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Meraz-Medina T, Rúa-Vázquez PD, Montealegre-Bautista JF, Martínez-Ibarra JA. Infection with Trypanosoma Cruzi Chagas and Characterization of Human Habitats of Triatoma Picturata (Usinger) in Western Mexico. JOURNAL OF VECTOR ECOLOGY : JOURNAL OF THE SOCIETY FOR VECTOR ECOLOGY 2023; 48:66-71. [PMID: 37843448 DOI: 10.52707/1081-1710-48.2.66] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 06/02/2023] [Indexed: 10/17/2023]
Abstract
Chagas disease is one of the most important vector-borne diseases in Latin America. Triatoma picturata (Usinger), distributed in western Mexico, is one of the most important vectors of Trypanosoma cruzi Chagas. Knowing the type and materials used for building homes could lead to improved methods for controlling triatomines by focusing efforts on controlling every species of triatomine in its specific microhabitat. Houses in three studied localities of western Mexico that harbored T. picturata were characterized, as well as two entomological indices. Infestation Index values varied from 10.8% to 51.9% in the three localities, whereas Natural Infection Index values varied from 18.1% to 35.2%. Characteristics of houses invaded by T. picturata also varied. In Juan Gil Preciado, with the highest Entomological Index values, most houses were built of adobe walls with a roof of clay tiles and a dirt floor, and included the presence of domestic animals. Our data indicate that the potential risk of infection with T. cruzi differs markedly for inhabitants of the three studied localities, which demonstrates the importance of studying local populations of triatomines. Our study should contribute to decision-making regarding triatomine control efforts by providing profiles of houses that are more susceptible to triatomine invasion.
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Affiliation(s)
- Tzintli Meraz-Medina
- Laboratorio de Entomología Médica, Departamento de Ciencias de la Naturaleza, Centro Universitario del Sur, Universidad de Guadalajara, 49000, Ciudad Guzmán, Jalisco, México
| | - Paulo Daniel Rúa-Vázquez
- Maestría en Salud Pública, División de Ciencias de la Salud, Centro Universitario del Sur, Universidad de Guadalajara, 49000, Ciudad Guzmán, Jalisco, México
| | - José Francisco Montealegre-Bautista
- Maestría en Salud Pública, División de Ciencias de la Salud, Centro Universitario del Sur, Universidad de Guadalajara, 49000, Ciudad Guzmán, Jalisco, México
| | - José Alejandro Martínez-Ibarra
- Laboratorio de Entomología Médica, Departamento de Ciencias de la Naturaleza, Centro Universitario del Sur, Universidad de Guadalajara, 49000, Ciudad Guzmán, Jalisco, México,
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Lozada-Yavina R, Marchant C, Cancino-Faure B, Hernández-Rodríguez EW, Córdova-Lepe F. A description of the epidemiological dynamics of Chagas disease via mathematical modeling. Acta Trop 2023; 243:106930. [PMID: 37098356 DOI: 10.1016/j.actatropica.2023.106930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 04/15/2023] [Accepted: 04/19/2023] [Indexed: 04/27/2023]
Abstract
Chagas disease is caused by the protozoan Trypanosoma cruzi, which parasitizes many mammals, including humans. Its vectors are blood-feeding hematophagous triatomine insects of different species, which vary according to the geographical area. One of the 17 neglected diseases targeted by the World Health Organization, Chagas disease is endemic to the Americas, but has spread to other countries due to human migratory movements. In this study, we describe the epidemiological dynamics of Chagas disease in an endemic area, considering the main transmission mechanisms and the demographic effects of birth, mortality, and human migration in this phenomenon. We apply mathematical models as a methodological approach to simulate the interactions between reservoirs, vectors, and humans using a system of ordinary differential equations. The results show that the Chagas disease control measures currently in place cannot be relaxed without endangering the progress achieved to date.
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Affiliation(s)
- Rafael Lozada-Yavina
- Departamento de Matemática, Física y Estadística, Facultad de Ciencias Básicas, Universidad Católica del Maule, Talca, 3480112, Chile.
| | - Carolina Marchant
- Departamento de Matemática, Física y Estadística, Facultad de Ciencias Básicas, Universidad Católica del Maule, Talca, 3480112, Chile
| | - Beatriz Cancino-Faure
- Laboratorio de Microbiología y Parasitología, Departamento de Ciencias Preclínicas, Facultad de Medicina, Universidad Católica del Maule, Talca, 3480112, Chile
| | - Erix W Hernández-Rodríguez
- Laboratorio de Bioinformática y Química Computacional, Departamento de Medicina Traslacional, Facultad de Medicina, Universidad Católica del Maule, Talca, 3480112, Chile
| | - Fernando Córdova-Lepe
- Departamento de Matemática, Física y Estadística, Facultad de Ciencias Básicas, Universidad Católica del Maule, Talca, 3480112, Chile
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Gual-Gonzalez L, Medina M, Valverde-Castro C, Beltrán V, Caro R, Triana-Chávez O, Nolan MS, Cantillo-Barraza O. Laboratory Evaluation and Field Feasibility of Micro-Encapsulated Insecticide Effect on Rhodnius prolixus and Triatoma dimidiata Mortality in Rural Households in Boyacá, Colombia. INSECTS 2022; 13:insects13111061. [PMID: 36421964 PMCID: PMC9697714 DOI: 10.3390/insects13111061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 06/02/2023]
Abstract
Chagas disease is a neglected vector-borne zoonosis caused by the parasite Trypanosoma cruzi that is primarily transmitted by insects of the subfamily Triatominae. Although control efforts targeting domestic infestations of Rhodnius prolixus have been largely successful, with several regions in Boyacá department certified free of T. cruzi transmission by intradomicile R. prolixus, novel native species are emerging, increasing the risk of disease. Triatoma dimidiata is the second most important species in Colombia, and conventional control methods seem to be less effective. In this study we evaluated the efficacy and usefulness of micro-encapsulated insecticide paints in laboratory conditions and its applicability in rural communities to avoid triatomine domiciliation. Laboratory conditions measured mortality at 6 months and 12 months, with an average mortality between 93-100% for T. dimidiata and 100% for R. prolixus. Evaluation of triatomine infestation in rural households was measured after one year, with an overall perception of effectiveness in reducing household domiciliation. Although triatomines were still spotted inside and around the homes, our findings demonstrate the ability of micro-encapsulated insecticide to prevent colonization inside the households when comparing infestation rates from previous years. Current control measures suggest insecticide spraying every six months, which implies great economic cost and logistical effort. Complementary triatomine control measures with insecticide spraying and micro-encapsulated insecticide paint would make public health efforts more efficient and reduce the frequency of treatment.
