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Deb R, Singh RP, Mishra PK, Hitchins L, Reid E, Barwa AM, Patra D, Das C, Sukla I, Srivastava AK, Raj S, Mishra S, Swain M, Mondal S, Mandal U, Foster GM, Trett A, Garrod G, McKenzie L, Ali A, Morchan K, Chaudhuri I, Roy N, Gill NK, Singh C, Agarwal N, Sharma S, Stanton MC, Hemingway J, Srikantiah S, Coleman M. Impact of IRS: Four-years of entomological surveillance of the Indian Visceral Leishmaniases elimination programme. PLoS Negl Trop Dis 2021; 15:e0009101. [PMID: 34370731 PMCID: PMC8376195 DOI: 10.1371/journal.pntd.0009101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 08/19/2021] [Accepted: 07/01/2021] [Indexed: 11/18/2022] Open
Abstract
Background In 2005, Bangladesh, India and Nepal agreed to eliminate visceral leishmaniasis (VL) as a public health problem. The approach to this was through improved case detection and treatment, and controlling transmission by the sand fly vector Phlebotomus argentipes, with indoor residual spraying (IRS) of insecticide. Initially, India applied DDT with stirrup pumps for IRS, however, this did not reduce transmission. After 2015 onwards, the pyrethroid alpha-cypermethrin was applied with compression pumps, and entomological surveillance was initiated in 2016. Methods Eight sentinel sites were established in the Indian states of Bihar, Jharkhand and West Bengal. IRS coverage was monitored by household survey, quality of insecticide application was measured by HPLC, presence and abundance of the VL vector was monitored by CDC light traps, insecticide resistance was measured with WHO diagnostic assays and case incidence was determined from the VL case register KAMIS. Results Complete treatment of houses with IRS increased across all sites from 57% in 2016 to 70% of houses in 2019, rising to >80% if partial house IRS coverage is included (except West Bengal). The quality of insecticide application has improved compared to previous studies, average doses of insecticide on filters papers ranged from 1.52 times the target dose of 25mg/m2 alpha-cypermethrin in 2019 to 1.67 times in 2018. Resistance to DDT has continued to increase, but the vector was not resistant to carbamates, organophosphates or pyrethroids. The annual and seasonal abundance of P. argentipes declined between 2016 to 2019 with an overall infection rate of 0.03%. This was associated with a decline in VL incidence for the blocks represented by the sentinel sites from 1.16 per 10,000 population in 2016 to 0.51 per 10,000 in 2019. Conclusion Through effective case detection and management reducing the infection reservoirs for P. argentipes in the human population combined with IRS keeping P. argentipes abundance and infectivity low has reduced VL transmission. This combination of effective case management and vector control has now brought India within reach of the VL elimination targets. Visceral Leishmaniasis (VL), also known as kala-azar, is a major parasitic disease in South Asia (Indian subcontinent), with 85% of the disease incidence in India. Historically VL had been controlled and almost eliminated with Indoor Residual Spraying (IRS) using dichlorodiphenyltrichloroethane (DDT). However, reinitiating this approach in 2015 failed due to high insecticide resistance in the sand fly vector and poor IRS quality, meaning that VL elimination targets were not met. To improve this the National Vector Borne Disease Control Programme changed to an effective insecticide, alpha-cypermethrin and altered the mode of application to compression pumps. Sentinel sites were established to monitor the entomological indicators, these showed the positive impact of these changes from 2016 to 2019. During this period the overall incidence of disease has decreased, and India is now on track to reach it’s target incidence for VL of less than 1/1000 people at the sub-district (block) level.
