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Almeida CE, Faucher L, Lavina M, Costa J, Harry M. Molecular Individual-Based Approach on Triatoma brasiliensis: Inferences on Triatomine Foci, Trypanosoma cruzi Natural Infection Prevalence, Parasite Diversity and Feeding Sources. PLoS Negl Trop Dis 2016; 10:e0004447. [PMID: 26891047 PMCID: PMC4758651 DOI: 10.1371/journal.pntd.0004447] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 01/20/2016] [Indexed: 11/19/2022] Open
Abstract
We used an individual-based molecular multisource approach to assess the epidemiological importance of Triatoma brasiliensis collected in distinct sites and ecotopes in Rio Grande do Norte State, Brazil. In the semi-arid zones of Brazil, this blood sucking bug is the most important vector of Trypanosoma cruzi--the parasite that causes Chagas disease. First, cytochrome b (cytb) and microsatellite markers were used for inferences on the genetic structure of five populations (108 bugs). Second, we determined the natural T. cruzi infection prevalence and parasite diversity in 126 bugs by amplifying a mini-exon gene from triatomine gut contents. Third, we identified the natural feeding sources of 60 T. brasiliensis by using the blood meal content via vertebrate cytb analysis. Demographic inferences based on cytb variation indicated expansion events in some sylvatic and domiciliary populations. Microsatellite results indicated gene flow between sylvatic and anthropic (domiciliary and peridomiciliary) populations, which threatens vector control efforts because sylvatic population are uncontrollable. A high natural T. cruzi infection prevalence (52-71%) and two parasite lineages were found for the sylvatic foci, in which 68% of bugs had fed on Kerodon rupestris (Rodentia: Caviidae), highlighting it as a potential reservoir. For peridomiciliary bugs, Galea spixii (Rodentia: Caviidae) was the main mammal feeding source, which may reinforce previous concerns about the potential of this animal to link the sylvatic and domiciliary T. cruzi cycles.
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Affiliation(s)
- Carlos Eduardo Almeida
- Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas (UNESP), Araraquara, SP, Brasil
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
- Programa de Pós-Graduação em Ecologia e Monitoramento Ambiental – PPGEMA, Universidade Federal da Paraíba, PB, Brasil
| | - Leslie Faucher
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Morgane Lavina
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Jane Costa
- Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz – Fiocruz, Rio de Janeiro, RJ, Brasil
| | - Myriam Harry
- UMR EGCE (Evolution, Genome, Comportment, Ecologie), CNRS-IRD-Univ. Paris-Sud, IDEEV, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
- Université Paris-Sud, Orsay, France
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Dias JVL, Queiroz DRM, Martins HR, Gorla DE, Pires HHR, Diotaiuti L. Spatial distribution of triatomines in domiciles of an urban area of the Brazilian Southeast Region. Mem Inst Oswaldo Cruz 2016; 111:43-50. [PMID: 26814643 PMCID: PMC4727435 DOI: 10.1590/0074-02760150352] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 12/08/2015] [Indexed: 11/25/2022] Open
Abstract
Reports of triatomine infestation in urban areas have increased. We analysed the spatial distribution of infestation by triatomines in the urban area of Diamantina, in the state of Minas Gerais, Brazil. Triatomines were obtained by community-based entomological surveillance. Spatial patterns of infestation were analysed by Ripley's K function and Kernel density estimator. Normalised difference vegetation index (NDVI) and land cover derived from satellite imagery were compared between infested and uninfested areas. A total of 140 adults of four species were captured (100 Triatoma vitticeps, 25 Panstrongylus geniculatus, 8 Panstrongylus megistus, and 7 Triatoma arthurneivai specimens). In total, 87.9% were captured within domiciles. Infection by trypanosomes was observed in 19.6% of 107 examined insects. The spatial distributions ofT. vitticeps, P. geniculatus, T. arthurneivai, and trypanosome-positive triatomines were clustered, occurring mainly in peripheral areas. NDVI values were statistically higher in areas infested by T. vitticeps and P. geniculatus. Buildings infested by these species were located closer to open fields, whereas infestations of P. megistus and T. arthurneivai were closer to bare soil. Human occupation and modification of natural areas may be involved in triatomine invasion, exposing the population to these vectors.
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Affiliation(s)
- João Victor Leite Dias
- Fundação Oswaldo Cruz, Centro de Pesquisas René Rachou, Laboratório de
Triatomíneos e Epidemiologia da Doença de Chagas, Belo Horizonte, MG, Brasil
- Universidade Federal dos Vales do Jequitinhonha e Mucuri, Departamento
de Farmácia, Laboratório de Doenças Parasitárias, Diamantina, MG, Brasil
| | - Dimas Ramon Mota Queiroz
- Universidade Federal dos Vales do Jequitinhonha e Mucuri, Departamento
de Farmácia, Laboratório de Doenças Parasitárias, Diamantina, MG, Brasil
| | - Helen Rodrigues Martins
- Universidade Federal dos Vales do Jequitinhonha e Mucuri, Departamento
de Farmácia, Laboratório de Doenças Parasitárias, Diamantina, MG, Brasil
| | - David Eladio Gorla
- Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto
Multidisciplinario de Biología Vegetal, Córdoba, Argentina
| | - Herton Helder Rocha Pires
- Universidade Federal dos Vales do Jequitinhonha e Mucuri, Departamento
de Farmácia, Laboratório de Doenças Parasitárias, Diamantina, MG, Brasil
| | - Liléia Diotaiuti
- Fundação Oswaldo Cruz, Centro de Pesquisas René Rachou, Laboratório de
Triatomíneos e Epidemiologia da Doença de Chagas, Belo Horizonte, MG, Brasil
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Liu Q, Zhou XN. Preventing the transmission of American trypanosomiasis and its spread into non-endemic countries. Infect Dis Poverty 2015; 4:60. [PMID: 26715535 PMCID: PMC4693433 DOI: 10.1186/s40249-015-0092-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 12/11/2015] [Indexed: 11/10/2022] Open
Abstract
American trypanosomiasis, commonly known as Chagas disease, is caused by the flagellate protozoan parasite Trypanosoma cruzi. An estimated eight million people infected with T. cruzi currently reside in the endemic regions of Latin America. However, as the disease has now been imported into many non-endemic countries outside of Latin America, it has become a global health issue. We reviewed the transmission patterns and current status of disease spread pertaining to American trypanosomiasis at the global level, as well as recent advances in research. Based on an analysis of the gaps in American trypanosomiasis control, we put forward future research priorities that must be implemented to stop the global spread of the disease.
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Affiliation(s)
- Qin Liu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health;, WHO Collaborating Center for Tropical Diseases, Shanghai, 200025, P. R. China
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory of Parasite and Vector Biology, Ministry of Health;, WHO Collaborating Center for Tropical Diseases, Shanghai, 200025, P. R. China.
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Medone P, Ceccarelli S, Parham PE, Figuera A, Rabinovich JE. The impact of climate change on the geographical distribution of two vectors of Chagas disease: implications for the force of infection. Philos Trans R Soc Lond B Biol Sci 2015; 370:rstb.2013.0560. [PMID: 25688019 DOI: 10.1098/rstb.2013.0560] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Chagas disease, caused by the parasite Trypanosoma cruzi, is the most important vector-borne disease in Latin America. The vectors are insects belonging to the Triatominae (Hemiptera, Reduviidae), and are widely distributed in the Americas. Here, we assess the implications of climatic projections for 2050 on the geographical footprint of two of the main Chagas disease vectors: Rhodnius prolixus (tropical species) and Triatoma infestans (temperate species). We estimated the epidemiological implications of current to future transitions in the climatic niche in terms of changes in the force of infection (FOI) on the rural population of two countries: Venezuela (tropical) and Argentina (temperate). The climatic projections for 2050 showed heterogeneous impact on the climatic niches of both vector species, with a decreasing trend of suitability of areas that are currently at high-to-moderate transmission risk. Consequently, climatic projections affected differently the FOI for Chagas disease in Venezuela and Argentina. Despite the heterogeneous results, our main conclusions point out a decreasing trend in the number of new cases of Tr. cruzi human infections per year between current and future conditions using a climatic niche approach.