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Affiliation(s)
- Lídia Gual-Gonzalez
- Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA
| | - Manuel Medina
- Unidad de Control de Enfermedades Transmitidas por Vectores, Secretaría de Salud Boyacá, Tunja 150001, Colombia
| | - César Valverde-Castro
- Grupo de Investigación en Medicina Tropical, Universidad del Magdalena, Santa Marta 470003, Colombia
- Grupo Biología y Control Enfermedades Infecciosas, Universidad Antioquia, Medellín 050010, Colombia
| | - Virgilio Beltrán
- Unidad de Control de Enfermedades Transmitidas por Vectores, Secretaría de Salud Boyacá, Tunja 150001, Colombia
| | - Rodrigo Caro
- Unidad de Control de Enfermedades Transmitidas por Vectores, Secretaría de Salud Boyacá, Tunja 150001, Colombia
| | - Omar Triana-Chávez
- Grupo Biología y Control Enfermedades Infecciosas, Universidad Antioquia, Medellín 050010, Colombia
| | - Melissa S. Nolan
- Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA
| | - Omar Cantillo-Barraza
- Grupo Biología y Control Enfermedades Infecciosas, Universidad Antioquia, Medellín 050010, Colombia
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Nieto-Sanchez C, Hatley DM, Grijalva MJ, Peeters Grietens K, Bates BR. Communication in Neglected Tropical Diseases' elimination: A scoping review and call for action. PLoS Negl Trop Dis 2022; 16:e0009774. [PMID: 36228006 PMCID: PMC9595560 DOI: 10.1371/journal.pntd.0009774] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/25/2022] [Accepted: 09/27/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Although the practice of communication is often called upon when intervening and involving communities affected by NTDs, the disciplinary framework of health communication research has been largely absent from NTD strategies. To illustrate how practices conceptualized and developed within the communication field have been applied in the context of NTD elimination, we conducted a scoping review focusing on two diseases currently targeted for elimination by the WHO: lymphatic filariasis and Chagas disease. METHODS We examined studies published between 2012 and 2020 in five electronic databases. Selected articles were required to (i) have explicit references to communication in either the abstract, title, or key words; (ii) further elaborate on the search terms (communication, message, media, participation and health education) in the body of the article; and (iii) sufficiently describe communication actions associated to those terms. Using the C-Change Socio-Ecological Model for Social and Behavior Change Communication as a reference, the articles were analysed to identify communication activities, theoretical frameworks, and/or rationales involved in their design, as well as their intended level of influence (individual, interpersonal, community, or enabling environment). RESULTS AND IMPLICATIONS A total of 43 articles were analysed. Most interventions conceptualized communication as a set of support tools or supplemental activities delivering information and amplifying pre-defined messages aimed at increasing knowledge, encouraging community involvement, promoting individual behavior change, or securing some degree of acceptability of proposed strategies. Although important attempts at further exploring communication capabilities were identified, particularly in participation-based strategies, for most studies, communication consisted of an underdeveloped and under-theorized approach. We contend that a more complex understanding of the capacities offered by the health communication field could help attain the biomedical and social justice goals proposed in NTD elimination strategies. Three ways in which the field of health communication could further enhance NTD efforts are presented: informing interventions with theory-based frameworks, exploring the political complexity of community participation in specific contexts, and identifying conceptualizations of culture implied in interventions' design. CONCLUSION This article is a call to action to consider the resources offered by the health communication field when researching, designing, or implementing NTD interventions.
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Affiliation(s)
- Claudia Nieto-Sanchez
- Socio-Ecological Health Research Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
- * E-mail:
| | - David M. Hatley
- Department of Epidemiology, University of London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Mario J. Grijalva
- Infectious and Tropical Disease Institute (ITDI), Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
- Center for Research in Health in Latin America (CISeAL), Facultad de Ciencias Exactas y Naturales, Pontifical Catholic University of Ecuador, Quito, Ecuador
| | - Koen Peeters Grietens
- Socio-Ecological Health Research Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
- Nagasaki, School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan
| | - Benjamin R. Bates
- Infectious and Tropical Disease Institute (ITDI), Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
- Center for Research in Health in Latin America (CISeAL), Facultad de Ciencias Exactas y Naturales, Pontifical Catholic University of Ecuador, Quito, Ecuador
- School of Communication Studies, Ohio University, Athens, Ohio, United States of America
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Gabrielli S, Macchioni F, Spinicci M, Strohmeyer M, Roselli M, Nicoletti A, Cicero CE, Poma V, Rojo D, Lara Y, Gómez EBC, Rojas P, Gamboa H, Villagran AL, Cosmi F, Monasterio J, Cancrini G, Bartoloni A. Long-Standing International Cooperation in Parasitology Research: A Summary of 35 Years of Activities in the Bolivian Chaco. Trop Med Infect Dis 2022; 7:tropicalmed7100275. [PMID: 36288016 PMCID: PMC9611245 DOI: 10.3390/tropicalmed7100275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/21/2022] [Accepted: 09/24/2022] [Indexed: 11/16/2022] Open
Abstract
The Bolivian Chaco is a semiarid region with a low population density, situated in the southeast part of the Plurinational State of Bolivia. Here, despite the improvements of the last 15 years, poverty remains high in rural areas, where social vulnerability is widespread. The Guaraní ethnic group often lives in isolated communities with a low standard of hygiene and sanitation. This epidemiological scenario favors the spread of transmissible diseases, including several parasitic infections belonging to the neglected tropical diseases (NTDs) group. In this area, a long-standing research activity, built upon the synergism between local and foreign institutions, has been established since the late 1980s and helps to fill in the knowledge gap about the epidemiology dynamics of soil-transmitted helminths, vector-borne parasites, and other parasitic diseases. A 35-year history of cooperation programs in parasitology research has contributed to informing local health authorities of the NTD burden in the Bolivian Chaco and, ultimately, supports local healthcare providers in the management of parasitic diseases.
