poverty 2018; 7:90. [PMID: 30173661 PMCID: PMC6120094 DOI: 10.1186/s40249-018-0475-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 08/02/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Transmission dynamics, vectorial capacity, and co-infections have substantial impacts on vector-borne diseases (VBDs) affecting urban and suburban populations. Reviewing key factors can provide insight into priority research areas and offer suggestions for potential interventions. MAIN BODY Through a scoping review, we identify knowledge gaps on transmission dynamics, vectorial capacity, and co-infections regarding VBDs in urban areas. Peer-reviewed and grey literature published between 2000 and 2016 was searched. We screened abstracts and full texts to select studies. Using an extraction grid, we retrieved general data, results, lessons learned and recommendations, future research avenues, and practice implications. We classified studies by VBD and country/continent and identified relevant knowledge gaps. Of 773 articles selected for full-text screening, 50 were included in the review: 23 based on research in the Americas, 15 in Asia, 10 in Africa, and one each in Europe and Australia. The largest body of evidence concerning VBD epidemiology in urban areas concerned dengue and malaria. Other arboviruses covered included chikungunya and West Nile virus, other parasitic diseases such as leishmaniasis and trypanosomiasis, and bacterial rickettsiosis and plague. Most articles retrieved in our review combined transmission dynamics and vectorial capacity; only two combined transmission dynamics and co-infection. The review identified significant knowledge gaps on the role of asymptomatic individuals, the effects of co-infection and other host factors, and the impacts of climatic, environmental, and socioeconomic factors on VBD transmission in urban areas. Limitations included the trade-off from narrowing the search strategy (missing out on classical modelling studies), a lack of studies on co-infections, most studies being only descriptive, and few offering concrete public health recommendations. More research is needed on transmission risk in homes and workplaces, given increasingly dynamic and mobile populations. The lack of studies on co-infection hampers monitoring of infections transmitted by the same vector. CONCLUSIONS Strengthening VBD surveillance and control, particularly in asymptomatic cases and mobile populations, as well as using early warning tools to predict increasing transmission, were key strategies identified for public health policy and practice.
Collapse
Affiliation(s)
- Marcus Eder
- Public Health England Sierra Leone Country Office, Freetown, Sierra Leone
- Aggeu Magalhaes Institute (IAM) / Oswaldo Cruz Foundation (Fiocruz), Avenida Professor Moraes Rego, s/n. Cidade Universitaria. CEP 50, Recife, Pernambuco 740-465 Brazil
| | - Fanny Cortes
- Universidade de Pernambuco (UPE), Recife, Pernambuco Brazil
| | | | | | - Stéphanie Degroote
- University of Montreal School of Public Health (ESPUM), Montreal, Quebec Canada
| | - Cynthia Braga
- Aggeu Magalhaes Institute (IAM) / Oswaldo Cruz Foundation (Fiocruz), Avenida Professor Moraes Rego, s/n. Cidade Universitaria. CEP 50, Recife, Pernambuco 740-465 Brazil
| | - Valéry Ridde
- University of Montreal School of Public Health (ESPUM), Montreal, Quebec Canada
- IRD (French Institute For Research on Sustainable Development), CEPED (IRD-Université Paris Descartes), Universités Paris Sorbonne Cités, ERL INSERM SAGESUD, Paris, France
| | - Celina Maria Turchi Martelli
- Aggeu Magalhaes Institute (IAM) / Oswaldo Cruz Foundation (Fiocruz), Avenida Professor Moraes Rego, s/n. Cidade Universitaria. CEP 50, Recife, Pernambuco 740-465 Brazil
| |
Collapse
|
11
|
Yan H, Ding Z, Yan J, Yao W, Pan J, Yang Z, Lou X, Mao H, Lin J, Sun J, Hou J, Wu H, Wu C, Zhang Y. Epidemiological Characterization of the 2017 Dengue Outbreak in Zhejiang, China and Molecular Characterization of the Viruses. Front Cell Infect Microbiol 2018; 8:216. [PMID: 30023351 PMCID: PMC6039557 DOI: 10.3389/fcimb.2018.00216] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 06/07/2018] [Indexed: 11/24/2022] Open
Abstract
Dengue, a mosquito-borne disease caused by the dengue virus (DV), has been recognized as a global public health threat. In 2017, an unexpected dengue outbreak occurred in Zhejiang, China. To clarify and characterize the causative agent of this outbreak, data on dengue fever cases were collected from the China Information System for Disease Control and Prevention in Zhejiang province for subsequent epidemiological analysis. A total of 1,229 cases were reported, including 1,149 indigenous and 80 imported cases. Most indigenous cases (1,128 cases) were in Hangzhou. The epidemic peak occurred in late August and early September, and the incidence rate of elderly people (4.34 per 100,000) was relatively high. Imported cases were reported all year round, and most were from South-East Asia and Western Pacific regions. Young people and men accounted for a large fraction of the cases. Acute phase serums of patients were collected for virus isolation. And 35 isolates (including 25 DV-2, 8 DV-1, 1 DV-3, and 1 DV-4) were obtained after inoculation and culture in mosquito C6/36 cells. The E genes of the 35 new DV isolates and the complete genome of a DV-2 isolate (Zhejiang/HZ33/2017), and the E gene of a DV-2 isolate from Ae. albopictus (Zhejiang/Aedes-1/2017) were determined. Phylogenetic analyses were performed using the neighbor-joining method with the Tajima-Nei model. Phylogenetically, DVs of all four serotypes with multiple genotypes (mainly including 21 Cosmopolitan genotype DV-2, 4 Asian I genotype DV-2, 6 genotype I DV-1, and 2 genotype V DV-1) were present in the indigenous and imported cases in Zhejiang during the same period. Most of the isolates probably originated from South-East Asia and Western Pacific countries. The imported cases, high density of mosquito vector, and missed diagnosis might contribute to the 2017 outbreak in Zhejiang.