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Affiliation(s)
- Paula Medone
- Centro de Estudios Parasitológicos y de Vectores (CONICET, CCT- La Plata, UNLP), Universidad Nacional de La Plata, Bulevar 120s/n e/61 y 62. La Plata, Provincia de Buenos Aires B1902CHX, Argentina
| | - Soledad Ceccarelli
- Centro de Estudios Parasitológicos y de Vectores (CONICET, CCT- La Plata, UNLP), Universidad Nacional de La Plata, Bulevar 120s/n e/61 y 62. La Plata, Provincia de Buenos Aires B1902CHX, Argentina
| | - Paul E Parham
- Department of Public Health and Policy, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 3GL, UK Grantham Institute for Climate Change, Department of Infectious Disease Epidemiology, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK
| | - Andreína Figuera
- Instituto de Investigaciones Biomédicas (BIOMED), Universidad de Carabobo, Sede Aragua, Maracay, Venezuela
| | - Jorge E Rabinovich
- Centro de Estudios Parasitológicos y de Vectores (CONICET, CCT- La Plata, UNLP), Universidad Nacional de La Plata, Bulevar 120s/n e/61 y 62. La Plata, Provincia de Buenos Aires B1902CHX, Argentina
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Abad-Franch F, Lima MM, Sarquis O, Gurgel-Gonçalves R, Sánchez-Martín M, Calzada J, Saldaña A, Monteiro FA, Palomeque FS, Santos WS, Angulo VM, Esteban L, Dias FBS, Diotaiuti L, Bar ME, Gottdenker NL. On palms, bugs, and Chagas disease in the Americas. Acta Trop 2015. [PMID: 26196330 DOI: 10.1016/j.actatropica.2015.07.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Palms are ubiquitous across Neotropical landscapes, from pristine forests or savannahs to large cities. Although palms provide useful ecosystem services, they also offer suitable habitat for triatomines and for Trypanosoma cruzi mammalian hosts. Wild triatomines often invade houses by flying from nearby palms, potentially leading to new cases of human Chagas disease. Understanding and predicting triatomine-palm associations and palm infestation probabilities is important for enhancing Chagas disease prevention in areas where palm-associated vectors transmit T. cruzi. We present a comprehensive overview of palm infestation by triatomines in the Americas, combining a thorough reanalysis of our published and unpublished records with an in-depth review of the literature. We use site-occupancy modeling (SOM) to examine infestation in 3590 palms sampled with non-destructive methods, and standard statistics to describe and compare infestation in 2940 palms sampled by felling-and-dissection. Thirty-eight palm species (18 genera) have been reported to be infested by ∼39 triatomine species (10 genera) from the USA to Argentina. Overall infestation varied from 49.1-55.3% (SOM) to 62.6-66.1% (dissection), with important heterogeneities among sub-regions and particularly among palm species. Large palms with complex crowns (e.g., Attalea butyracea, Acrocomia aculeata) and some medium-crowned palms (e.g., Copernicia, Butia) are often infested; in slender, small-crowned palms (e.g., Euterpe) triatomines associate with vertebrate nests. Palm infestation tends to be higher in rural settings, but urban palms can also be infested. Most Rhodnius species are probably true palm specialists, whereas Psammolestes, Eratyrus, Cavernicola, Panstrongylus, Triatoma, Alberprosenia, and some Bolboderini seem to use palms opportunistically. Palms provide extensive habitat for enzootic T. cruzi cycles and a critical link between wild cycles and transmission to humans. Unless effective means to reduce contact between people and palm-living triatomines are devised, palms will contribute to maintaining long-term and widespread, albeit possibly low-intensity, transmission of human Chagas disease.
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Affiliation(s)
- Fernando Abad-Franch
- Laboratório de Ecologia de Doenças Transmissíveis na Amazônia, Instituto Leônidas e Maria Deane - Fiocruz, Rua Teresina 476, Manaus 69057-070, Amazonas, Brazil; Laboratório de Triatomíneos e Epidemiologia da Doença de Chagas, Centro de Pesquisa René Rachou - Fiocruz, Av. Augusto de Lima 1715, Belo Horizonte 30190-002, Minas Gerais, Brazil.
| | - Marli M Lima
- Laboratório de Ecoepidemiologia da Doença de Chagas, Instituto Oswaldo Cruz - Fiocruz, Av. Brasil 4365, Rio de Janeiro 21045-900, Rio de Janeiro, Brazil
| | - Otília Sarquis
- Laboratório de Ecoepidemiologia da Doença de Chagas, Instituto Oswaldo Cruz - Fiocruz, Av. Brasil 4365, Rio de Janeiro 21045-900, Rio de Janeiro, Brazil
| | - Rodrigo Gurgel-Gonçalves
- Laboratório de Parasitologia Médica e Biologia de Vetores, Faculdade de Medicina, Universidade de Brasília, Asa Norte, Brasília 70904-970, Distrito Federal, Brazil
| | - María Sánchez-Martín
- Instituto de Salud Global de Barcelona - ISGlobal, c/ Rosselló 132, 5° 2ª, 08036 Barcelona, Catalunya, Spain
| | - José Calzada
- Insituto Conmemorativo Gorgas de Estudios de la Salud, Av. Justo Arosemena y Calle 32, Panamá 0816-02593, Panama
| | - Azael Saldaña
- Insituto Conmemorativo Gorgas de Estudios de la Salud, Av. Justo Arosemena y Calle 32, Panamá 0816-02593, Panama
| | - Fernando A Monteiro
- Laboratório de Epidemiologia e Sistemática Molecular, Instituto Oswaldo Cruz - Fiocruz, Av. Brasil 4365, Rio de Janeiro 21045-900, Rio de Janeiro, Brazil
| | - Francisco S Palomeque
- Centers for Disease Control and Prevention, 1600 Clifton Road, Atlanta, GA 30329-4027, USA
| | - Walter S Santos
- Laboratório de Doença de Chagas, Seção de Parasitologia, Instituto Evandro Chagas - SVS/MS, Rodovia BR 316 km 7 s/n, 67030-000 Ananindeua, Pará, Brazil
| | - Victor M Angulo
- Centro de Investigaciones en Enfermedades Tropicales - CINTROP, Universidad Industrial de Santander, Calle 9 no. 27, Piedecuesta 680002, Santander, Colombia
| | - Lyda Esteban
- Centro de Investigaciones en Enfermedades Tropicales - CINTROP, Universidad Industrial de Santander, Calle 9 no. 27, Piedecuesta 680002, Santander, Colombia
| | - Fernando B S Dias
- Laboratório de Triatomíneos e Epidemiologia da Doença de Chagas, Centro de Pesquisa René Rachou - Fiocruz, Av. Augusto de Lima 1715, Belo Horizonte 30190-002, Minas Gerais, Brazil
| | - Liléia Diotaiuti
- Laboratório de Triatomíneos e Epidemiologia da Doença de Chagas, Centro de Pesquisa René Rachou - Fiocruz, Av. Augusto de Lima 1715, Belo Horizonte 30190-002, Minas Gerais, Brazil
| | - María Esther Bar
- Laboratorio de Artrópodos, Facultad de Ciencia Exactas y Naturales, Universidad Nacional del Nordeste, Av. Libertad 5470, CP 3400 Corrientes, Argentina
| | - Nicole L Gottdenker
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
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Peterson JK, Bartsch SM, Lee BY, Dobson AP. Broad patterns in domestic vector-borne Trypanosoma cruzi transmission dynamics: synanthropic animals and vector control. Parasit Vectors 2015; 8:537. [PMID: 26489493 PMCID: PMC4618875 DOI: 10.1186/s13071-015-1146-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 10/05/2015] [Indexed: 12/22/2022] Open
Abstract
Background Chagas disease (caused by Trypanosoma cruzi) is the most important neglected tropical disease (NTD) in Latin America, infecting an estimated 5.7 million people in the 21 countries where it is endemic. It is one of the NTDs targeted for control and elimination by the 2020 London Declaration goals, with the first goal being to interrupt intra-domiciliary vector-borne T. cruzi transmission. A key question in domestic T. cruzi transmission is the role that synanthropic animals play in T. cruzi transmission to humans. Here, we ask, (1) do synanthropic animals need to be targeted in Chagas disease prevention policies?, and (2) how does the presence of animals affect the efficacy of vector control? Methods We developed a simple mathematical model to simulate domestic vector-borne T.cruzi transmission and to specifically examine the interaction between the presence of synanthropic animals and effects of vector control. We used the model to explore how the interactions between triatomine bugs, humans and animals impact the number and proportion of T. cruzi-infected bugs and humans. We then examined how T. cruzi dynamics change when control measures targeting vector abundance are introduced into the system. Results We found that the presence of synanthropic animals slows the speed of T. cruzi transmission to humans, and increases the sensitivity of T. cruzi transmission dynamics to vector control measures at comparable triatomine carrying capacities. However, T. cruzi transmission is amplified when triatomine carrying capacity increases with the abundance of syntathoropic hosts. Conclusions Our results suggest that in domestic T. cruzi transmission scenarios where no vector control measures are in place, a reduction in synanthropic animals may slow T. cruzi transmission to humans, but it would not completely eliminate transmission. To reach the 2020 goal of interrupting intra-domiciliary T. cruzi transmission, it is critical to target vector populations. Additionally, where vector control measures are in place, synanthropic animals may be beneficial.