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Affiliation(s)
- Simona Gabrielli
- Dipartimento di Sanità Pubblica e Malattie Infettive, Sapienza Università di Roma, 00185 Rome, Italy
| | - Fabio Macchioni
- Dipartimento di Scienze Veterinarie, Università di Pisa, 56124 Pisa, Italy
| | - Michele Spinicci
- Dipartimento Medicina Sperimentale e Clinica, Università degli Studi di Firenze, 50121 Florence, Italy
| | - Marianne Strohmeyer
- Dipartimento Medicina Sperimentale e Clinica, Università degli Studi di Firenze, 50121 Florence, Italy
| | - Mimmo Roselli
- Dipartimento Medicina Sperimentale e Clinica, Università degli Studi di Firenze, 50121 Florence, Italy
| | - Alessandra Nicoletti
- Dipartimento di Scienze Mediche, Chirurgiche e Tecnologie Avanzate G.F. Ingrassia, Sez. di Neuroscienze, Università di Catania, 95125 Catania, Italy
| | - Calogero Edoardo Cicero
- Dipartimento di Scienze Mediche, Chirurgiche e Tecnologie Avanzate G.F. Ingrassia, Sez. di Neuroscienze, Università di Catania, 95125 Catania, Italy
| | - Veronica Poma
- Escuela de Salud del Chaco Tekove Katu, Gutierrez, Bolivia
| | - David Rojo
- Escuela de Salud del Chaco Tekove Katu, Gutierrez, Bolivia
| | - Yunni Lara
- Hospital San Antonio de los Sauces, Monteagudo, Bolivia
| | | | | | - Herlan Gamboa
- Facultad Integral del Chaco, Universidad Autónoma Gabriel René Moreno, Camiri, Bolivia
| | | | | | - Joaquín Monasterio
- Servicio Departamental de Salud (SEDES) de Santa Cruz, Santa Cruz, Bolivia
| | - Gabriella Cancrini
- Dipartimento di Sanità Pubblica e Malattie Infettive, Sapienza Università di Roma, 00185 Rome, Italy
| | - Alessandro Bartoloni
- Dipartimento Medicina Sperimentale e Clinica, Università degli Studi di Firenze, 50121 Florence, Italy
- Correspondence:
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Grijalva MJ, Villacís AG, Ocaña-Mayorga S, Yumiseva CA, Nieto-Sanchez C, Baus EG, Moncayo AL. Evaluation of the Effectiveness of Chemical Control for Chagas Disease Vectors in Loja Province, Ecuador. Vector Borne Zoonotic Dis 2022; 22:449-458. [PMID: 36044033 PMCID: PMC9508444 DOI: 10.1089/vbz.2021.0089] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The objective of this study was to evaluate the effectiveness of selective and community-wide house insecticide spraying in controlling triatomines in the subtropical areas of Loja Province, Ecuador. We designed a quasi-experimental pre-post-test without a control group to compare entomological levels before and after spraying. The baseline study was conducted in 2008. Second, third, and fourth visits were conducted in 2010, 2011, and 2012 in three rural communities. Out of the 130 domestic units (DU) visited, 41 domestic units were examined in each of the four visits. Selective and community-wide insecticide interventions included spraying with 5% deltamethrin at 25 mg/m2 active ingredient. At each visit, a questionnaire was administered to identify the characteristics of households, and DUs were searched for triatomine bugs. In addition, parasitological analysis was carried out in life triatomines. One and two rounds of selective insecticide spraying decreased the probability of infestation by 62% (pairwise odds ratios [POR] 0.38, 95% confidence interval [CI] 0.17-0.89, p = 0.024) and 51% (POR 0.49, 95% CI 0.23-1.01, p = 0.054), respectively. A similar effect was observed after one round of community-wide insecticide application in Chaquizhca and Guara (POR 0.55, CI 0.24-1.25, p = 0.155) and Bellamaria (POR 0.62, CI 0.22-1.79, p = 0.379); however, it was not statistically significant. Trypanosoma cruzi infection in triatomines (n = 483) increased overtime, from 2008 (42.9% and 8.5% for Rhodnius ecuadoriensis and Panstrongylus chinai, respectively) to 2012 (79.5% and 100%). Neither of the two spraying methodologies was effective for triatomine control in this area and our results point to a high likelihood of reinfestation after insecticide application. This underscores the importance of the implementation of physical barriers that prevent invasion and colonization of triatomines in households, such as home improvement initiatives, accompanied by a concerted effort to address the underlying socioeconomic issues that keep this population at risk of developing Chagas disease.