Collapse
Affiliation(s)
- Hao Yan
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Zheyuan Ding
- Department of Public Health Surveillance and Advisory, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Juying Yan
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Wenwu Yao
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Junhang Pan
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Zhangnv Yang
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Xiuyu Lou
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Haiyan Mao
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Junfen Lin
- Department of Public Health Surveillance and Advisory, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Jimin Sun
- Department of Communicable Disease Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Juan Hou
- Department of Communicable Disease Control and Prevention, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Haocheng Wu
- Department of Public Health Surveillance and Advisory, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Chen Wu
- Department of Public Health Surveillance and Advisory, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| | - Yanjun Zhang
- Department of Microbiology, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, China
| |
Collapse
|
12
|
Li C, Lu Y, Liu J, Wu X. Climate change and dengue fever transmission in China: Evidences and challenges. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 622-623:493-501. [PMID: 29220773 DOI: 10.1016/j.scitotenv.2017.11.326] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/28/2017] [Accepted: 11/28/2017] [Indexed: 06/07/2023]
Abstract
Dengue Fever (DF) has become one of the most serious infectious diseases in China. Dengue virus and its vector (Aedes mosquito) are known to be sensitive to climate condition. Climate impacts DF through affecting three essential bioecological aspects: DF virus, vector (mosquito) and DF transmission environment. Weather-based DF model, mosquito model and climate model are the three pillars to help the prediction of DF distribution. Through a systematic review of literature between 1980 and 2017, this paper summarizes empirical evidences in China on the impact of climate change on DF; it further reviews the related DF incidence models and their findings on how changes in weather factors may impact DF occurrences in China. Compared with some well-known research projects in the western countries, there is a lack of knowledge in China regarding how the spatiotemporal distribution of DF will respond to climate change. However, being able to predict DF distribution is key to China's efforts to prevent and control DF transmission. We conclude this paper by recommending four focused areas for China: promoting more advanced research on the relationship between extreme weather events and DF, developing regional-specific models for the high risk regions of DF in south China, encouraging interdisciplinary collaboration between climate studies and health services, and enhancing public health education and management at national, regional and local levels.
Collapse
Affiliation(s)
- Chenlu Li
- College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China
| | - Yongmei Lu
- Department of Geography, Texas State University, San Marcos, TX 78666-4684, USA.
| | - Jianing Liu
- College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China
| | - Xiaoxu Wu
- College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China.
| |
Collapse
|
13
|
Vivekanandhan P, Venkatesan R, Ramkumar G, Karthi S, Senthil-Nathan S, Shivakumar MS. Comparative Analysis of Major Mosquito Vectors Response to Seed-Derived Essential Oil and Seed Pod-Derived Extract from Acacia nilotica. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2018; 15:ijerph15020388. [PMID: 29473901 PMCID: PMC5858457 DOI: 10.3390/ijerph15020388] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 11/16/2022]
Abstract
Botanical metabolites are increasingly realized as potential replacements to chemical insecticides. In the present study, Acacia nilotica seed essential oil and seed pod solvent extracts were tested for bioefficacy against three important types of mosquitoes. Mortality was recorded 24 h post-treatment, while smoke toxicity of adult mosquitoes was recorded at 10 min intervals for 40 min. Seed pod powder was extracted with different solvents and hydrodistilled seed oil chemical constituents were determined by using Gas chromatography mass spectroscopy (GC-MS) -. Larvicidal and adulticidal efficacy of seed hydrodistilled essential oil and solvent extracts were tested against larval and adult mosquitoes. The seed hydrodistilled oil provided strong larvicidal activity against Anopheles stephensi, (LC50 (lethal concentration that kills 50% of the exposed larvae) = 5.239, LC90 (lethal concentration that kills 90% of the exposed larvae) = 9.713 mg/L); Aedes aegypti, (LC50 = 3.174, LC90 = 11.739 mg/L); and Culex quinquefasciatus, (LC50 = 4.112, LC90 = 12.325 mg/L). Smoke toxicities were 82% in Cx. quinquefasciatus, 90% in Ae. aegypti, and 80% mortality in An. stephensi adults, whereas 100% mortality was recorded for commercial mosquito coil. The GC-MS profile of seed essential oil from A. nilotica showed the presence of hexadecane (18.440%) and heptacosane (15.914%), which are the main and active compounds, and which may be involved in insecticidal activity. Overall findings suggest that the seed oil showed strong mosquitocidal activity against mosquito vectors and therefore may provide an ecofriendly replacement to chemical insecticides.
Collapse
Affiliation(s)
- Perumal Vivekanandhan
- Molecular Entomology Laboratory, Department of Biotechnology, School of Biosciences, Periyar University, Salem, Tamil Nadu 636 011, India.
| | - Raji Venkatesan
- Molecular Entomology Laboratory, Department of Biotechnology, School of Biosciences, Periyar University, Salem, Tamil Nadu 636 011, India.
| | - Govindaraju Ramkumar
- Molecular Entomology Laboratory, Department of Biotechnology, School of Biosciences, Periyar University, Salem, Tamil Nadu 636 011, India.
| | - Sengodan Karthi
- Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu 627 412, India.
| | - Sengottayan Senthil-Nathan
- Division of Biopesticides and Environmental Toxicology, Sri Paramakalyani Centre for Excellence in Environmental Sciences, Manonmaniam Sundaranar University, Alwarkurichi, Tirunelveli, Tamil Nadu 627 412, India.