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Affiliation(s)
- Rinki Deb
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | | | - Lisa Hitchins
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Emma Reid
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | - Anna Trett
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Gala Garrod
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | - Laura McKenzie
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | | | | | - Nupur Roy
- National Vector Borne Disease Control Programme, Directorate General of Health Services, Ministry of Health and Family Welfare, Delhi, India
| | - Naresh K. Gill
- National Vector Borne Disease Control Programme, Directorate General of Health Services, Ministry of Health and Family Welfare, Delhi, India
| | | | | | | | | | - Janet Hemingway
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
| | | | - Michael Coleman
- Liverpool School of Tropical Medicine, Liverpool, United Kingdom
- * E-mail:
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Tang JY, Kosgei J, Ochomo E, Ndenga BA, Ghiaseddin R, Lobo NF, Hawkes FM, O'Tousa JE. Impact of visual features on capture of Aedes aegypti with host decoy traps (HDT). MEDICAL AND VETERINARY ENTOMOLOGY 2021; 35:169-176. [PMID: 32986313 DOI: 10.1111/mve.12482] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/26/2020] [Accepted: 09/02/2020] [Indexed: 06/11/2023]
Abstract
The host decoy trap (HDT) is a surveillance trap that presents a combination of heat, visual and odour stimuli to attract bloodmeal-seeking mosquitoes. Here we employed a semi-field study to demonstrate the role of the visual attributes present on the HDT on the effectiveness of Aedes aegypti capture. Our results show that the HDT is an effective means of capturing Ae. aegypti mosquitoes in semi-field conditions, with a per trial capture rate of up to 69% across four visually distinct HDTs. The solid black coloured HDT captured more mosquitoes than HDTs with black-white stripes, black-white checkerboard patches or solid white colour by a factor of 1.9, 1.7 and 1.5, respectively. In all cases, mosquito capture was not evenly distributed on the HDT surface, with captures on the HDT's outer downwind half, away from the odour delivery, exceeding captures on the inner upwind half. We conclude that the solid black surface of the original HDT design is more effective than the other surfaces (white or black/white patterns) for the capture of Ae. aegypti. Our results demonstrate that mosquito attraction to the thermal and odorant cues of the HDT is modulated by visual information.
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Affiliation(s)
- J Y Tang
- Eck Institute for Global Health and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, U.S.A
| | - J Kosgei
- Kenya Medical Research Institute Centre for Global Health Research, Kisumu, Kenya
| | - E Ochomo
- Kenya Medical Research Institute Centre for Global Health Research, Kisumu, Kenya
| | - B A Ndenga
- Kenya Medical Research Institute Centre for Global Health Research, Kisumu, Kenya
| | - R Ghiaseddin
- Department of Applied and Computational Mathematics and Statistics, University of Notre Dame, Notre Dame, Indiana, U.S.A
| | - N F Lobo
- Eck Institute for Global Health and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, U.S.A
| | - F M Hawkes
- Natural Resources Institute, University of Greenwich at Medway, Chatham Maritime, Kent, U.K
| | - J E O'Tousa
- Eck Institute for Global Health and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, U.S.A
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Ledda C, Loreto C, Zammit C, Marconi A, Fago L, Matera S, Costanzo V, Sanzà GF, Palmucci S, Ferrante M, Costa C, Fenga C, Biondi A, Pomara C, Rapisarda V. Non‑infective occupational risk factors for hepatocellular carcinoma: A review (Review). Mol Med Rep 2017; 15:511-533. [PMID: 28000892 PMCID: PMC5364850 DOI: 10.3892/mmr.2016.6046] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/01/2016] [Indexed: 02/07/2023] Open
Abstract
Liver cancer is the second leading worldwide cause of cancer‑associated mortalities. Hepatocellular carcinoma, which accounts for the majority of liver tumors, ranks fifth among types of human cancer. Well‑established risk factors for liver cancer include the hepatitis B and C viruses, aflatoxins, alcohol consumption, and oral contraceptives. Tobacco smoking, androgenic steroids, and diabetes mellitus are suspected risk factors. Current knowledge regarding non‑infective occupational risk factors for liver cancer is inconclusive. The relevance of liver disorders to occupational medicine lies in the fact that the majority of chemicals are metabolized in the liver, and toxic metabolites generated via metabolism are the predominant cause of liver damage. However, their non‑specific clinical manifestations that are similar in a number of liver diseases make diagnosis difficult. Furthermore, concomitant conditions, such as viral hepatitis and alcohol or drug abuse, may mask liver disorders that result from occupational hepatotoxic agents and block the demonstration of an occupational cause. The identification of environmental agents that result in human cancer is a long and often difficult process. The purpose of the present review is to summarize current knowledge regarding the association of non‑infective occupational risk exposure and HCC, to encourage further research and draw attention to this global occupational public health problem.