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Affiliation(s)
- Mario J. Grijalva
- Infectious and Tropical Disease Institute, Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, USA
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Anita G. Villacís
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Sofia Ocaña-Mayorga
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - César A. Yumiseva
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Claudia Nieto-Sanchez
- Infectious and Tropical Disease Institute, Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, USA
- Unit of Socio-Ecological Health Research, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Esteban G. Baus
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
- Facultad de Medicina, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Ana L. Moncayo
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
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Chastonay AHM, Chastonay OJ. Housing Risk Factors of Four Tropical Neglected Diseases: A Brief Review of the Recent Literature. Trop Med Infect Dis 2022; 7:tropicalmed7070143. [PMID: 35878154 PMCID: PMC9319438 DOI: 10.3390/tropicalmed7070143] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/12/2022] [Accepted: 07/19/2022] [Indexed: 01/27/2023] Open
Abstract
Alongside peace, education, food, income, a stable ecosystem, sustainable resources and social justice, shelter is a prerequisite for health. According to international human rights law, everyone is entitled to an adequate standard of living, which includes adequate housing. Adequate housing, including access to water and sanitation, plays a critical role in the prevention and management of neglected tropical diseases, which affect over 1 billion people worldwide. Inadequate housing conditions represent a risk factor for many of them, e.g., Chagas disease that affects 6–8 million people worldwide, visceral leishmaniasis that kills 20,000–30,000 people/year, lymphatic filariasis which threatens 859 million people worldwide or dengue that has increased 8–10 fold over the last two decades. Vector control strategies for the above-mentioned diseases have shown their effectiveness and should include systematic and repetitive in-house spraying and individual protection (e.g., impregnated nets), as well as better-quality construction material and techniques and better sanitation infrastructures and practices. Access to adequate housing is a basic human right. The violation of the right to adequate housing may affect the enjoyment of other human rights. Access to adequate housing can strengthen (and facilitate access to) other basic human rights, such as the rights to work, health, security, and education.
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Affiliation(s)
| | - Oriane J. Chastonay
- Réseau Fribourgeois de Santé Mentale, 1700 Fribourg, Switzerland
- Correspondence:
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8
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Gonçalves R, Landivar D, Grover Sañez Liendo E, Mamani Fernandez J, Ismail HM, Paine MJI, Courtenay O, Bern C. Improving houses in the Bolivian Chaco increases effectiveness of residual insecticide spraying against infestation with Triatoma infestans, vector of Chagas disease. Trop Med Int Health 2021; 26:1127-1138. [PMID: 34114721 DOI: 10.1111/tmi.13640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Failure to control domestic Triatoma infestans in the Chaco is attributed to vulnerable adobe construction, which provides vector refuges and diminishes insecticide contact. We conducted a pilot to test the impact of housing improvement plus indoor residual spraying (IRS) on house infestation and vector abundance in a rural community in the Bolivian Chaco. METHODS The intervention included three arms: housing improvement + IRS [HI], assisted IRS [AS] in which the team helped to clear the house pre-IRS and routine IRS [RS]. HI used locally available materials, traditional construction techniques and community participation. Vector parameters were assessed by Timed Manual Capture for 2 person-hours per house at baseline and medians of 114, 173, 314, 389 and 445 days post-IRS-1. A second IRS round was applied at a median of 314 days post-IRS-1. RESULTS Post-intervention infestation indices and abundance fell in all three arms. The mean odds of infestation was 0.29 (95% CL 0.124, 0.684) in the HI relative to the RS arm. No difference was observed between AS and RS. Vector abundance was reduced by a mean 44% (24.8, 58.0) in HI compared to RS, with no difference between AS and RS. Median delivered insecticide concentrations per house were lower than the target of 50 mg/m2 in >90% of houses in all arms. CONCLUSION Housing improvement using local materials and community participation is a promising strategy to improve IRS effectiveness in the Bolivian Chaco. A larger trial is needed to quantify the impact on reinfestation over time.
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Affiliation(s)
- Raquel Gonçalves
- Zeeman Institute and School of Life Sciences, University of Warwick, Coventry, UK
| | | | | | | | - Hanafy M Ismail
- Liverpool School of Tropical Medicine, Department of Vector Biology, Liverpool, UK
| | - Mark J I Paine
- Liverpool School of Tropical Medicine, Department of Vector Biology, Liverpool, UK
| | - Orin Courtenay
- Zeeman Institute and School of Life Sciences, University of Warwick, Coventry, UK
| | - Caryn Bern
- Department of Epidemiology and Biostatistics, School of Medicine, University of California San Francisco, San Francisco, CA, USA
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9
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Gonçalves R, Logan RAE, Ismail HM, Paine MJI, Bern C, Courtenay O. Indoor residual spraying practices against Triatoma infestans in the Bolivian Chaco: contributing factors to suboptimal insecticide delivery to treated households. Parasit Vectors 2021; 14:327. [PMID: 34134775 PMCID: PMC8207695 DOI: 10.1186/s13071-021-04831-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 06/09/2021] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Indoor residual spraying (IRS) of insecticides is a key method to reduce vector transmission of Trypanosoma cruzi, causing Chagas disease in a large part of South America. However, the successes of IRS in the Gran Chaco region straddling Bolivia, Argentina, and Paraguay, have not equalled those in other Southern Cone countries. AIMS This study evaluated routine IRS practices and insecticide quality control in a typical endemic community in the Bolivian Chaco. METHODS Alpha-cypermethrin active ingredient (a.i.) captured onto filter papers fitted to sprayed wall surfaces, and in prepared spray tank solutions, were measured using an adapted Insecticide Quantification Kit (IQK™) validated against HPLC quantification methods. The data were analysed by mixed-effects negative binomial regression models to examine the delivered insecticide a.i. concentrations on filter papers in relation to the sprayed wall heights, spray coverage rates (surface area / spray time [m2/min]), and observed/expected spray rate ratios. Variations between health workers and householders' compliance to empty houses for IRS delivery were also evaluated. Sedimentation rates of alpha-cypermethrin a.i. post-mixing of prepared spray tanks were quantified in the laboratory. RESULTS Substantial variations were observed in the alpha-cypermethrin a.i. concentrations delivered; only 10.4% (50/480) of filter papers and 8.8% (5/57) of houses received the target concentration of 50 mg ± 20% a.i./m2. The delivered concentrations were not related to those in the matched spray tank solutions. The sedimentation of alpha-cypermethrin a.i. in the surface solution of prepared spray tanks was rapid post-mixing, resulting in a linear 3.3% loss of a.i. content per minute and 49% loss after 15 min. Only 7.5% (6/80) of houses were sprayed at the WHO recommended rate of 19 m2/min (± 10%), whereas 77.5% (62/80) were sprayed at a lower than expected rate. The median a.i. concentration delivered to houses was not significantly associated with the observed spray coverage rate. Householder compliance did not significantly influence either the spray coverage rates or the median alpha-cypermethrin a.i. concentrations delivered to houses. CONCLUSIONS Suboptimal delivery of IRS is partially attributable to the insecticide physical characteristics and the need for revision of insecticide delivery methods, which includes training of IRS teams and community education to encourage compliance. The IQK™ is a necessary field-friendly tool to improve IRS quality and to facilitate health worker training and decision-making by Chagas disease vector control managers.