| | | |
Collapse
|
14
|
Kovendan K, Chandramohan B, Govindarajan M, Jebanesan A, Kamalakannan S, Vincent S, Benelli G. Orchids as Sources of Novel Nanoinsecticides? Efficacy of Bacillus sphaericus and Zeuxine gracilis-Fabricated Silver Nanoparticles Against Dengue, Malaria and Filariasis Mosquito Vectors. J CLUST SCI 2018. [DOI: 10.1007/s10876-018-1331-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
15
|
Udayabhanu J, Kannan V, Tiwari M, Natesan G, Giovanni B, Perumal V. Nanotitania crystals induced efficient photocatalytic color degradation, antimicrobial and larvicidal activity. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 178:496-504. [DOI: 10.1016/j.jphotobiol.2017.12.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/03/2017] [Accepted: 12/04/2017] [Indexed: 11/26/2022]
|
16
|
Wei K, Li Y. Global evolutionary history and spatio-temporal dynamics of dengue virus type 2. Sci Rep 2017; 7:45505. [PMID: 28378782 PMCID: PMC5381229 DOI: 10.1038/srep45505] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 02/27/2017] [Indexed: 11/08/2022] Open
Abstract
DENV-2 spread throughout the tropical and subtropical regions globally, which is implicated in deadly outbreaks of DHF and DSS. Since dengue cases have grown dramatically in recent years, about half of the world's population is now at risk. Our timescale analysis indicated that the most recent common ancestor existed about 100 years ago. The rate of nucleotide substitution was estimated to be 8.94 × 10-4 subs/site/year. Selection pressure analysis showed that two sites 160 and 403 were under positive selection, while E gene is mainly shaped by stronger purifying selection. BSP analysis showed that estimating effective population size from samples of sequences has undergone three obvious increases, additionally, Caribbean and Puerto Rico maintained higher levels of genetic diversity relative to other 6 representative geographical populations using GMRF method. The phylogeographic analysis indicated that two major transmission routes are from South America to Caribbean and East&SouthAsia to Puerto Rico. The trunk reconstruction confirmed that the viral evolution spanned 50 years occurred primarily in Southeast Asia and East&South Asia. In addition, phylogeographic association-trait analysis indicated that the viral phenotypes are highly correlated with phylogeny in Nicaragua and Puerto Rico (P < 0.05).
Collapse
Affiliation(s)
- Kaifa Wei
- School of Biological Sciences and Biotechnology, Minnan Normal University, Zhangzhou 363000, China
| | - Yuhan Li
- School of Biological Sciences and Biotechnology, Minnan Normal University, Zhangzhou 363000, China
| |
Collapse
|
17
|
Li G, Pan P, He Q, Kong X, Wu K, Zhang W, Liu Y, Huang H, Liu J, Zhang Z, Wu D, Lai X, Liu X, Wu J. Molecular epidemiology demonstrates that imported and local strains circulated during the 2014 dengue outbreak in Guangzhou, China. Virol Sin 2017; 32:63-72. [PMID: 28120220 PMCID: PMC6702253 DOI: 10.1007/s12250-016-3872-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 11/15/2016] [Indexed: 11/28/2022] Open
Abstract
The dengue virus (DENV) is a vital global public health issue. The 2014 dengue
epidemic in Guangzhou, China, caused approximately 40,000 cases of infection and
five deaths. We carried out a comprehensive investigation aimed at identifying the
transmission sources in this dengue epidemic. To analyze the phylogenetics of the
2014 dengue strains, the envelope (E) gene
sequences from 17 viral strains isolated from 168 dengue patient serum samples were
sequenced and a phylogenetic tree was reconstructed. All 17 strains were serotype I
strains, including 8 genotype I and 9 genotype V strains. Additionally, 6 genotype I
strains that were probably introduced to China from Thailand before 2009 were widely
transmitted in the 2013 and 2014 epidemics, and they continued to circulate until
2015, with one affinis strain being found in Singapore. The other 2 genotype I
strains were introduced from the Malaya Peninsula in 2014. The transmission source
of the 9 genotype V strains was from Malaysia in 2014. DENVs of different serotypes
and genotypes co-circulated in the 2014 dengue outbreak in Guangzhou. Moreover, not
only had DENV been imported to Guangzhou, but it had also been gradually exported,
as the viruses exhibited an enzootic transmission cycle in Guangzhou. ![]()
Collapse
Affiliation(s)
- Geng Li
- School of Chinese Meterla Medica, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China.,State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Pan Pan
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Qiuyan He
- School of Chinese Meterla Medica, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Xiujuan Kong
- School of Chinese Meterla Medica, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Kailang Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Wei Zhang
- School of Chinese Meterla Medica, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China.,State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Yuntao Liu
- Guangdong Province Traditional Chinese Medical Hospital, Guangzhou, 510120, China
| | - Huiting Huang
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, China
| | - Jianbo Liu
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, China
| | - Zhongde Zhang
- Guangdong Province Traditional Chinese Medical Hospital, Guangzhou, 510120, China
| | - De Wu
- Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, 511430, China
| | - Xiaoping Lai
- School of Chinese Meterla Medica, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Xiaohong Liu
- School of Chinese Meterla Medica, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China.,The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510120, China
| | - Jianguo Wu
- School of Chinese Meterla Medica, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China. .,State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, 430072, China.