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Affiliation(s)
- Jennifer K Peterson
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.
| | - Sarah M Bartsch
- Public Health Computational and Operations Research (PHICOR), John Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Bruce Y Lee
- Public Health Computational and Operations Research (PHICOR), John Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Andrew P Dobson
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.
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Controlled but not cured: Structural processes and explanatory models of Chagas disease in tropical Bolivia. Soc Sci Med 2015; 145:7-16. [PMID: 26432176 DOI: 10.1016/j.socscimed.2015.09.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 09/13/2015] [Accepted: 09/14/2015] [Indexed: 11/23/2022]
Abstract
Dressler (2001:456) characterizes medical anthropology as divided between two poles: the constructivist, which focuses on the "meaning and significance that events have for people," and the structuralist, which emphasizes socioeconomic processes and relationships. This study synthesizes structuralist and constructivist perspectives by investigating how structural processes impact explanatory models of Chagas disease in a highly endemic area. The research took place from March-June 2013 through the Centro Medico Humberto Parra, a non-profit clinic servicing low income populations in Palacios, Bolivia and surrounding communities. Semistructured interviews (n = 68) and consensus analysis questionnaires (n = 48) were administered to people dealing with Chagas disease. In the interview narratives, respondents link Chagas disease with experiences of marginalization and rural poverty, and describe multilayered impediments to accessing treatment. They often view the disease as incurable, but this reflects inconsistent messages from the biomedical system. The consensus analysis results show strong agreement on knowledge of the vector, ethnomedical treatment, and structural factors related to Chagas disease. In interpreting Chagas disease, respondents account for the structural factors which place them at risk and impede access to care.
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58
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The Burden of Chagas Disease: Estimates and Challenges. Glob Heart 2015; 10:139-44. [DOI: 10.1016/j.gheart.2015.06.001] [Citation(s) in RCA: 118] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 06/04/2015] [Indexed: 11/20/2022] Open
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Hashimoto K, Yoshioka K. Certifying achievement in the control of Chagas disease native vectors: what is a viable scenario? Mem Inst Oswaldo Cruz 2015; 109:834-7. [PMID: 25317713 PMCID: PMC4238779 DOI: 10.1590/0074-0276140251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 09/08/2014] [Indexed: 11/22/2022] Open
Abstract
As an evaluation scheme, we propose certifying for “control”, as alternative to
“interruption”, of Chagas disease transmission by native vectors, to project a more
achievable and measurable goal and sharing good practices through an “open online
platform” rather than “formal certification” to make the key knowledge more
accumulable and accessible.
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60
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Forlani L, Pedrini N, Girotti JR, Mijailovsky SJ, Cardozo RM, Gentile AG, Hernández-Suárez CM, Rabinovich JE, Juárez MP. Biological Control of the Chagas Disease Vector Triatoma infestans with the Entomopathogenic Fungus Beauveria bassiana Combined with an Aggregation Cue: Field, Laboratory and Mathematical Modeling Assessment. PLoS Negl Trop Dis 2015; 9:e0003778. [PMID: 25969989 PMCID: PMC4430541 DOI: 10.1371/journal.pntd.0003778] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 04/22/2015] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Current Chagas disease vector control strategies, based on chemical insecticide spraying, are growingly threatened by the emergence of pyrethroid-resistant Triatoma infestans populations in the Gran Chaco region of South America. METHODOLOGY AND FINDINGS We have already shown that the entomopathogenic fungus Beauveria bassiana has the ability to breach the insect cuticle and is effective both against pyrethroid-susceptible and pyrethroid-resistant T. infestans, in laboratory as well as field assays. It is also known that T. infestans cuticle lipids play a major role as contact aggregation pheromones. We estimated the effectiveness of pheromone-based infection boxes containing B. bassiana spores to kill indoor bugs, and its effect on the vector population dynamics. Laboratory assays were performed to estimate the effect of fungal infection on female reproductive parameters. The effect of insect exuviae as an aggregation signal in the performance of the infection boxes was estimated both in the laboratory and in the field. We developed a stage-specific matrix model of T. infestans to describe the fungal infection effects on insect population dynamics, and to analyze the performance of the biopesticide device in vector biological control. CONCLUSIONS The pheromone-containing infective box is a promising new tool against indoor populations of this Chagas disease vector, with the number of boxes per house being the main driver of the reduction of the total domestic bug population. This ecologically safe approach is the first proven alternative to chemical insecticides in the control of T. infestans. The advantageous reduction in vector population by delayed-action fungal biopesticides in a contained environment is here shown supported by mathematical modeling.
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Affiliation(s)
- Lucas Forlani
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET, CCT-La Plata, UNLP), Facultad de Ciencias Médicas, La Plata, Argentina
| | - Nicolás Pedrini
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET, CCT-La Plata, UNLP), Facultad de Ciencias Médicas, La Plata, Argentina
| | - Juan R. Girotti
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET, CCT-La Plata, UNLP), Facultad de Ciencias Médicas, La Plata, Argentina
| | - Sergio J. Mijailovsky
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET, CCT-La Plata, UNLP), Facultad de Ciencias Médicas, La Plata, Argentina
| | - Rubén M. Cardozo
- Instituto de Patología Experimental, Facultad de Ciencias de la Salud, Universidad Nacional de Salta, Salta, Argentina
- Coordinación de Gestión Epidemiológica, Ministerio de Salud Pública, Salta, Argentina
| | - Alberto G. Gentile
- Coordinación de Gestión Epidemiológica, Ministerio de Salud Pública, Salta, Argentina
| | | | - Jorge E. Rabinovich
- Centro de Estudios Parasitológicos y de Vectores (CEPAVE, CONICET, CCT-La Plata, UNLP), La Plata, Argentina
| | - M. Patricia Juárez
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP, CONICET, CCT-La Plata, UNLP), Facultad de Ciencias Médicas, La Plata, Argentina
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Gaspe MS, Provecho YM, Piccinali RV, Gürtler RE. Where do these bugs come from? Phenotypic structure of Triatoma infestans populations after control interventions in the Argentine Chaco. Mem Inst Oswaldo Cruz 2015; 110:310-8. [PMID: 25946158 PMCID: PMC4489468 DOI: 10.1590/0074-02760140376] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 03/18/2015] [Indexed: 11/22/2022] Open
Abstract
House re-invasion by native triatomines after insecticide-based control campaigns
represents a major threat for Chagas disease vector control. We conducted a
longitudinal intervention study in a rural section (Area III, 407 houses) of Pampa
del Indio, northeastern Argentina, and used wing geometric morphometry to compare
pre-spray and post-spray (re-infestant bugs) Triatoma infestans
populations. The community-wide spraying with pyrethroids reduced the prevalence of
house infestation by T. infestans from 31.9% to < 1% during a
four-year follow-up, unlike our previous studies in the neighbouring Area I. Two
groups of bug collection sites differing in wing shape variables before interventions
(including 221 adults from 11 domiciles) were used as a reference for assigning 44
post-spray adults. Wing shape variables from post-spray, high-density bug colonies
and pre-spray groups were significantly different, suggesting that re-infestant
insects had an external origin. Insects from one house differed strongly in wing
shape variables from all other specimens. A further comparison between insects from
both areas supported the existence of independent re-infestation processes within the
same district. These results point to local heterogeneities in house re-infestation
dynamics and emphasise the need to expand the geographic coverage of vector
surveillance and control operations to the affected region.