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Affiliation(s)
- Caterina Ledda
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
- Hygiene and Public Health, Department of Medical Sciences, Surgical and Advanced Technologies ‘GF Ingrassia’, University of Catania, I-95123 Catania, Italy
| | - Carla Loreto
- Human Anatomy and Histology, Department of Biomedical and Biotechnology Sciences, University of Catania, I-95123 Catania, Italy
| | - Christian Zammit
- Anatomy Department, Faculty of Medicine and Surgery, University of Malta, MSD-2080 Msida, Malta
| | - Andrea Marconi
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Lucrezia Fago
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Serena Matera
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Valentina Costanzo
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
| | - Giovanni Fuccio Sanzà
- Division of Radiology, ‘Policlinico-Vittorio Emanuele’ University Hospital, University of Catania, I-95123 Catania, Italy
| | - Stefano Palmucci
- Division of Radiology, ‘Policlinico-Vittorio Emanuele’ University Hospital, University of Catania, I-95123 Catania, Italy
| | - Margherita Ferrante
- Hygiene and Public Health, Department of Medical Sciences, Surgical and Advanced Technologies ‘GF Ingrassia’, University of Catania, I-95123 Catania, Italy
| | - Chiara Costa
- Occupational Medicine, Department of the Environment, Safety, Territory, Food and Health Sciences, University of Messina, I-98125 Messina, Italy
| | - Concettina Fenga
- Occupational Medicine, Department of the Environment, Safety, Territory, Food and Health Sciences, University of Messina, I-98125 Messina, Italy
| | - Antonio Biondi
- General Surgery, Department of General Surgery and Medical-Surgical Specialties, University of Catania, I-95123 Catania, Italy
| | - Cristoforo Pomara
- Anatomy Department, Faculty of Medicine and Surgery, University of Malta, MSD-2080 Msida, Malta
- Forensic Pathology, Department of Clinical and Experimental Medicine, University of Foggia, I-71122 Foggia, Italy
| | - Venerando Rapisarda
- Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, I-95123 Catania, Italy
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Tetreau G, Stalinski R, David JP, Després L. Monitoring resistance to Bacillus thuringiensis subsp. israelensis in the field by performing bioassays with each Cry toxin separately. Mem Inst Oswaldo Cruz 2015; 108:894-900. [PMID: 24037105 PMCID: PMC3970644 DOI: 10.1590/0074-0276130155] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 04/10/2013] [Indexed: 02/04/2023] Open
Abstract
Bacillus thuringiensis subsp. israelensis (Bti) is increasingly used worldwide for mosquito control and is the only larvicide used in the French Rhône-Alpes region since decades. The artificial selection of mosquitoes with field-persistent Bti collected in breeding sites from this region led to a moderate level of resistance to Bti, but to relatively high levels of resistance to individual Bti Cry toxins. Based on this observation, we developed a bioassay procedure using each Bti Cry toxin separately to detect cryptic Bti-resistance evolving in field mosquito populations. Although no resistance to Bti was detected in none of the three mosquito species tested (Aedes rusticus, Aedes sticticus and Aedes vexans), an increased tolerance to Cry4Aa (3.5-fold) and Cry11Aa toxins (8-fold) was found in one Ae. sticticus population compared to other populations of the same species, suggesting that resistance to Bti may be arising in this population. This study confirms previous works showing a lack of Bti resistance in field mosquito populations treated for decades with this bioinsecticide. It also provides a first panorama of their susceptibility status to individual Bti Cry toxins. In combination with bioassays with Bti, bioassays with separate Cry toxins allow a more sensitive monitoring of Bti-resistance in the field.