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Affiliation(s)
- Raquel Gonçalves
- Zeeman Institute and School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Rhiannon A E Logan
- Liverpool School of Tropical Medicine, Department of Vector Biology, Faculty of Biological Sciences, Pembroke Place, Liverpool, L3 5QA, UK
| | - Hanafy M Ismail
- Liverpool School of Tropical Medicine, Department of Vector Biology, Faculty of Biological Sciences, Pembroke Place, Liverpool, L3 5QA, UK
| | - Mark J I Paine
- Liverpool School of Tropical Medicine, Department of Vector Biology, Faculty of Biological Sciences, Pembroke Place, Liverpool, L3 5QA, UK
| | - Caryn Bern
- Department of Epidemiology and Biostatistics, School of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Orin Courtenay
- Zeeman Institute and School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK.
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10
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Abrahan L, Cavallo MJ, Amelotti I. Impact of involving the community in entomological surveillance of Triatoma infestans (Klug, 1834) (Hemiptera, Triatominae) vectorial control. Parasit Vectors 2021; 14:98. [PMID: 33546756 PMCID: PMC7866874 DOI: 10.1186/s13071-021-04608-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/23/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Vectorial transmission is the principal path of infection by Trypanosoma cruzi, the parasite that causes Chagas disease. In Argentina, Triatoma infestans is the principal vector; therefore, vector control is the main strategy for the prevention of this illness. The Provincial Program of Chagas La Rioja (PPCHLR) carries out entomological evaluation of domiciliary units (DUs) and spraying of those where T. infestans is found. The lack of government funds has led to low visitation frequency by the PPCHLR, especially in areas with a low infestation rate, which are not prioritized. Therefore, seeking possible alternatives to complement control activities is necessary. Involving householders in entomological evaluation could be a control alternative. The major objective was to determine the cost of entomological evaluation with and without community participation. METHODS For entomological evaluation without community participation, PPCHLR data collected in February 2017 over 359 DUs of the Castro Barros Department (CBD) were used. For entomological evaluation with community participation, 434 DUs of the same department were selected in November 2017. Each householder was trained in collecting insects, which were kept in labeled plastic bags, recovered after 2 weeks, and analyzed in the laboratory for the presence of T. cruzi. Using householders' collection data, a spatial scan statistic was used to detect clusters of different T. infestans infestations. Entomological evaluation costs with and without community participation related to the numbers of DUs visited, DUs evaluated, and DUs sprayed were calculated and compared between methodologies. In addition, the number of DUs evaluated of the DUs visited was compared. RESULTS According to the results, the triatomines did not show evidence of T. cruzi infection. Spatial analysis detected heterogeneity of T. infestans infestation in the area. Costs related to the DUs visited, evaluated, and sprayed were lower with community participation (p < 0.05). In addition, more DUs were evaluated in relation to those visited and a greater surface area was covered with community participation. CONCLUSION Participation of the community in the infestation survey is an efficient complement to vertical control, allowing the spraying to be focused on infested houses and thus reducing the PPCHLR's costs and intervention times.
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Affiliation(s)
- L Abrahan
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), UNLAR, SEGEMAR, UNCa, CONICET, Entre Ríos y Mendoza s/n, Anillaco (5301), La Rioja, Provincia de La Rioja, Argentina.
| | - M J Cavallo
- Centro de Investigaciones y Transferencias de Catamarca (CITCA)-CONICET-UNCA, San Fernando del Valle de Catamarca, Catamarca, Argentina
| | - I Amelotti
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), UNLAR, SEGEMAR, UNCa, CONICET, Entre Ríos y Mendoza s/n, Anillaco (5301), La Rioja, Provincia de La Rioja, Argentina
- Universidad Nacional de La Rioja (UNLAR), La Rioja, Argentina
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11
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Alvedro A, Gaspe MS, Milbourn H, Macchiaverna NP, Laiño MA, Enriquez GF, Gürtler RE, Cardinal MV. Trypanosoma cruzi infection in Triatoma infestans and high levels of human-vector contact across a rural-to-urban gradient in the Argentine Chaco. Parasit Vectors 2021; 14:35. [PMID: 33422133 PMCID: PMC7796388 DOI: 10.1186/s13071-020-04534-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 12/10/2020] [Indexed: 11/24/2022] Open
Abstract
Background Peri-urban and urban settings have recently gained more prominence in studies on vector-borne transmission of Trypanosoma cruzi due to sustained rural-to-urban migrations and reports of urban infestations with triatomines. Prompted by the finding of Triatoma infestans across the rural-to-urban gradient in Avia Terai, an endemic municipality of the Argentine Chaco, we assessed selected components of domestic transmission risk in order to determine its variation across the gradient. Methods A baseline vector survey was conducted between October 2015 and March 2016, following which we used multistage random sampling to select a representative sample of T. infestans at the municipal level. We assessed T. cruzi infection and blood-feeding sources of 561 insects collected from 109 houses using kinetoplast DNA-PCR assays and direct enzyme-linked immunosorbent assays, respectively. We stratified triatomines according to their collection site (domestic or peridomestic), and we further categorized peridomestic sites in ecotopes of low- or high-risk for T. cruzi infection. Results The overall adjusted prevalence of T. cruzi-infected T. infestans was 1.8% (95% confidence interval [CI] 1.3–2.3) and did not differ between peri-urban (1.7%) and rural (2.2%) environments. No infection was detected in bugs captured in the urban setting; rather, infected triatomines were mainly collected in rural and peri-urban domiciles, occurring in 8% of T. infestans-infested houses. The main blood-feeding sources of domestic and peridomestic triatomines across the gradient were humans and chickens, respectively. The proportion of triatomines that had fed on humans did not differ between peri-urban (62.5%) and rural (65.7%) domiciles, peaking in the few domestic triatomines collected in urban houses and decreasing significantly with an increasing proportion of chicken- and dog- or cat-fed bugs. The relative odds ratio (OR) of having a T. cruzi infection was nearly threefold higher in bugs having a blood meal on humans (OR 3.15), dogs (OR 2.80) or cats (OR: 4.02) in a Firth-penalized multiple logistic model. Conclusions Trypanosoma cruzi transmission was likely occurring both in peri-urban and rural houses of Avia Terai. Widespread infestation in a third of urban blocks combined with high levels of human–triatomine contact in the few infested domiciles implies a threat to urban inhabitants. Vector control strategies and surveillance originally conceived for rural areas should be tailored to peri-urban and urban settings in order to achieve sustainable interruption of domestic transmission in the Chaco region.![]()
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Affiliation(s)
- Alejandra Alvedro
- Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María Sol Gaspe
- Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Natalia Paula Macchiaverna
- Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mariano Alberto Laiño
- Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gustavo Fabián Enriquez
- Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ricardo Esteban Gürtler
- Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Marta Victoria Cardinal
- Laboratorio de Eco-Epidemiología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina. .,Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires, Buenos Aires, Argentina.