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Affiliation(s)
- María Sol Gaspe
- Instituto de Ecología, Genética y Evolución, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Yael Mariana Provecho
- Instituto de Ecología, Genética y Evolución, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Romina Valeria Piccinali
- Instituto de Ecología, Genética y Evolución, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ricardo Esteban Gürtler
- Instituto de Ecología, Genética y Evolución, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Buenos Aires, Argentina
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Salvatella R, Irabedra P, Castellanos LG. Interruption of vector transmission by native vectors and "the art of the possible". Mem Inst Oswaldo Cruz 2015; 109:122-5. [PMID: 24626310 PMCID: PMC4005527 DOI: 10.1590/0074-0276140338] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 09/26/2013] [Indexed: 11/22/2022] Open
Abstract
In a recent article in the Reader’s Opinion, advantages and disadvantages of the
certification processes of interrupted Chagas disease transmission (American
trypanosomiasis) by native vector were discussed. Such concept, accepted by those
authors for the case of endemic situations with introduced vectors, has been built on
a long and laborious process by endemic countries and Subregional Initiatives for
Prevention, Control and Treatment of Chagas, with Technical Secretariat of the Pan
American Health Organization/World Health Organization, to create a horizon target
and goal to concentrate priorities and resource allocation and actions. With varying
degrees of sucess, which are not replaceable for a certificate of good practice, has
allowed during 23 years to safeguard the effective control of transmission of
Trypanosoma cruzi not to hundreds of thousands, but millions of people at risk
conditions, truly “the art of the possible.”
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Affiliation(s)
- Roberto Salvatella
- Communicable Diseases and Health Analysis Department, Neglected, Tropical and Vector Borne Diseases Unit, WashingtonDC, USA, Communicable Diseases and Health Analysis Department , Neglected, Tropical and Vector Borne Diseases Unit , Washington DC , USA
| | - Pilar Irabedra
- Communicable Diseases and Health Analysis Department, Neglected, Tropical and Vector Borne Diseases Unit, WashingtonDC, USA, Communicable Diseases and Health Analysis Department , Neglected, Tropical and Vector Borne Diseases Unit , Washington DC , USA
| | - Luis G Castellanos
- Communicable Diseases and Health Analysis Department, Neglected, Tropical and Vector Borne Diseases Unit, WashingtonDC, USA, Communicable Diseases and Health Analysis Department , Neglected, Tropical and Vector Borne Diseases Unit , Washington DC , USA
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Coura JR. Chagas disease: control, elimination and eradication. Is it possible? Mem Inst Oswaldo Cruz 2015; 108:962-7. [PMID: 24402148 PMCID: PMC4005548 DOI: 10.1590/0074-0276130565] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 12/09/2013] [Indexed: 12/02/2022] Open
Abstract
From an epidemiological point of view, Chagas disease and its reservoirs and vectors
can present the following characteristics: (i) enzooty, maintained by wild animals
and vectors, with broad occurrence from southern United States of America (USA) to
southern Argentina and Chile (42ºN 49ºS), (ii) anthropozoonosis, when man invades the
wild ecotope and becomes infected with Trypanosoma cruzi from wild
animals or vectors or when the vectors and wild animals, especially marsupials,
invade the human domicile and infect man, (iii) zoonosis-amphixenosis and exchanged
infection between animals and humans by domestic vectors in endemic areas and (iv)
zooanthroponosis, infection that is transmitted from man to animals, by means of
domestic vectors, which is the rarest situation in areas endemic for Chagas disease.
The characteristics of Chagas disease as an enzooty of wild animals and as an
anthropozoonosis are seen most frequently in the Brazilian Amazon and in the
Pan-Amazon region as a whole, where there are 33 species of six genera of wild
animals: Marsupialia, Chiroptera, Rodentia, Edentata (Xenarthra), Carnivora and
Primata and 27 species of triatomines, most of which infected with T.
cruzi . These conditions place the resident populations of this area or
its visitors - tourists, hunters, fishermen and especially the people whose
livelihood involves plant extraction - at risk of being affected by Chagas disease.
On the other hand, there has been an exponential increase in the acute cases of
Chagas disease in that region through oral transmission of T. cruzi
, causing outbreaks of the disease. In four seroepidemiological surveys that were
carried out in areas of the microregion of the Negro River, state of Amazonas, in
1991, 1993, 1997 and 2010, we found large numbers of people who were serologically
positive for T. cruzi infection. The majority of them and/or their
relatives worked in piassava extraction and had come into contact with and were stung
by wild triatomines in that area. Finally, a characteristic that is greatly in
evidence currently is the migration of people with Chagas disease from endemic areas
of Latin America to non-endemic countries. This has created a new dilemma for these
countries: the risk of transmission through blood transfusion and the onus of
controlling donors and treating migrants with the disease. As an enzooty of wild
animals and vectors, and as an anthropozoonosis, Chagas disease cannot be eradicated,
but it must be controlled by transmission elimination to man.
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Sangenis LHC, Saraiva RM, Georg I, de Castro L, dos Santos Lima V, Roque ALR, Xavier SCDC, Santos LC, Fernandes FA, Sarquis O, Lima MM, Carvalho-Costa FA, Bóia MN. Autochthonous transmission of Chagas disease in Rio de Janeiro State, Brazil: a clinical and eco-epidemiological study. BMC Infect Dis 2015; 15:4. [PMID: 25566786 PMCID: PMC4297387 DOI: 10.1186/s12879-014-0732-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Accepted: 12/19/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND After the control of the main modes of Chagas disease (CD) transmission in most endemic countries, it is important to identify the participation of native sylvatic vectors in CD transmission. Although CD is not considered endemic in Rio de Janeiro State (RJ), Brazil, we identified patients with CD born in RJ and investigated the possible autochthonous transmission in the state. METHODS Patients born in RJ and followed in our institution between 1986 and 2011 were retrospectively analyzed. The cases identified as autochthonous transmission were submitted to epidemiological, clinical, serological, parasitological and molecular studies. Sectional field study with serological survey, research of sylvatic reservoirs and vectors was conducted in rural areas where patients were born. RESULTS Among 1963 patients, 69 (3.5%) were born in RJ. From these, 15 (21.7%) were considered to have acquired the infection by autochthonous transmission. Cardiac form was the commonest form of presentation (60%). In rural areas in RJ northern region, sylvatic cycles of Trypanosoma cruzi and domestic invasion by Triatoma vitticeps were identified, and CD prevalence among inhabitants was 0.74%.TcI genotype was identified in sylvatic reservoirs and vectors. The genotype (mixed infection TcI/TcVI) could be identified in one of the autochthonous cases. CONCLUSIONS The autochthonous vectorial transmission of CD occurs in RJ, probably due to wild cycles of T. cruzi and sylvatic vectors, such as T. vitticeps. Therefore, the health authorities should evaluate if RJ should be included in the original endemic area of CD and CD should be included in the diagnostic work out of cardiomyopathy of patients born in RJ. Moreover, control and educational measures should be put into place in the risk areas.