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Feng L, Fu C, Yuan D, Miao W. A P450 gene associated with robust resistance to DDT in ciliated protozoan, Tetrahymena thermophila by efficient degradation. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2014; 149:126-132. [PMID: 24607688 DOI: 10.1016/j.aquatox.2014.02.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 02/05/2014] [Accepted: 02/06/2014] [Indexed: 06/03/2023]
Abstract
Analysis of metabolic mechanisms of dichlorodiphenyltrichloroethane (DDT) accumulation and degradation in microorganisms, which could be used to reduce its hazard to higher organisms at the higher in the food chain, have not been investigated. Robust resistance to DDT (grows well in 256 mg/L DDT) and a surprising ability to degrade DDT (more than 70% DDT within 4h) were found in the ciliated protozoan Tetrahymena thermophila. A P450 gene (CYP5013C2) was found to respond specifically to DDT treatment. In the presence of 256 mg/L DDT, cells with overexpressing CYP5013C2 (p450-OE) grew faster and degraded DDT more efficiently than wild-type (WT) cells, while cells with CYP5013C2 partially knocked down (p450-KD) grew slower and exhibited reduced ability to degrade DDT compared to WT cells. Both dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) were detected in cells after exposure to DDT, and the concentration of DDD in the p450-OE strain gradually decreased from 0.5 to 4h. Thus, we argue that this P450 gene (CYP5013C2), by efficiently degrading DDT to DDD, is associated with robust resistance to DDT in Tetrahymena, and that a strain overexpressing this gene has the potential to serve as bioreactor that degrades environmental DDT.
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Affiliation(s)
- Lifang Feng
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China.
| | - Chengjie Fu
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Dongxia Yuan
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wei Miao
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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Tetreau G, Patil C, Chandor-Proust A, Salunke B, Patil S, Després L. Production of the bioinsecticide Bacillus thuringiensis
subsp. israelensis
with deltamethrin increases toxicity towards mosquito larvae. Lett Appl Microbiol 2013; 57:151-6. [DOI: 10.1111/lam.12089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 04/10/2013] [Accepted: 04/15/2013] [Indexed: 11/28/2022]
Affiliation(s)
- G. Tetreau
- Laboratoire d'Ecologie Alpine; LECA-UMR 5553; Université de Grenoble 1; Grenoble Cedex 09 France
| | - C.D. Patil
- School of Life Sciences; North Maharashtra University; Jalgaon Maharashtra India
| | - A. Chandor-Proust
- Laboratoire d'Ecologie Alpine; LECA-UMR 5553; Université de Grenoble 1; Grenoble Cedex 09 France
| | - B.K. Salunke
- School of Life Sciences; North Maharashtra University; Jalgaon Maharashtra India
| | - S.V. Patil
- School of Life Sciences; North Maharashtra University; Jalgaon Maharashtra India
| | - L. Després
- Laboratoire d'Ecologie Alpine; LECA-UMR 5553; Université de Grenoble 1; Grenoble Cedex 09 France
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Uccello M, Malaguarnera G, Corriere T, Biondi A, Basile F, Malaguarnera M. Risk of hepatocellular carcinoma in workers exposed to chemicals. HEPATITIS MONTHLY 2012; 12:e5943. [PMID: 23162599 PMCID: PMC3496877 DOI: 10.5812/hepatmon.5943] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 09/28/2011] [Accepted: 10/08/2011] [Indexed: 12/11/2022]
Abstract
CONTEXT Studies on experimental animals have shown liver is a common target of chemical carcinogens; this might suggest that occupational exposure to chemicals is another risk factor for HCC. However, the relationship between occupation and liver cancer has not been extensively studied, with the exception of the known association between vinyl chloride and angiosarcoma of the liver. EVIDENCE ACQUISITION A MEDLINE and conventional search of the past 50 years of the medical literature was performed to identify relevant articles on incidence and mechanisms of HCC due to occupational exposure to chemicals. Several important edited books and monographs were also identified and reviewed. RESULTS While laboratory data clearly indicate that the liver is an important target of chemical carcinogenesis, epidemiological studies provide very limited evidence on occupational risk factors for HCC. Nevertheless, we found some case reports and epidemiological data showing a moderately increased risk of HCC development in people exposed to vinyl chloride, organic solvents, pesticides, polychlorinated biphenyls, and arsenic. CONCLUSIONS Occupational exposure to chemicals may be another risk factor for HCC development, but the interpretation of currently available findings is limited by the small number of studies, questionable accuracy of the diagnosis of liver cancer, and potential confounding or modifying factors such as chronic hepatitis virus infection and alcohol consumption. Further relevant investigations are required for clarifying the actual contribution of occupational exposure to chemicals in HCC development.