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12
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Silva RAD, Wanderley DMV, Forsyth C, Leite RM, Luna EJDA, Carneiro Júnior N, Shikanai-Yasuda MA. Awareness of Chagas disease and socioeconomic characteristics of Bolivian immigrants living in Sao Paulo, Brazil. Rev Inst Med Trop Sao Paulo 2020; 62:e39. [PMID: 32578725 PMCID: PMC7304264 DOI: 10.1590/s1678-9946202062039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 05/18/2020] [Indexed: 11/29/2022] Open
Abstract
In this study which is part of a research project on Chagas disease (CD) among Bolivian immigrants in Sao Paulo, we describe socioeconomic characteristics, knowledge of CD and implications for acess to health care. We applied a structured questionnaire to a sample of 472 Bolivian adults (> 18 years) living in Sao Paulo and enrolled at the Barra Funda School Health Center. Participants’ median age was 28.5 years, 75.0% were from the Bolivian department of La Paz, and >90% worked in the garment industry. Respondents had lived in Sao Paulo for a median of 5.8 years. Only 169 (35.8%) were familiar with CD, while roughly half (50.4%) had lived in natural materials houses in Bolivia, 225 (47.7%) indicated familiarity with the vector, 23.9% had seen the vector in their homes in Bolivia, and 6.4% reported having been bitten by a triatomine bug. Factors associated with awareness of CD were analyzed by chi square tests, and those with p values <0.25 were included in a multivariable logistic regression model. In the multivariable logistic regression analysis, having a relative with CD (OR=4.3, 95% CI=1.5-12.0), having lived in a house with mud or wood walls (OR=0.4, 95% CI=0.2-0.8), and having heard of the triatomine bug, or vinchuca, (OR=10.0, 95% CI=5.1-19.5) were significantly associated with awareness of CD. This study shows a low familiarity with CD among Bolivian migrants living in Sao Paulo, Brazil. Raising awareness of the disease through specific communication strategies should be an essential component of public health programs to reduce the burden of CD in this and other vulnerable populations.
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Affiliation(s)
- Rubens Antonio da Silva
- Secretaria de Estado da Saúde de São Paulo, Superintendência de Controle de Endemias, São Paulo, Brazil
| | | | - Colin Forsyth
- Drugs for Neglected Diseases iniciative (DNDi), Geneva, Switzerland
| | - Ruth Moreira Leite
- Secretaria de Estado da Saúde de São Paulo, Centro de Vigilância Epidemiológica, São Paulo, São Paulo, Brazil
| | | | | | - Maria Aparecida Shikanai-Yasuda
- Universidade de São Paulo, Instituto de Medicina Tropical de São Paulo, São Paulo, São Paulo, Brazil.,Universidade de São Paulo, Faculdade de Medicina, Departamento de Moléstias Infecciosas e Parasitárias, Laboratório de Investigação Médica em Imunologia (LIM-48), São Paulo, São Paulo, Brazil
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13
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Flores-Ferrer A, Waleckx E, Rascalou G, Dumonteil E, Gourbière S. Trypanosoma cruzi transmission dynamics in a synanthropic and domesticated host community. PLoS Negl Trop Dis 2019; 13:e0007902. [PMID: 31834879 PMCID: PMC6934322 DOI: 10.1371/journal.pntd.0007902] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 12/27/2019] [Accepted: 11/04/2019] [Indexed: 12/26/2022] Open
Abstract
Trypanosoma cruzi is the causative agent of Chagas disease, a Neglected Tropical Disease affecting 8 million people in the Americas. Triatomine hematophagous vectors feed on a high diversity of vertebrate species that can be reservoirs or dead-end hosts, such as avian species refractory to T. cruzi. To understand its transmission dynamics in synanthropic and domesticated species living within villages is essential to quantify disease risk and assess the potential of zooprophylaxis. We developed a SI model of T. cruzi transmission in a multi-host community where vector reproduction and parasite transmission depend on a triatomine blood-feeding rate accounting for vector host preferences and interference while feeding. The model was parameterized to describe T. cruzi transmission in villages of the Yucatan peninsula, Mexico, using the information about Triatoma dimidiata vectors and host populations accumulated over the past 15 years. Extensive analyses of the model showed that dogs are key reservoirs and contributors to human infection, as compared to synanthropic rodents and cats, while chickens or other domesticated avian hosts dilute T. cruzi transmission despite increasing vector abundance. In this context, reducing the number of dogs or increasing avian hosts abundance decreases incidence in humans by up to 56% and 39%, respectively, while combining such changes reduces incidence by 71%. Although such effects are only reached over >10-years periods, they represent important considerations to be included in the design of cost-effective Integrated Vector Management. The concomitant reduction in T. cruzi vector prevalence estimated by simulating these zooprophylactic interventions could indeed complement the removal of colonies from the peridomiciles or the use of insect screens that lower vector indoor abundance by ~60% and ~80%. These new findings reinforce the idea that education and community empowerment to reduce basic risk factors is a cornerstone to reach and sustain the key objective of interrupting Chagas disease intra-domiciliary transmission.