| |
Collapse
|
18
|
Ali ZA, Roslan MA, Yahya R, Wan Sulaiman WY, Puteh R. Eco‐friendly synthesis of silver nanoparticles and its larvicidal property against fourth instar larvae of
Aedes aegypti. IET Nanobiotechnol 2016; 11:152-156. [DOI: 10.1049/iet-nbt.2015.0123] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Zainal Abidin Ali
- Department of PhysicsFaculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia
| | - Muhammad Aidil Roslan
- Department of ParasitologyFaculty of MedicineUniversity of MalayaKuala Lumpur 50603Malaysia
| | - Rosiyah Yahya
- Department of ChemistryFaculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia
| | | | - Rustam Puteh
- Department of PhysicsFaculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia
| |
Collapse
|
19
|
Gorle S, Maddila S, Chokkakula S, Lavanya P, Singh M, Jonnalagadda SB. Synthesis, Biological Activity of Pyrimidine Linked with Morpholinophenyl Derivatives. J Heterocycl Chem 2015. [DOI: 10.1002/jhet.2498] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Sridevi Gorle
- Discipline of Biochemistry, School of Life Sciences; University of KwaZulu-Natal; Westville Campus, Chiltern Hills Durban 4000 South Africa
| | - Suresh Maddila
- School of Chemistry and Physics; University of KwaZulu-Natal; Westville Campus, Chilten Hills, Private Bag 54001 Durban 4000 South Africa
| | - Santosh Chokkakula
- School of Life and Health Sciences; Adikavi Nannaya University; Rajahmundry 533296 India
| | - Palakondu Lavanya
- Department of Chemistry; Annamacharya Institute of Technology and Sciences J.N.T. University; Tirupati 517 502 Andhra Pradesh India
| | - Moganavelli Singh
- Discipline of Biochemistry, School of Life Sciences; University of KwaZulu-Natal; Westville Campus, Chiltern Hills Durban 4000 South Africa
| | - Sreekanth B. Jonnalagadda
- School of Chemistry and Physics; University of KwaZulu-Natal; Westville Campus, Chilten Hills, Private Bag 54001 Durban 4000 South Africa
| |
Collapse
|
20
|
Banu AN, Balasubramanian C. Extracellular synthesis of silver nanoparticles using Bacillus megaterium against malarial and dengue vector (Diptera: Culicidae). Parasitol Res 2015; 114:4069-79. [DOI: 10.1007/s00436-015-4635-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 07/16/2015] [Indexed: 11/29/2022]
|
21
|
Bilal H, Hassan SA, Khan IA. Isolation and efficacy of entomopathogenic fungus (Metarhizium anisopliae) for the control of Aedes albopictus Skuse larvae: suspected dengue vector in Pakistan. Asian Pac J Trop Biomed 2015; 2:298-300. [PMID: 23569917 DOI: 10.1016/s2221-1691(12)60026-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 11/08/2011] [Accepted: 12/02/2011] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE To isolate the entomopathogenic fungus Metarhizium anisopliae (M. anisopliae) in the local environment, and evaluate its efficacy against the suspected dengue vector Aedes albopictus in Pakistan. METHODS According to the standard procedure, M. anisopliae was isolated from the dead mosquitoes which were collected from the field or dead after the collection. Bioassay was performed to determine its efficacy. RESULTS The results indicated that M. anisopliae had larvicidal effect with LC50 value 1.09×10(5) and LC90 value 1.90×10(13) while it took 45.41 h to kill 50% of tested population. CONCLUSIONS Taking long time to kill 50% population when compare with the synthetic insecticides, is the only drawback for the use of entomopathogenic fungus but these bio-pesticides are safe for the use.
Collapse
Affiliation(s)
- Hazrat Bilal
- Medical Entomology and Disease Vector Control, Health Services Academy, Islamabad-Pakistan
| | | | | |
Collapse
|
22
|
Abstract
Dengue is a vector-borne disease that causes a substantial public health burden within its expanding range. Several modelling studies have attempted to predict the future global distribution of dengue. However, the resulting projections are difficult to compare and are sometimes contradictory because the models differ in their approach, in the quality of the disease data that they use and in the choice of variables that drive disease distribution. In this Review, we compare the main approaches that have been used to model the future global distribution of dengue and propose a set of minimum criteria for future projections that, by analogy, are applicable to other vector-borne diseases.
Collapse
|
23
|
Larvicidal activity of titanium dioxide nanoparticles synthesized using Morinda citrifolia root extract against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus and its other effect on non-target fish. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2015. [DOI: 10.1016/s2222-1808(14)60658-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
24
|
A systematic review and meta-analysis of dengue risk with temperature change. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2014; 12:1-15. [PMID: 25546270 PMCID: PMC4306847 DOI: 10.3390/ijerph120100001] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 12/08/2014] [Indexed: 01/12/2023]
Abstract
Dengue fever (DF) is the most serious mosquito-borne viral disease in the world and is significantly affected by temperature. Although associations between DF and temperatures have been reported repeatedly, conclusions have been inconsistent. Six databases were searched up to 23 March 2014, without language and geographical restrictions. The articles that studied the correlations between temperatures and dengue were selected, and a random-effects model was used to calculate the pooled odds ratio and 95% confidence intervals. Of 1589 identified articles, 137 were reviewed further, with 33 satisfying inclusion criteria. The closest associations were observed between mean temperature from the included studies (23.2–27.7 °C) and DF (OR 35.0% per 1 °C; 95% CI 18.3%–51.6%) positively. Additionally, minimum (18.1–24.2 °C) (29.5% per 1 °C; 20.9%–38.1%) and maximum temperature (28.0–34.5 °C) (28.9%; 10.3%–47.5%) were also associated with increased dengue transmission. The OR of DF incidence increased steeply from 22 °C to 29 °C, suggesting an inflexion of DF risk between these lower and upper limits of DF risk. This discovery is helpful for government decision-makers focused on preventing and controlling dengue in areas with temperatures within this range.
Collapse
|
25
|
Phukerd U, Soonwera M. Repellency of essential oils extracted from Thai native plants against Aedes aegypti (Linn.) and Culex quinquefasciatus (Say). Parasitol Res 2014; 113:3333-40. [PMID: 25088471 DOI: 10.1007/s00436-014-3996-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 06/16/2014] [Indexed: 11/29/2022]
Abstract
Repellent activity of essential oils derived from 10 Thai native plants, belonging to three families were evaluated against female Aedes aegypti and Culex quinquefasciatus and to compare them with a commercial chemical repellents (DEET; N,N-diethyl-3-methylbenzamide 20% w/w; Sketolene Shield). Each test repellent was applied at 1, 5, and 10% concentrations for testing by arm in cage method. The results showed significant differences in repellency among the repellents by mosquito species. The protection time of the essential oils against Ae. aegypti ranged from 3 to 30 min. According to the Culex mosquito, it showed the protection time ranged from 3 to 260 min. 10 % Boesenbergia rotunda essential oil provided the best efficiency, in which protection time was 4.3 h as equal as DEET. The essential oils which exhibited protection time more than 2 h were those of 10% Zingiber zerumbet, Litsea petiolata, Curcuma zedoaria, and Zingiber cassumunar essential oils (3.1, 2.8, 2.6, and 2.3 h, respectively). The biting percentage ranged from 0.9 to 18.0% and 0.8 to 3.6% against Ae. aegypti and Cx. quinquefasciatus, respectively. The results revealed that the potential of essential oil extracted from B. rotunda, Z. zerumbet, L. petiolata, C. zedoaria, and Z. cassumunar had attributes of good repellent and deterred biting. We recommend the five essential oils for further study to develop as commercial repellents.