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Affiliation(s)
- Luiz Henrique Conde Sangenis
- Laboratório de Pesquisa Clínica em Doença de Chagas, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
| | - Roberto Magalhães Saraiva
- Laboratório de Pesquisa Clínica em Doença de Chagas, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
| | - Ingebourg Georg
- Laboratório de Imunodiagnóstico, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Liane de Castro
- Laboratório de Farmacocinética, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Valdirene dos Santos Lima
- Laboratório de Biologia de Tripanossomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - André Luiz R Roque
- Laboratório de Biologia de Tripanossomatídeos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | | | - Laura Cristina Santos
- Laboratório de Doenças Parasitárias, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Fabiano A Fernandes
- Laboratório de Ecoepidemiologia da Doença de Chagas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Otília Sarquis
- Laboratório de Ecoepidemiologia da Doença de Chagas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Marli Maria Lima
- Laboratório de Ecoepidemiologia da Doença de Chagas, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | | | - Márcio Neves Bóia
- Laboratório de Biologia e Parasitologia de Mamíferos Silvestres Reservatórios, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
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Coura JR, Viñas PA, Junqueira ACV. Ecoepidemiology, short history and control of Chagas disease in the endemic countries and the new challenge for non-endemic countries. Mem Inst Oswaldo Cruz 2014; 109:856-62. [PMID: 25410988 PMCID: PMC4296489 DOI: 10.1590/0074-0276140236] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 08/29/2014] [Indexed: 11/23/2022] Open
Abstract
Chagas disease is maintained in nature through the interchange of three cycles: the wild, peridomestic and domestic cycles. The wild cycle, which is enzootic, has existed for millions of years maintained between triatomines and wild mammals. Human infection was only detected in mummies from 4,000-9,000 years ago, before the discovery of the disease by Carlos Chagas in 1909. With the beginning of deforestation in the Americas, two-three centuries ago for the expansion of agriculture and livestock rearing, wild mammals, which had been the food source for triatomines, were removed and new food sources started to appear in peridomestic areas: chicken coops, corrals and pigsties. Some accidental human cases could also have occurred prior to the triatomines in peridomestic areas. Thus, triatomines progressively penetrated households and formed the domestic cycle of Chagas disease. A new epidemiological, economic and social problem has been created through the globalisation of Chagas disease, due to legal and illegal migration of individuals infected by Trypanosoma cruzi or presenting Chagas disease in its varied clinical forms, from endemic countries in Latin America to non-endemic countries in North America, Europe, Asia and Oceania, particularly to the United States of America and Spain. The main objective of the present paper was to present a general view of the interchanges between the wild, peridomestic and domestic cycles of the disease, the development of T. cruzi among triatomine, their domiciliation and control initiatives, the characteristics of the disease in countries in the Americas and the problem of migration to non-endemic countries.
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Affiliation(s)
- José Rodrigues Coura
- Laboratório de Doenças Parasitárias, Instituto Oswaldo Cruz-Fiocruz,
Rio de Janeiro, RJ, Brasil
| | - Pedro Albajar Viñas
- Neglected Tropical Diseases, Chagas Disease Programme, World Health
Organization, Geneve, Switzerland
| | - Angela CV Junqueira
- Laboratório de Doenças Parasitárias, Instituto Oswaldo Cruz-Fiocruz,
Rio de Janeiro, RJ, Brasil
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Tarleton RL, Gürtler RE, Urbina JA, Ramsey J, Viotti R. Chagas disease and the london declaration on neglected tropical diseases. PLoS Negl Trop Dis 2014; 8:e3219. [PMID: 25299701 PMCID: PMC4191937 DOI: 10.1371/journal.pntd.0003219] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Rick L. Tarleton
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- The Chagas Disease Foundation, Bogart, Georgia, United States of America
- * E-mail:
| | - Ricardo E. Gürtler
- Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Julio A. Urbina
- Venezuelan Institute for Scientific Research, Caracas, Venezuela
| | - Janine Ramsey
- Centro Regional de Investigación en Salud Pública, Instituto Nacional de Salud Pública, Tapachula, Chiapas, México
| | - Rodolfo Viotti
- Hospital Interzonal General de Agudos (HIGA) Eva Perón, Sección Chagas, Servicio de Cardiología, Buenos Aires, Argentina
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Gürtler RE, Cecere MC, Fernández MDP, Vazquez-Prokopec GM, Ceballos LA, Gurevitz JM, Kitron U, Cohen JE. Key source habitats and potential dispersal of triatoma infestans populations in Northwestern Argentina: implications for vector control. PLoS Negl Trop Dis 2014; 8:e3238. [PMID: 25299653 PMCID: PMC4191936 DOI: 10.1371/journal.pntd.0003238] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 09/04/2014] [Indexed: 11/18/2022] Open
Abstract
Background Triatoma infestans —the principal vector of the infection that causes Chagas disease— defies elimination efforts in the Gran Chaco region. This study identifies the types of human-made or -used structures that are key sources of these bugs in the initial stages of house reinfestation after an insecticide spraying campaign. Methodology and Principal Findings We measured demographic and blood-feeding parameters at two geographic scales in 11 rural communities in Figueroa, northwest Argentina. Of 1,297 sites searched in spring, 279 (21.5%) were infested. Bug abundance per site and female fecundity differed significantly among habitat types (ecotopes) and were highly aggregated. Domiciles (human sleeping quarters) had maximum infestation prevalence (38.7%), human-feeding bugs and total egg production, with submaximal values for other demographic and blood-feeding attributes. Taken collectively peridomestic sites were three times more often infested than domiciles. Chicken coops had greater bug abundance, blood-feeding rates, engorgement status, and female fecundity than pig and goat corrals. The host-feeding patterns were spatially structured yet there was strong evidence of active dispersal of late-stage bugs between ecotopes. Two flight indices predicted that female fliers were more likely to originate from kitchens and domiciles, rejecting our initial hypothesis that goat and pig corrals would dominate. Conclusions and Significance Chicken coops and domiciles were key source habitats fueling rapid house reinfestation. Focusing control efforts on ecotopes with human-fed bugs (domiciles, storerooms, goat corrals) would neither eliminate the substantial contributions to bug population growth from kitchens, chicken coops, and pig corrals nor stop dispersal of adult female bugs from kitchens. Rather, comprehensive control of the linked network of ecotopes is required to prevent feeding on humans, bug population growth, and bug dispersal simultaneously. Our study illustrates a demographic approach that may be applied to other regions and triatomine species for the design of innovative, improved vector control strategies. The major vectors of Chagas disease are species of triatomine bugs adapted to human sleeping quarters and peridomestic annexes where they feed on humans and domestic or synanthropic mammals or birds. Knowledge of the demography and nutritional status of Triatominae in real-life settings is still fragmentary, and this affects our ability to prevent or reduce house reinfestation after insecticide spraying. In addition to showing where the bugs are likely to live (occupancy and density information), our observations and analysis of flight dispersal provide insights into where bugs are likely to originate. Data on nymphal and adult sex ratios, nutritional status, and female fecundity point to the key ecotopes and sites driving the population growth of the bugs and fueling house reinfestation. Focusing control efforts on the three ecotopes (human sleeping quarters, storerooms, and goat corrals) that housed reactive, human-fed bugs would neither eliminate the substantial contributions to bug population growth from kitchens, chicken coops, and pig corrals nor stop dispersal of adult female bugs from kitchens. Rather, comprehensive control of the linked network of ecotopes in a typical house compound and community is required to prevent feeding on humans, bug population growth, and bug dispersal simultaneously.