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Affiliation(s)
- Alheli Flores-Ferrer
- UMR5096 ‘Laboratoire Génome et Développement des Plantes’, Université de Perpignan Via Domitia, Perpignan, France
| | - Etienne Waleckx
- Institut de Recherche pour le Développement, UMR INTERTRYP IRD, CIRAD, Université de Montpellier, Montpellier, France
- Laboratorio de Parasitología, Centro de Investigaciones Regionales ‘Dr. Hideyo Noguchi’, Universidad Autónoma deYucatán, Mérida, Yucatán, México
| | - Guilhem Rascalou
- UMR5096 ‘Laboratoire Génome et Développement des Plantes’, Université de Perpignan Via Domitia, Perpignan, France
| | - Eric Dumonteil
- Department of Tropical Medicine, School of Public Health and Tropical Medicine, and Vector-Borne and Infectious Disease Research Center, Tulane University, New Orleans, Louisiana, United States of America
| | - Sébastien Gourbière
- UMR5096 ‘Laboratoire Génome et Développement des Plantes’, Université de Perpignan Via Domitia, Perpignan, France
- Centre for the Study of Evolution, School of Life Sciences, University of Sussex, Brighton, United Kingdom
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14
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Calderon-Anyosa R, Galvez-Petzoldt C, Garcia PJ, Carcamo CP. Housing Characteristics and Leishmaniasis: A Systematic Review. Am J Trop Med Hyg 2019; 99:1547-1554. [PMID: 30382013 DOI: 10.4269/ajtmh.18-0037] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Leishmaniasis is a major neglected tropical disease associated with high rates of disability and death. This disease is associated with poverty, which can be reflected in housing quality, especially in rural areas. This systematic review found that mud walls with cracks and holes, damp, and dark houses were risk factors for transmission of leishmaniasis. These characteristics create favorable conditions for sand fly breeding and resting as sand flies prefer humidity, warmth, and protection from sunlight during the day. Housing interventions might be a promising research area with a special focus on education as individual and collective protection for the effective control of leishmaniasis.
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Affiliation(s)
- Renzo Calderon-Anyosa
- Kuskaya Program, School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Camila Galvez-Petzoldt
- Kuskaya Program, School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Patricia J Garcia
- Kuskaya Program, School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Cesar P Carcamo
- Kuskaya Program, School of Public Health and Administration, Universidad Peruana Cayetano Heredia, Lima, Peru
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15
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Salm A, Gertsch J. Cultural perception of triatomine bugs and Chagas disease in Bolivia: a cross-sectional field study. Parasit Vectors 2019; 12:291. [PMID: 31182163 PMCID: PMC6558697 DOI: 10.1186/s13071-019-3546-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 05/30/2019] [Indexed: 01/09/2023] Open
Abstract
Background Chagas disease remains a major public health risk in Bolivia, particularly among rural indigenous communities. Here we studied the cultural perception of the triatomine vectors and Chagas disease among selected rural and urban ethnic groups from different socio-economic and geographical milieus. We focused on the indigenous communities in the Bolivian Chaco where the disease is hyperendemic. Methods A cross-sectional study using field observations and structured interviews was carried out among 480 informants in five different regions of Bolivia. Additional semi-structured interviews were conducted. Statistical analyses were performed to determine the correlation of socio-economic variables and indigenous Chagas disease knowledge systems. A total of 170 domestic Triatoma infestans vectors were collected and infection with Trypanosoma cruzi was analyzed by real-time PCR. Results Triatomine bugs were associated with Chagas disease in 70.2% (n = 480) of the responses (48.0% Ayoreo, 87.5% Chiquitano, 83.9% Guaraní, 72.2% Quechua, 46.1% La Paz citizens and 67.7% Santa Cruz citizens). Generally, indigenous informants have been educated on the association between triatomine bugs and Chagas disease by institutional anti-Chagas disease campaigns. While communities were largely aware of the vectors as a principal mode of disease transmission, rather unexpectedly, health campaigns had little influence on their prevention practices, apparently due to cultural constraints. Overall, 71.9% of the collected domestic vectors in the Chaco region were infected with T. cruzi, matching the high infection rates in the indigenous communities. Conclusions Among the Guaraní, Ayoreo and Quechua communities, the groups living in traditional houses have not integrated the scientific knowledge about Chagas disease transmission into their daily hygiene and continue to cohabit with T. infestans vectors hyperinfected with T. cruzi. An effective translation of Western disease concepts into traditional preventive measures is missing because asymptomatic infections are not generally perceived as threat by the communities. New participatory approaches involving existing ethnomedical knowledge systems could be a successful strategy in the control of T. cruzi infection.
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Affiliation(s)
- Andrea Salm
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Jürg Gertsch
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland.