Collapse
Affiliation(s)
- Ubol Phukerd
- Plant Production Technology Section, Faculty of Agricultural Technology, King Mongkut's Institute of Technology Ladkrabang, Ladkrabang, Bangkok, 10520, Thailand,
| | | |
Collapse
|
26
|
Banu AN, Balasubramanian C. Optimization and synthesis of silver nanoparticles using Isaria fumosorosea against human vector mosquitoes. Parasitol Res 2014; 113:3843-51. [PMID: 25085201 DOI: 10.1007/s00436-014-4052-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Accepted: 07/23/2014] [Indexed: 11/26/2022]
Abstract
The efficacy of silver generated larvicide with the help of entomopathogenic fungi, Isaria fumosorosea (Ifr) against major vector mosquitoes Culex quinquefasciatus and Aedes aegypti. The Ifr-silver nanoparticles (AgNPs) were characterized structurally and functionally using UV-visible spectrophotometer followed by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy and Fourier transform infrared (FTIR) spectra. The optimum pH (alkaline), temperature (30 °C) and agitation (150 rpm) for AgNP synthesis and its stability were confirmed through colour change. Ae. aegypti larvae (I-IV instars) were found highly susceptible to synthesized AgNPs than the larvae of Cx. quinquefasciatus. However, the mortality rate was indirectly proportional to the larval instar and the concentration. The lethal concentration that kills 50% of the exposed larvae (LC50) and lethal concentration that kills 90% of the exposed larvae (LC90) values of the tested concentration are 0.240, 0 0.075.337, 0.430, 0.652 and 1.219, 2.210, 2.453, 2.916; 0.065, 0.075, 0.098, 0.137 and 0.558, 0.709, 0.949, 1.278 ppm with respect to 0.03 to 1.00 ppm of Ifr-AgNPs against first, second, third and fourth instars of Cx. quinquefasciatus and Ae. aegypti, respectively. This is the first report for synthesis of AgNPs using Ifr against human vector mosquitoes. Hence, Ifr-AgNPs would be significantly used as a potent mosquito larvicide.
Collapse
Affiliation(s)
- A Najitha Banu
- Department of Zoology and Microbiology, Thiagarajar College (Autonomous), Madurai, Tamil Nadu, 625009, India,
| | | |
Collapse
|
27
|
Myco-synthesis of silver nanoparticles using Beauveria bassiana against dengue vector, Aedes aegypti (Diptera: Culicidae). Parasitol Res 2014; 113:2869-77. [DOI: 10.1007/s00436-014-3948-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 05/05/2014] [Indexed: 10/25/2022]
|
28
|
Nouvellet P, Dumonteil E, Gourbière S. The improbable transmission of Trypanosoma cruzi to human: the missing link in the dynamics and control of Chagas disease. PLoS Negl Trop Dis 2013; 7:e2505. [PMID: 24244766 PMCID: PMC3820721 DOI: 10.1371/journal.pntd.0002505] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 09/16/2013] [Indexed: 01/13/2023] Open
Abstract
Chagas disease has a major impact on human health in Latin America and is becoming of global concern due to international migrations. Trypanosoma cruzi, the etiological agent of the disease, is one of the rare human parasites transmitted by the feces of its vector, as it is unable to reach the salivary gland of the insect. This stercorarian transmission is notoriously poorly understood, despite its crucial role in the ecology and evolution of the pathogen and the disease. The objective of this study was to quantify the probability of T. cruzi vectorial transmission to humans, and to use such an estimate to predict human prevalence from entomological data. We developed several models of T. cruzi transmission to estimate the probability of transmission from vector to host. Using datasets from the literature, we estimated the probability of transmission per contact with an infected triatomine to be 5.8 × 10(-4) (95%CI: [2.6 ; 11.0] × 10(-4)). This estimate was consistent across triatomine species, robust to variations in other parameters, and corresponded to 900-4,000 contacts per case. Our models subsequently allowed predicting human prevalence from vector abundance and infection rate in 7/10 independent datasets covering various triatomine species and epidemiological situations. This low probability of T. cruzi transmission reflected well the complex and unlikely mechanism of transmission via insect feces, and allowed predicting human prevalence from basic entomological data. Although a proof of principle study would now be valuable to validate our models' predictive ability in an even broader range of entomological and ecological settings, our quantitative estimate could allow switching the evaluation of disease risk and vector control program from purely entomological indexes to parasitological measures, as commonly done for other major vector borne diseases. This might lead to different quantitative perspectives as these indexes are well known not to be proportional one to another.
Collapse
Affiliation(s)
- Pierre Nouvellet
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico ; EA 4218 UPVD 'Institut de Modélisation et d'Analyses en Géo-Environnement et Santé', Université de Perpignan Via Domitia, Perpignan, France ; Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | | | | |
Collapse
|
29
|
Bai L, Morton LC, Liu Q. Climate change and mosquito-borne diseases in China: a review. Global Health 2013; 9:10. [PMID: 23497420 PMCID: PMC3605364 DOI: 10.1186/1744-8603-9-10] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 03/01/2013] [Indexed: 01/23/2023] Open
Abstract
China has experienced noticeable changes in climate over the past 100 years and the potential impact climate change has on transmission of mosquito-borne infectious diseases poses a risk to Chinese populations. The aims of this paper are to summarize what is known about the impact of climate change on the incidence and prevalence of malaria, dengue fever and Japanese encephalitis in China and to provide important information and direction for adaptation policy making. Fifty-five papers met the inclusion criteria for this study. Examination of these studies indicates that variability in temperature, precipitation, wind, and extreme weather events is linked to transmission of mosquito-borne diseases in some regions of China. However, study findings are inconsistent across geographical locations and this requires strengthening current evidence for timely development of adaptive options. After synthesis of available information we make several key adaptation recommendations including: improving current surveillance and monitoring systems; concentrating adaptation strategies and policies on vulnerable communities; strengthening adaptive capacity of public health systems; developing multidisciplinary approaches sustained by an new mechanism of inter-sectional coordination; and increasing awareness and mobilization of the general public.