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Affiliation(s)
- Ricardo E. Gürtler
- Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina
- * E-mail:
| | - María C. Cecere
- Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina
| | - María del Pilar Fernández
- Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina
| | - Gonzalo M. Vazquez-Prokopec
- Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina
- Department of Environmental Studies, Emory University, Atlanta, Georgia, United States of America
| | - Leonardo A. Ceballos
- Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina
| | - Juan M. Gurevitz
- Laboratory of Eco-Epidemiology, Department of Ecology, Genetics and Evolution, Universidad de Buenos Aires-IEGEBA (CONICET-UBA), Buenos Aires, Argentina
| | - Uriel Kitron
- Department of Environmental Studies, Emory University, Atlanta, Georgia, United States of America
| | - Joel E. Cohen
- Laboratory of Populations, Rockefeller and Columbia Universities, New York, New York, United States of America
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Abad-Franch F, Valença-Barbosa C, Sarquis O, Lima MM. All that glisters is not gold: sampling-process uncertainty in disease-vector surveys with false-negative and false-positive detections. PLoS Negl Trop Dis 2014; 8:e3187. [PMID: 25233352 PMCID: PMC4169387 DOI: 10.1371/journal.pntd.0003187] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 08/14/2014] [Indexed: 11/06/2022] Open
Abstract
Background Vector-borne diseases are major public health concerns worldwide. For many of them, vector control is still key to primary prevention, with control actions planned and evaluated using vector occurrence records. Yet vectors can be difficult to detect, and vector occurrence indices will be biased whenever spurious detection/non-detection records arise during surveys. Here, we investigate the process of Chagas disease vector detection, assessing the performance of the surveillance method used in most control programs – active triatomine-bug searches by trained health agents. Methodology/Principal Findings Control agents conducted triplicate vector searches in 414 man-made ecotopes of two rural localities. Ecotope-specific ‘detection histories’ (vectors or their traces detected or not in each individual search) were analyzed using ordinary methods that disregard detection failures and multiple detection-state site-occupancy models that accommodate false-negative and false-positive detections. Mean (±SE) vector-search sensitivity was ∼0.283±0.057. Vector-detection odds increased as bug colonies grew denser, and were lower in houses than in most peridomestic structures, particularly woodpiles. False-positive detections (non-vector fecal streaks misidentified as signs of vector presence) occurred with probability ∼0.011±0.008. The model-averaged estimate of infestation (44.5±6.4%) was ∼2.4–3.9 times higher than naïve indices computed assuming perfect detection after single vector searches (11.4–18.8%); about 106–137 infestation foci went undetected during such standard searches. Conclusions/Significance We illustrate a relatively straightforward approach to addressing vector detection uncertainty under realistic field survey conditions. Standard vector searches had low sensitivity except in certain singular circumstances. Our findings suggest that many infestation foci may go undetected during routine surveys, especially when vector density is low. Undetected foci can cause control failures and induce bias in entomological indices; this may confound disease risk assessment and mislead program managers into flawed decision making. By helping correct bias in naïve indices, the approach we illustrate has potential to critically strengthen vector-borne disease control-surveillance systems. Vector-borne disease prevention often relies on health agents inspecting dwellings and eliminating the vector infestation foci they detect. The effectiveness of prevention programs thus depends on vector-detection performance. Unfortunately, detection failures can be common, particularly when infestation is rare and vector foci small. Although this can threaten vector control, the actual performance of vector searches has seldom been investigated in detail. Here, we assess Chagas disease vector detection by trained control-surveillance agents. We used models that explicitly account for detection errors to analyze triplicate vector detection/non-detection records from 414 man-made ‘ecotopes’ (houses, henhouses, woodpiles, etc.) in two rural localities. On average, a single round of vector searches correctly identified about 28% of the infested ecotopes; detection was more challenging in lightly-infested ecotopes and in some ecotope types, particularly houses and brick piles. After correcting detection errors, we estimated that ∼45% of the ecotopes were most likely infested, while observed rates were ∼11–19%; standard, single-round vector searches therefore missed many infestation foci. Our findings underscore the importance of taking detection failures into account when assessing infestation by disease vectors, and illustrate a straightforward approach to tackle the major but still underappreciated problem of imperfect vector detection.
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Affiliation(s)
- Fernando Abad-Franch
- Infectious Disease Ecology Laboratory, Instituto Leônidas e Maria Deane – Fiocruz Amazônia, Manaus, Brazil
- * E-mail: ;
| | - Carolina Valença-Barbosa
- Chagas Disease Eco-epidemiology Laboratory, Instituto Oswaldo Cruz – Fiocruz, Rio de Janeiro, Brazil
| | - Otília Sarquis
- Chagas Disease Eco-epidemiology Laboratory, Instituto Oswaldo Cruz – Fiocruz, Rio de Janeiro, Brazil
| | - Marli M. Lima
- Chagas Disease Eco-epidemiology Laboratory, Instituto Oswaldo Cruz – Fiocruz, Rio de Janeiro, Brazil
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Vinhaes MC, de Oliveira SV, Reis PO, de Lacerda Sousa AC, Silva RAE, Obara MT, Bezerra CM, da Costa VM, Alves RV, Gurgel-Gonçalves R. Assessing the vulnerability of Brazilian municipalities to the vectorial transmission of Trypanosoma cruzi using multi-criteria decision analysis. Acta Trop 2014; 137:105-10. [PMID: 24857942 DOI: 10.1016/j.actatropica.2014.05.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Revised: 05/11/2014] [Accepted: 05/14/2014] [Indexed: 11/24/2022]
Abstract
Despite the dramatic reduction in Trypanosoma cruzi vectorial transmission in Brazil, acute cases of Chagas disease (CD) continue to be recorded. The identification of areas with greater vulnerability to the occurrence of vector-borne CD is essential to prevention, control, and surveillance activities. In the current study, data on the occurrence of domiciliated triatomines in Brazil (non-Amazonian regions) between 2007 and 2011 were analyzed. Municipalities' vulnerability was assessed based on socioeconomic, demographic, entomological, and environmental indicators using multi-criteria decision analysis (MCDA). Overall, 2275 municipalities were positive for at least one of the six triatomine species analyzed (Panstrongylus megistus, Triatoma infestans, Triatoma brasiliensis, Triatoma pseudomaculata, Triatoma rubrovaria, and Triatoma sordida). The municipalities that were most vulnerable to vector-borne CD were mainly in the northeast region and exhibited a higher occurrence of domiciliated triatomines, lower socioeconomic levels, and more extensive anthropized areas. Most of the 39 new vector-borne CD cases confirmed between 2001 and 2012 in non-Amazonian regions occurred within the more vulnerable municipalities. Thus, MCDA can help to identify the states and municipalities that are most vulnerable to the transmission of T. cruzi by domiciliated triatomines, which is critical for directing adequate surveillance, prevention, and control activities. The methodological approach and results presented here can be used to enhance CD surveillance in Brazil.
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Carneiro ZA, da S. Maia PI, Sesti-Costa R, Lopes CD, Pereira TA, Milanezi CM, da Silva MAP, Lopez RFV, Silva JS, Deflon VM. In vitro and in vivo trypanocidal activity of H2bdtc-loaded solid lipid nanoparticles. PLoS Negl Trop Dis 2014; 8:e2847. [PMID: 24810753 PMCID: PMC4014426 DOI: 10.1371/journal.pntd.0002847] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 03/25/2014] [Indexed: 01/24/2023] Open
Abstract
The parasite Trypanosoma cruzi causes Chagas disease, which remains a serious public health concern and continues to victimize thousands of people, primarily in the poorest regions of Latin America. In the search for new therapeutic drugs against T. cruzi, here we have evaluated both the in vitro and the in vivo activity of 5-hydroxy-3-methyl-5-phenyl-pyrazoline-1-(S-benzyl dithiocarbazate) (H2bdtc) as a free compound or encapsulated into solid lipid nanoparticles (SLN); we compared the results with those achieved by using the currently employed drug, benznidazole. H2bdtc encapsulated into solid lipid nanoparticles (a) effectively reduced parasitemia in mice at concentrations 100 times lower than that normally employed for benznidazole (clinically applied at a concentration of 400 µmol kg(-1) day(-1)); (b) diminished inflammation and lesions of the liver and heart; and (c) resulted in 100% survival of mice infected with T. cruzi. Therefore, H2bdtc is a potent trypanocidal agent.