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Affiliation(s)
- Mario Uccello
- Research Center “The Great Senescence”, University of Catania, Catania, Italy
| | - Giulia Malaguarnera
- Research Center “The Great Senescence”, University of Catania, Catania, Italy
| | - Thea Corriere
- Research Center “The Great Senescence”, University of Catania, Catania, Italy
| | - Antonio Biondi
- Department of General Surgery, University of Catania, Catania, Italy
| | - Francesco Basile
- Department of General Surgery, University of Catania, Catania, Italy
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Tetreau G, Bayyareddy K, Jones CM, Stalinski R, Riaz MA, Paris M, David JP, Adang MJ, Després L. Larval midgut modifications associated with Bti resistance in the yellow fever mosquito using proteomic and transcriptomic approaches. BMC Genomics 2012; 13:248. [PMID: 22703117 PMCID: PMC3460780 DOI: 10.1186/1471-2164-13-248] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 05/25/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Bacillus thuringiensis var. israelensis (Bti) is a natural larval mosquito pathogen producing pore-forming toxins targeting the midgut of Diptera larvae. It is used worldwide for mosquito control. Resistance mechanisms of an Aedes aegypti laboratory strain selected for 30 generations with field-collected leaf litter containing Bti toxins were investigated in larval midguts at two levels: 1. gene transcription using DNA microarray and RT-qPCR and 2. differential expression of brush border membrane proteins using DIGE (Differential In Gel Electrophoresis). RESULTS Several Bti Cry toxin receptors including alkaline phosphatases and N-aminopeptidases and toxin-binding V-ATPases exhibited altered expression levels in the resistant strain. The under-expression of putative Bti-receptors is consistent with Bt-resistance mechanisms previously described in Lepidoptera. Four soluble metalloproteinases were found under-transcribed together with a drastic decrease of metalloproteinases activity in the resistant strain, suggesting a role in resistance by decreasing the amount of activated Cry toxins in the larval midgut. CONCLUSIONS By combining transcriptomic and proteomic approaches, we detected expression changes at nearly each step of the ingestion-to-infection process, providing a short list of genes and proteins potentially involved in Bti-resistance whose implication needs to be validated. Collectively, these results open the way to further functional analyses to better characterize Bti-resistance mechanisms in mosquitoes.
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Affiliation(s)
- Guillaume Tetreau
- Laboratoire d'Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, BP 53, 38041 Grenoble cedex 09, France.
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Emergence and prevalence of human vector-borne diseases in sink vector populations. PLoS One 2012; 7:e36858. [PMID: 22629337 PMCID: PMC3356347 DOI: 10.1371/journal.pone.0036858] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Accepted: 04/16/2012] [Indexed: 01/04/2023] Open
Abstract
Vector-borne diseases represent a major public health concern in most tropical and subtropical areas, and an emerging threat for more developed countries. Our understanding of the ecology, evolution and control of these diseases relies predominantly on theory and data on pathogen transmission in large self-sustaining ‘source’ populations of vectors representative of highly endemic areas. However, there are numerous places where environmental conditions are less favourable to vector populations, but where immigration allows them to persist. We built an epidemiological model to investigate the dynamics of six major human vector borne-diseases in such non self-sustaining ‘sink’ vector populations. The model was parameterized through a review of the literature, and we performed extensive sensitivity analysis to look at the emergence and prevalence of the pathogen that could be encountered in these populations. Despite the low vector abundance in typical sink populations, all six human diseases were able to spread in 15–55% of cases after accidental introduction. The rate of spread was much more strongly influenced by vector longevity, immigration and feeding rates, than by transmission and virulence of the pathogen. Prevalence in humans remained lower than 5% for dengue, leishmaniasis and Japanese encephalitis, but substantially higher for diseases with longer duration of infection; malaria and the American and African trypanosomiasis. Vector-related parameters were again the key factors, although their influence was lower than on pathogen emergence. Our results emphasize the need for ecology and evolution to be thought in the context of metapopulations made of a mosaic of sink and source habitats, and to design vector control program not only targeting areas of high vector density, but working at a larger spatial scale.
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