Collapse
Affiliation(s)
- Li Bai
- State Key Laboratory for Infectious Diseases Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, People’s Republic of China
| | - Lindsay Carol Morton
- University of South Florida College of Public Health, 4202 E. Fowler Avenue, Tampa, FL, 33620, USA
| | - Qiyong Liu
- State Key Laboratory for Infectious Diseases Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, People’s Republic of China
- Shandong University Climate Change and Health Center, Jinan, Shandong 250012, People’s Republic China
| |
Collapse
|
30
|
Liu C, Liu Q, Lin H, Xin B, Nie J. Spatial analysis of dengue fever in Guangdong Province, China, 2001-2006. Asia Pac J Public Health 2013; 26:58-66. [PMID: 23343642 DOI: 10.1177/1010539512472356] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Guangdong Province is the area most seriously affected by dengue fever in China. In this study, we describe the spatial distribution of dengue fever in Guangdong Province from 2001 to 2006 with the objective of informing priority areas for public health planning and resource allocation. Annualized incidence at a county level was calculated and mapped to show crude incidence, excess hazard, and spatial smoothed incidence. Geographic information system-based spatial scan statistics was conducted to detect the spatial distribution pattern of dengue fever incidence at the county level. Spatial scan cluster analyses suggested that counties around Guangzhou City and Chaoshan Region were at increased risk for dengue fever (P < .01). Some spatial clusters of dengue fever were found in Guangdong Province, which allowed intervention measures to be targeted for maximum effect.
Collapse
|
31
|
Kovendan K, Murugan K, Mahesh Kumar P, Thiyagarajan P, John William S. Ovicidal, repellent, adulticidal and field evaluations of plant extract against dengue, malaria and filarial vectors. Parasitol Res 2012; 112:1205-19. [PMID: 23271569 DOI: 10.1007/s00436-012-3252-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 12/11/2012] [Indexed: 12/21/2022]
Abstract
Mosquitoes are insect vectors responsible for the transmission of parasitic and viral infections to millions of people worldwide, with substantial morbidity and mortality. Infections transmitted by mosquitoes include malaria, yellow fever, chikungunya, filariasis and other arboviruses. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The adulticidal activities of crude hexane, benzene, ethyl acetate, acetone and methanol leaf extracts of Acalypha alnifolia were assayed for their toxicity against three important vector mosquitoes, viz., Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. The adult mortality was observed after 24 h of exposure. All extracts showed moderate adulticide effects; however, the highest adult mortality was found in methanol extract were observed. The LC(50) values of A. alnifolia leaf extracts against adulticidal activity of (hexane, benzene, ethyl acetate, acetone and methanol) A. aegypti, A. stephensi and C. quinquefasciatus were the following: A. aegypti values were 371.87, 342.97, 320.17, 300.86 and 279.75 ppm; A. stephensi values were 358.35, 336.64, 306.10, 293.01 and 274.76 ppm; C. quinquefasciatus values were 383.59, 354.13, 327.74, 314.33 and 291.71 ppm. The results of the repellent activity of hexane, benzene, ethyl acetate, acetone and methanol extract of A. alnifolia plant at three different concentrations of 1.0, 3.0, and 5.0 mg/cm(2) were applied on skin of forearm in man and exposed against adult female mosquitoes. In this observation, this plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity is dependent on the strength of the plant extracts. Mean percent hatchability of the ovicidal activity was observed 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Mortality of 100 % with methanol extract of A. alnifolia was exerted at 125 and 300 ppm. The larval density was decreased after the treatment of plant extracts at the breeding sites (water bodies system) of vector mosquitoes, and hence, these plant extracts are suitable alternatives of synthetic insecticides for mosquito vector management.These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes. This study provides first report on the mosquito ovicidal, repellent and adulticidal activities of these plant extracts against mosquito vector species from India.
Collapse
Affiliation(s)
- Kalimuthu Kovendan
- Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641 046, Tamil Nadu, India.
| | | | | | | | | |
Collapse
|
32
|
Evaluation of the larvicidal efficiency of stem, roots and leaves of the weed, Parthenium hysterophorus (Family: Asteraceae) against Aedes aegypti L. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2012. [DOI: 10.1016/s2222-1808(12)60086-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
33
|
Amerasan D, Murugan K, Kovendan K, Mahesh Kumar P, Panneerselvam C, Subramaniam J, John William S, Hwang JS. Adulticidal and repellent properties of Cassia tora Linn. (Family: Caesalpinaceae) against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. Parasitol Res 2012; 111:1953-64. [PMID: 22821231 DOI: 10.1007/s00436-012-3042-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 07/05/2012] [Indexed: 12/21/2022]
Abstract
Mosquitoes have developed resistance to various synthetic insecticides, making its control increasingly difficult. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The adulticidal and repellent activities of crude hexane, chloroform, benzene, acetone, and methanol extracts of the leaf of Cassia tora were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The adult mortality was observed after 24 h of exposure. All extracts showed moderate adulticidal effects; however, the highest adult mortality observed was found in methanol extract. The LC(50) and LC(90) values of C. tora leaf extracts against adulticidal activity of (hexane, chloroform benzene, acetone, and methanol) C. quinquefasciatus, A. aegypti, and A. stephensi were the following: C. quinquefasciatus LC(50) values were 338.81, 315.73, 296.13, 279.23, and 261.03 ppm and LC(90) values were 575.77, 539.31, 513.99, 497.06, and 476.03 ppm; A. aegypti LC(50) values were 329.82, 307.31, 287.15, 269.57, and 252.03 ppm and LC(90) values were 563.24, 528.33, 496.92, 477.61, and 448.05 ppm; and A. stephensi LC(50) values were 317.28, 300.30, 277.51, 263.35, and 251.43 ppm and LC(90) values were 538.22, 512.90, 483.78, 461.08, and 430.70 ppm, respectively. The results of the repellent activity of hexane, chloroform, benzene, acetone, and methanol extracts of C. tora plant at three different concentrations of 1.0, 2.5, and 5.0 mg/cm(2) were applied on skin of forearm in man and exposed against adult female mosquitoes. In this observation, this plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity is dependent on the strength of the plant extracts. These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes. This is the first report on mosquito adulticidal and repellent activities of the reported C. tora against mosquito vectors from Southern India.