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Affiliation(s)
- Zumira A. Carneiro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Pedro I. da S. Maia
- Instituto de Química de São Carlos, University of São Paulo, São Carlos, São Paulo, Brazil
| | - Renata Sesti-Costa
- Departamento de Bioquímica e Imunologia, School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Carla D. Lopes
- Departamento de Bioquímica e Imunologia, School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Tatiana A. Pereira
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Cristiane M. Milanezi
- Departamento de Bioquímica e Imunologia, School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Marcelo A. Pereira. da Silva
- Instituto de Física de São Carlos, University of São Paulo, São Carlos, São Paulo, Brazil
- Centro Universitário Central Paulista - UNICEP, São Carlos, São Paulo, Brazil
| | - Renata F. V. Lopez
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - João S. Silva
- Departamento de Bioquímica e Imunologia, School of Medicine, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Victor M. Deflon
- Instituto de Química de São Carlos, University of São Paulo, São Carlos, São Paulo, Brazil
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Xavier SCDC, Roque ALR, Bilac D, de Araújo VAL, Neto SFDC, Lorosa ES, da Silva LFCF, Jansen AM. Distantiae transmission of Trypanosoma cruzi: a new epidemiological feature of acute Chagas disease in Brazil. PLoS Negl Trop Dis 2014; 8:e2878. [PMID: 24854494 PMCID: PMC4031066 DOI: 10.1371/journal.pntd.0002878] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 04/04/2014] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The new epidemiological scenario of orally transmitted Chagas disease that has emerged in Brazil, and mainly in the Amazon region, needs to be addressed with a new and systematic focus. Belém, the capital of Pará state, reports the highest number of acute Chagas disease (ACD) cases associated with the consumption of açaí juice. METHODOLOGY/PRINCIPAL FINDINGS The wild and domestic enzootic transmission cycles of Trypanosoma cruzi were evaluated in the two locations (Jurunas and Val-de Cães) that report the majority of the autochthonous cases of ACD in Belém city. Moreover, we evaluated the enzootic cycle on the three islands that provide most of the açaí fruit that is consumed in these localities. We employed parasitological and serological tests throughout to evaluate infectivity competence and exposure to T. cruzi. In Val-de-Cães, no wild mammal presented positive parasitological tests, and 56% seroprevalence was observed, with low serological titers. Three of 14 triatomines were found to be infected (TcI). This unexpected epidemiological picture does not explain the high number of autochthonous ACD cases. In Jurunas, the cases of ACD could not be autochthonous because of the absence of any enzootic cycle of T. cruzi. In contrast, in the 3 island areas from which the açaí fruit originates, 66.7% of wild mammals and two dogs displayed positive hemocultures, and 15.6% of triatomines were found to be infected by T. cruzi. Genotyping by mini-exon gene and PCR-RFLP (1f8/Akw21I) targeting revealed that the mammals and triatomines from the islands harbored TcI and Trypanosoma rangeli in single and mixed infections. CONCLUSION/SIGNIFICANCE These findings show that cases of Chagas disease in the urban area of Belém may be derived from infected triatomines coming together with the açaí fruits from distant islands. We term this new epidemiological feature of Chagas disease as "Distantiae transmission".
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Affiliation(s)
| | - André Luiz Rodrigues Roque
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Daniele Bilac
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Sócrates Fraga da Costa Neto
- Laboratory of Biology and Parasitology of Wild Reservoir Mammals, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Elias Seixas Lorosa
- International and National Laboratory of Reference for Triatominae Taxonomy, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Ana Maria Jansen
- Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil
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Espinoza N, Borrás R, Abad-Franch F. Chagas disease vector control in a hyperendemic setting: the first 11 years of intervention in Cochabamba, Bolivia. PLoS Negl Trop Dis 2014; 8:e2782. [PMID: 24699407 PMCID: PMC3974664 DOI: 10.1371/journal.pntd.0002782] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 02/24/2014] [Indexed: 11/25/2022] Open
Abstract
Background Chagas disease has historically been hyperendemic in the Bolivian Department of Cochabamba. In the early 2000s, an extensive vector control program was implemented; 1.34 million dwelling inspections were conducted to ascertain infestation (2000–2001/2003–2011), with blanket insecticide spraying in 2003–2005 and subsequent survey-spraying cycles targeting residual infestation foci. Here, we assess the effects of this program on dwelling infestation rates (DIRs). Methodology/Principal Findings Program records were used to calculate annual, municipality-level aggregate DIRs (39 municipalities); very high values in 2000–2001 (median: 0.77–0.69) dropped to ∼0.03 from 2004 on. A linear mixed model (with municipality as a random factor) suggested that infestation odds decreased, on average, by ∼28% (95% confidence interval [CI95] 6–44%) with each 10-fold increase in control effort. A second, better-fitting mixed model including year as an ordinal predictor disclosed large DIR reductions in 2001–2003 (odds ratio [OR] 0.11, CI95 0.06–0.19) and 2003–2004 (OR 0.22, CI95 0.14–0.34). Except for a moderate decrease in 2005–2006, no significant changes were detected afterwards. In both models, municipality-level DIRs correlated positively with previous-year DIRs and with the extent of municipal territory originally covered by montane dry forests. Conclusions/Significance Insecticide-spraying campaigns had very strong, long-lasting effects on DIRs in Cochabamba. However, post-intervention surveys consistently detected infestation in ∼3% of dwellings, underscoring the need for continuous surveillance; higher DIRs were recorded in the capital city and, more generally, in municipalities dominated by montane dry forest – an eco-region where wild Triatoma infestans are widespread. Traditional strategies combining insecticide spraying and longitudinal surveillance are thus confirmed as very effective means for area-wide Chagas disease vector control; they will be particularly beneficial in highly-endemic settings, but should also be implemented or maintained in other parts of Latin America where domestic infestation by triatomines is still commonplace. Chagas disease is among the most serious public health problems in Latin America; the highest prevalence of infection by its causative agent, the parasite Trypanosoma cruzi, has historically been recorded in some parts of Bolivia. In the early 2000s, a massive insecticide-spraying program was set up to control dwelling infestation by the blood-sucking bugs that transmit the disease. Here we provide a detailed assessment of the effects of this program in the Department of Cochabamba, one of the most highly-endemic settings worldwide. Our analyses show that municipality-level dwelling infestation rates plummeted from over 70–80% in 2001–2003 to about 2–3% in 2004–2011. This residual infestation was higher in the capital city and, more generally, in municipalities where montane dry forests dominate – probably because wild populations of the main vector, Triatoma infestans, are common in that eco-region. Despite the impressive early achievements of the program, with about 0.5 million people protected from contagion, sustained disease control will require fully operational long-term surveillance systems.