Collapse
Affiliation(s)
- Duraisamy Amerasan
- Division of Entomology, Department of Zoology, School of Life Sciences, Bharathiar University, Coimbatore, 641 046 Tamil Nadu, India
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Luo L, Liang HY, Hu YS, Liu WJ, Wang YL, Jing QL, Zheng XL, Yang ZC. Epidemiological, virological, and entomological characteristics of dengue from 1978 to 2009 in Guangzhou, China. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2012; 37:230-240. [PMID: 22548558 DOI: 10.1111/j.1948-7134.2012.00221.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
To understand its unprecedented resurgence, we examined the epidemiological, virological, and entomological features of dengue in Guangzhou during 1978-2009. Cases reported to the Guangzhou Centre for Disease Control and Prevention and data from virological and entomological surveillance were analyzed from three periods: 1978-1988, 1989-1999, and 2000-2009. Although cases decreased over time: 6,649 (1978-1988) to 6,479 (1989-1999) to 2,526 (2000-2009), geographical expansion resulted in districts with an average incidence >2.5/100,000, increasing from five (1978-1988, 1989-1999) to seven (2000-2009). Age distribution (mean age: 34.9 years) provided a trend of increasing dengue incidence among adults, and there was a significantly higher incidence among men with a sex ratio of 1.15:1 (P<0.001). Cases occurred from May through November with a peak between August and October, and a long-term trend was characterized by a three to five-year cyclical pattern. The most frequently isolated serotypes were DENV-2 (1978-1988) and DENV-1 (1989-1999 and 2000-2009). Seasonal fluctuations in immature densities of Aedes albopictus (sole transmission vector in Guangzhou) were consistent with the dengue seasonality. After a 30-year apparent absence, DENV-3 had reemerged in 2009. The current epidemiological situation is highly conducive to periodic dengue resurgences. Thus, a high degree of surveillance and strict control measures in source reduction should be maintained.
Collapse
Affiliation(s)
- Lei Luo
- School of Public Health and Tropical Medicine of South Medical University, No.1838, North Road Avenue, Guangzhou, Guangdong Province 510515, PR China
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Kumar S, Wahab N, Mishra M, Warikoo R. Evaluation of 15 Local Plant Species as Larvicidal Agents Against an Indian Strain of Dengue Fever Mosquito, Aedes aegypti L. (Diptera: Culicidae). Front Physiol 2012; 3:104. [PMID: 22536188 PMCID: PMC3332923 DOI: 10.3389/fphys.2012.00104] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 04/02/2012] [Indexed: 11/25/2022] Open
Abstract
The adverse effects of chemical insecticides-based intervention measures for the control of mosquito vectors have received wide public apprehension because of several problems like insecticide resistance, resurgence of pest species, environmental pollution, toxic hazards to humans, and non-target organisms. These problems have necessitated the need to explore and develop alternative strategies using eco-friendly, environmentally safe, bio-degradable plant products which are non-toxic to non-target organisms too. In view of this, 15 plant species were collected from local areas in New Delhi, India. Different parts of these plants were separated, dried, mechanically grinded, and sieved to get fine powder. The 200 g of each part was soaked in 1000 mL of different solvents separately and the crude extracts, thus formed, were concentrated using a vacuum evaporator at 45°C under low pressure. Each extract was screened to explore its potential as a mosquito larvicidal agent against early fourth instars of dengue vector, Aedes aegypti using WHO protocol. The preliminary screening showed that only 10 plants possessed larvicidal potential as they could result in 100% mortality at 1000 ppm. Further evaluation of the potential larvicidal extracts established the hexane leaf extract of Lantana camara to be most effective extract exhibiting a significant LC50 value of 30.71 ppm while the Phyllanthus emblica fruit extract was found to be least effective with an LC50 value of 298.93 ppm. The extracts made from different parts of other five plants; Achyranthes aspera, Zingiber officinalis, Ricinus communis, Trachyspermum ammi, and Cassia occidentalis also possessed significant larvicidal potential with LC50 values ranging from 55.0 to 74.67 ppm. Other three extracts showed moderate toxicity against A. aegypti larvae. Further investigations would be needed to isolate and identify the primary component responsible for the larvicidal efficiency of the effective plants.
Collapse
Affiliation(s)
- Sarita Kumar
- Mosquito Control Laboratory, Acharya Narendra Dev College, University of Delhi New Delhi, India
| | | | | | | |
Collapse
|
36
|
Kumar S, Warikoo R, Mishra M, Seth A, Wahab N. Larvicidal efficacy of the Citrus limetta peel extracts against Indian strains of Anopheles stephensi Liston and Aedes aegypti L. Parasitol Res 2012; 111:173-8. [PMID: 22231268 DOI: 10.1007/s00436-011-2814-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2011] [Accepted: 12/23/2011] [Indexed: 10/14/2022]
Abstract
The extracts from the peels of Citrus limetta were prepared using hexane and petroleum ether as the solvents. The larvicidal potential of each extract was assessed against dengue fever vector, Aedes aegypti, and malarial vector, Anopheles stephensi, by evaluating the toxicity effects on early fourth instars. Both the extracts were found effective against both the species. The bioassay with hexane extracts resulted in LC(50) values of 132.45 and 96.15 ppm against A. stephensi and A. aegypti, respectively; while the petroleum ether extracts from the C. limetta peels showed LC(50) values of 244.59 and 145.50 ppm, respectively. It revealed that the hexane extracts possessed 1.9-fold more larvicidal potential against A. stephensi and 1.5-fold more efficacy against A. aegypti as compared to the extracts obtained using petroleum ether as solvent. The data further revealed that the extracts were 1.4-1.7 times more effective against A. aegypti as compared to A. stephensi. The qualitative phytochemical study of the extracts showed the presence of terpenoids and flavonoids as the common phytochemical constituents in the extracts suggesting their possible role in the toxicity. Other constituents tested were not detected except alkaloids which were found to be present only in the petroleum ether extract. Further studies are needed to isolate and identify the active principles involved, their mode of action, formulated preparations for enhancing potency and stability, toxicity, and effects on non-target organisms and the environment. This could help in formulating efficient strategies for mosquito control.
Collapse
Affiliation(s)
- Sarita Kumar
- Department of Zoology, Acharya Narendra Dev College (University of Delhi), Govindpuri, New Delhi, 110019, India.
| | | | | | | | | |
Collapse
|
37
|
[Increase of entomological indices during the pre-epidemic period of dengue in Ben Tre, South Vietnam]. ACTA ACUST UNITED AC 2011; 104:313-20. [PMID: 21643648 DOI: 10.1007/s13149-011-0154-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 03/31/2011] [Indexed: 10/18/2022]
Abstract
Dengue has emerged in Vietnam 50 years ago and since has become endemo-epidemic throughout the whole country. Each year, major epidemics of dengue fever (DF) and dengue hemorrhagic fever (DHF) hit South Vietnam during the rainy season, causing significant morbidity and mortality, especially among young children. The only preventive measure is vector control, but it is often implemented too late or indiscriminately. The aim of this study was to investigate, in the pre-epidemic stage, the existence of significant changes in vector indices, which will predict DF/DHF outbreaks. We conducted a descriptive transversal study, repeated once a month for four months (March to June) in the village of Locthuan (province Ben Tre) in the Mekong's delta. Adult mosquitoes were caught in 30 houses, and larvae were collected in water holding containers of 50 houses. The houses were randomly selected. Vector densities were calculated according to the indices recommended by WHO. Virological analysis was carried out on lots of female Aedes and larvae in order to determine viral infection rates. Catches of adult mosquitoes collected 496 specimens including 329 Aedes, 139 Culex and 28 Anopheles. Aedes aegypti was present in 63% of visited homes that is an average density of 1.8 mosquitoes per house. The increase in imaginal indices during the 4 months was not significant. The survey of breeding sites of Ae. aegypti identified 1292 water containers in which 71,569 larval specimens were collected. The values of house index, container index [CI] and Breteau index [BI] increased each month, the latter from 166 to 442. This increase was significant for CI and BI. Breeding sites were mostly intra-home, mainly consisting of large and small ceramic jars. Larval density of Ae. aegypti in the containers also increased significantly over the 4 months. It was correlated with the lack of cover and predators such as Mesocyclops spp., Micronecta spp. and larvivorous fishes. Cultivation of 15 pools of 10 adult females and 29 pools of larvae (ie 1088 specimens) of Ae. aegypti failed to isolate dengue virus. The high Stegomyia indices measured in this South Vietnamese village and their increase before the rainy season reflect a situation at high risk of epidemics but cannot predict the occurrence of an outbreak in the absence of virus isolation from mosquitoes. They justify conducting an integrated vector control throughout the year.
Collapse
|
38
|
Banu S, Hu W, Hurst C, Tong S. Dengue transmission in the Asia-Pacific region: impact of climate change and socio-environmental factors. Trop Med Int Health 2011; 16:598-607. [PMID: 21320241 DOI: 10.1111/j.1365-3156.2011.02734.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To review the scientific evidence about the impact of climate change and socio-environmental factors on dengue transmission, particularly in the Asia-Pacific region. METHODS Search of the published literature on PubMed, ISI web of Knowledge and Google Scholar. Articles were included if an association between climate or socio-environmental factors and dengue transmission was assessed in any country of the Asia-Pacific region. RESULTS Twenty-two studies met the inclusion criteria. The weight of the evidence indicates that global climate change is likely to affect the seasonal and geographical distribution of dengue fever (DF) in the Asia-Pacific region. However, empirical evidence linking DF to climate change is inconsistent across geographical locations and absent in some countries where dengue is endemic. CONCLUSION Even though climate change may play an increasing role in the transmission of DF, no clear evidence shows that such impact has already occurred. More research is needed across countries to better understand the relationship between climate change and dengue transmission. Future research should also consider and adjust for the influence of important socio-environmental factors in the assessment of the climate change-related effects on dengue transmission.
Collapse
Affiliation(s)
- Shahera Banu
- School of Public Health, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Qld, Australia
| | | | | | | |
Collapse
|
39
|
Lin H, Yang L, Liu Q, Wang T, Hossain SR, Ho SC, Tian L. Time series analysis of Japanese encephalitis and weather in Linyi City, China. Int J Public Health 2011; 57:289-96. [PMID: 21308477 DOI: 10.1007/s00038-011-0236-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 09/18/2010] [Accepted: 12/02/2010] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVES To examine the relationship between meteorological factors and epidemiological pattern of Japanese encephalitis in Linyi City during 1956-2004. METHODS Autoregressive integrated moving average (ARIMA) models were used to evaluate the relationship between monthly JE incidence and weather factors. Logarithmic transformation was applied to the JE incidence series to assure the normality and homogeneity of variance of the residuals. The effect of mass vaccination on JE incidence was also evaluated using a transfer function in the time series analysis. RESULTS The analysis suggested that monthly average temperature [β = 0.0574, 95% confidence interval (CI) = (0.0172, 0.0976)] and relative humidity [β = 0.0082, 95% CI = (0.0004, 0.0158)] were positively associated with the logarithmic incidence of Japanese encephalitis after adjusting for mass vaccination in this area. CONCLUSIONS Weather variables might be treated as possible predictors of Japanese encephalitis incidence for regions with similar geographic, weather, and socio-economic conditions to Linyi, China.
Collapse
Affiliation(s)
- Hualiang Lin
- School of Public Health and Primary Care, Chinese University of Hong Kong, Hong Kong SAR, China
| | | | | | | | | | | | | |
Collapse
|