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Affiliation(s)
- Natalisisy Espinoza
- Departamento de Microbiología y Ecología, Facultad de Medicina y Odontología, Universitat de València, Valencia, Spain
| | - Rafael Borrás
- Departamento de Microbiología y Ecología, Facultad de Medicina y Odontología, Universitat de València, Valencia, Spain
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Martins-Melo FR, Ramos AN, Alencar CH, Heukelbach J. Prevalence of Chagas disease in Brazil: a systematic review and meta-analysis. Acta Trop 2014; 130:167-74. [PMID: 24139912 DOI: 10.1016/j.actatropica.2013.10.002] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 08/30/2013] [Accepted: 10/01/2013] [Indexed: 12/14/2022]
Abstract
Chagas disease is a major public health problem in Brazil and Latin America. During the last years, it has become an emerging problem in North America and Europe due to increasing international migration. Here we describe the prevalence of Chagas disease in Brazil through a systematic review. We searched national and international electronic databases, grey literature and reference lists of selected articles for population-based studies on Chagas disease prevalence in Brazil, performed from 1980 until September 2012. Forty-two articles with relevant prevalence data were identified from a total of 4985 references. Prevalence ranged from 0% to 25.1%. Most surveys were performed in the Northeast region, especially in the state of Piauí. We observed a high degree of heterogeneity in most pooled estimates (I(2)>75%; p<0.001). The pooled estimate of Chagas disease prevalence across studies for the entire period was 4.2% (95% CI: 3.1-5.7), ranging from 4.4% (95% CI: 2.3-8.3) in the 1980s to 2.4% (95% CI: 1.5-3.8) after 2000. Females (4.2%; 95% CI: 2.6-6.8), >60 year-olds (17.7%; 95% CI: 11.4-26.5), Northeast (5.0%; 95% CI: 3.1-8.1) and Southeast (5.0%; CI: 2.4-9.9) regions and mixed (urban/rural) areas (6.4%; 95% CI: 4.2-9.4) had the highest pooled prevalence. About 4.6 million (95% CI: 2.9-7.2 million) of people are estimated to be infected with Trypanosoma cruzi. The small number of studies and small-scale samples of the general population in some areas limit interpretation, and findings of this review do not necessarily reflect the situation of the entire country. Systematic population-based studies at regional and national level are recommended to provide more accurate estimates and better define the epidemiology and risk areas of Chagas disease in Brazil.
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Affiliation(s)
| | - Alberto Novaes Ramos
- Department of Community Health, School of Medicine, Federal University of Ceará, 60430-140 Fortaleza, Brazil
| | - Carlos Henrique Alencar
- Department of Community Health, School of Medicine, Federal University of Ceará, 60430-140 Fortaleza, Brazil
| | - Jorg Heukelbach
- Department of Community Health, School of Medicine, Federal University of Ceará, 60430-140 Fortaleza, Brazil; Anton Breinl Centre for Public Health and Tropical Medicine, School of Public Health, Tropical Medicine and Rehabilitation Sciences, James Cook University, Townsville, QLD 4811, Australia.
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Carvalho DB, Almeida CE, Rocha CS, Gardim S, Mendonça VJ, Ribeiro AR, Alves ZC, Ruellas KT, Vedoveli A, da Rosa JA. A novel association between Rhodnius neglectus and the Livistona australis palm tree in an urban center foreshadowing the risk of Chagas disease transmission by vectorial invasions in Monte Alto City, São Paulo, Brazil. Acta Trop 2014; 130:35-8. [PMID: 24145156 DOI: 10.1016/j.actatropica.2013.10.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 10/02/2013] [Accepted: 10/09/2013] [Indexed: 10/26/2022]
Abstract
After several public notifications of domiciliary invasions, palm trees were investigated in downtown Monte Alto City, São Paulo State, Brazil, in proximity to the city hall building, the main church, condominiums and marketing establishments. One hundred seventy four palm trees of 10 species were investigated, in which 72 specimens of Rhodnius neglectus, a potential Chagas disease vector, were captured via manual methods. All insects were collected from dead leaves, organic debris and bird nests in the only three Livistona australis palm trees in the central park square. This was the first record of R. neglectus colonizing this palm species. Although no Trypanosoma cruzi was found by abdominal compression followed by light microscopy, the poor nutritional status of the bugs hampered the examination of gut contents for parasite detection. Furthermore, the central crowns of the trees, which shelter bats (Chiroptera: Mammalia), could not be carefully searched for insects due to difficult access. This new finding highlights the sudden alteration in insect behavior, probably as a result of man's interference. This report aims to warn those involved in the health system about this new threat, justifying detailed research of the area to evaluate the magnitude of this emerging public health issue.
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Pereira PCM, Navarro EC. Challenges and perspectives of Chagas disease: a review. J Venom Anim Toxins Incl Trop Dis 2013; 19:34. [PMID: 24354455 PMCID: PMC3898031 DOI: 10.1186/1678-9199-19-34] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 12/05/2013] [Indexed: 01/30/2023] Open
Abstract
Chagas disease (CD), also known as American trypanosomiasis, is caused by the flagellated protozoan Trypanosoma cruzi, and affects an estimated 8 to 10 million people worldwide. In Latin America, 25 million people live in risk areas, while in 2008 alone, 10,000 CD-related deaths were reported. This review aimed to evaluate the challenges of CD control, future perspectives, and actions performed worldwide to control expansion of the disease and its impact on public health in Latin America.
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Affiliation(s)
- Paulo Câmara Marques Pereira
- Department of Tropical Diseases, Botucatu Medical School, São Paulo State University (UNESP - Univ Estadual Paulista), Av, Prof, Montenegro, Distrito de Rubião Junior, Botucatu, São Paulo State, Brazil.
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Brenière SF, Salas R, Buitrago R, Brémond P, Sosa V, Bosseno MF, Waleckx E, Depickère S, Barnabé C. Wild populations of Triatoma infestans are highly connected to intra-peridomestic conspecific populations in the Bolivian Andes. PLoS One 2013; 8:e80786. [PMID: 24278320 PMCID: PMC3835561 DOI: 10.1371/journal.pone.0080786] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 10/07/2013] [Indexed: 11/25/2022] Open
Abstract
Triatoma infestans, the major vector of Chagas disease south of the Amazon in South America, has a large distribution of wild populations, contrary to what has previously been stated. These populations have been suspected of being the source of reinfestation of human habitats and could impede the full success of vector control campaigns. This study examined gene flow between intra-peridomestic populations and wild populations collected in the surround areas in three Andean localities in Bolivia. The populations were defined according to temporal, ecological, and spatial criteria. After DNA extraction from the legs of each insect, the samples were analyzed using seven microsatellite markers. First, the analysis of molecular variance (AMOVA) detected an absence of differentiation between wild and intra-peridomestic populations, although strong structuring was observed between the populations within each environment. Then for some populations, the Bayesian method of assignment to inferred populations showed very similar assignment patterns of the members of wild or intra-peridomestic populations in each locality. Finally, the detection of the first-generation migrants within the different populations provided evidence of insect displacement from the wild to the intra-peridomestic environment. This result indicates that, after control campaigns in the Andes, controlling this new paradigm of vector transmission risk stemming from the invasion of human habitats by wild populations of T. infestans requires long-term maintenance of public monitoring to keep the risk at a minimal level. Since wild populations of T. infestans have also been detected elsewhere in Argentina, Paraguay, and Chile, there is an urgent need to take these populations into account in future monitoring of Chagas disease transmission.
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Affiliation(s)
- Simone Frédérique Brenière
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, La Paz, Bolivia
- * E-mail:
| | - Renata Salas
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, La Paz, Bolivia
| | - Rosio Buitrago
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, La Paz, Bolivia
| | - Philippe Brémond
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
| | - Victor Sosa
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Instituto de Investigaciones Biomédicas y de Interacción Social (IIBISMED), Facultad de Medicina, Universidad Mayor de San Simón, Cochabamba, Bolivia
| | - Marie-France Bosseno
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, La Paz, Bolivia
| | - Etienne Waleckx
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Laboratorio de Parasitología, Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Mérida, Yucatán, México
| | - Stéphanie Depickère
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, La Paz, Bolivia
| | - Christian Barnabé
- Health Department, MIVEGEC (Université de Montpellier 1 et 2, CNRS 5290, IRD 224), Maladies Infectieuses et Vecteurs : Ecologie, Génétique, Evolution et Contrôle, Institut de recherche pour le développement (IRD), Montpellier, France
- Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, La Paz, Bolivia
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