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16
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Nieto-Sanchez C, Bates BR, Guerrero D, Jimenez S, Baus EG, Peeters Grietens K, Grijalva MJ. Home improvement and system-based health promotion for sustainable prevention of Chagas disease: A qualitative study. PLoS Negl Trop Dis 2019; 13:e0007472. [PMID: 31194754 PMCID: PMC6592574 DOI: 10.1371/journal.pntd.0007472] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 06/25/2019] [Accepted: 05/16/2019] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Human transmission of Chagas disease (CD) most commonly occurs in domiciliary spaces where triatomines remain hidden to feed on blood sources during inhabitants' sleep. Similar to other neglected tropical diseases (NTDs), sustainable control of CD requires attention to the structural conditions of life of populations at risk, in this case, the conditions of their living environments. Considering socio-cultural and political dynamics involved in dwellings' construction, this study aimed to explore social factors that contribute or limit sustainability of CD's prevention models focused on home improvement. METHODS AND MAIN FINDINGS Using Healthy Homes for Healthy Living (HHHL)-a health promotion strategy focused on improvement of living environments and system-based health promotion-as a reference, a qualitative study was conducted. Research participants were selected from three rural communities of a CD endemic region in southern Ecuador involved in HHHL's refurbishment and reconstruction interventions between 2013 and 2016. Folowing an ethnographic approach, data were collected through interviews, participant observation, informal conversations and document analysis. Our results indicate that the HHHL model addressed risk factors for CD at the household level, while simultaneously promoting wellbeing at emotional, economic and social levels in local communities. We argue that sustainability of the CD prevention model proposed by HHHL is enhanced by the confluence of three factors: systemic improvement of families' quality of life, perceived usefulness of control measures, and flexibility to adapt to emerging dynamics of the context. CONCLUSION HHHL's proposed home improvement, facilitated through system-based rather than disease specific health promotion processes, enhances agency in populations at risk and facilitates community partnerships forged around CD prevention. Although an independent analysis of cost-effectiveness is recommended, structural poverty experienced by local families is still the most important factor to consider when evaluating the sustainability and scalability of this model.
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Affiliation(s)
- Claudia Nieto-Sanchez
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
- Infectious and Tropical Disease Institute, Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Benjamin R. Bates
- Infectious and Tropical Disease Institute, Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
- School of Communication Studies, Ohio University, Athens, Ohio, United States of America
| | - Darwin Guerrero
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Sylvia Jimenez
- Facultad de Arquitectura, Arte y Diseño, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Esteban G. Baus
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
| | - Koen Peeters Grietens
- Medical Anthropology Unit, Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Mario J. Grijalva
- Centro de Investigación para la Salud en América Latina, Escuela de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
- Infectious and Tropical Disease Institute, Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
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Gutfraind A, Peterson JK, Billig Rose E, Arevalo-Nieto C, Sheen J, Condori-Luna GF, Tankasala N, Castillo-Neyra R, Condori-Pino C, Anand P, Naquira-Velarde C, Levy MZ. Integrating evidence, models and maps to enhance Chagas disease vector surveillance. PLoS Negl Trop Dis 2018; 12:e0006883. [PMID: 30496172 PMCID: PMC6289469 DOI: 10.1371/journal.pntd.0006883] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 12/11/2018] [Accepted: 09/29/2018] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Until recently, the Chagas disease vector, Triatoma infestans, was widespread in Arequipa, Perú, but as a result of a decades-long campaign in which over 70,000 houses were treated with insecticides, infestation prevalence is now greatly reduced. To monitor for T. infestans resurgence, the city is currently in a surveillance phase in which a sample of houses is selected for inspection each year. Despite extensive data from the control campaign that could be used to inform surveillance, the selection of houses to inspect is often carried out haphazardly or by convenience. Therefore, we asked, how can we enhance efforts toward preventing T. infestans resurgence by creating the opportunity for vector surveillance to be informed by data? METHODOLOGY/PRINCIPAL FINDINGS To this end, we developed a mobile app that provides vector infestation risk maps generated with data from the control campaign run in a predictive model. The app is intended to enhance vector surveillance activities by giving inspectors the opportunity to incorporate the infestation risk information into their surveillance activities, but it does not dictate which houses to surveil. Therefore, a critical question becomes, will inspectors use the risk information? To answer this question, we ran a pilot study in which we compared surveillance using the app to the current practice (paper maps). We hypothesized that inspectors would use the risk information provided by the app, as measured by the frequency of higher risk houses visited, and qualitative analyses of inspector movement patterns in the field. We also compared the efficiency of both mediums to identify factors that might discourage risk information use. Over the course of ten days (five with each medium), 1,081 houses were visited using the paper maps, of which 366 (34%) were inspected, while 1,038 houses were visited using the app, with 401 (39%) inspected. Five out of eight inspectors (62.5%) visited more higher risk houses when using the app (Fisher's exact test, p < 0.001). Among all inspectors, there was an upward shift in proportional visits to higher risk houses when using the app (Mantel-Haenszel test, common odds ratio (OR) = 2.42, 95% CI 2.00-2.92), and in a second analysis using generalized linear mixed models, app use increased the odds of visiting a higher risk house 2.73-fold (95% CI 2.24-3.32), suggesting that the risk information provided by the app was used by most inspectors. Qualitative analyses of inspector movement revealed indications of risk information use in seven out of eight (87.5%) inspectors. There was no difference between the app and paper maps in the number of houses visited (paired t-test, p = 0.67) or inspected (p = 0.17), suggesting that app use did not reduce surveillance efficiency. CONCLUSIONS/SIGNIFICANCE Without staying vigilant to remaining and re-emerging vector foci following a vector control campaign, disease transmission eventually returns and progress achieved is reversed. Our results suggest that, when provided the opportunity, most inspectors will use risk information to direct their surveillance activities, at least over the short term. The study is an initial, but key, step toward evidence-based vector surveillance.
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Affiliation(s)
- Alexander Gutfraind
- Laboratory for Mathematical Analysis of Data, Complexity and Conflicts, Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL, United States of America
- Division of Hepatology, Department of Medicine, Loyola University Medical Center, Maywood, IL, United States of America
| | - Jennifer K. Peterson
- Department of Biostatistics, Epidemiology & Informatics; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Erica Billig Rose
- Department of Biostatistics, Epidemiology & Informatics; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Claudia Arevalo-Nieto
- Zoonotic Disease Research Laboratory, One Health Unit, Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Justin Sheen
- Department of Biostatistics, Epidemiology & Informatics; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
- Zoonotic Disease Research Laboratory, One Health Unit, Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Gian Franco Condori-Luna
- Zoonotic Disease Research Laboratory, One Health Unit, Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Narender Tankasala
- Laboratory for Mathematical Analysis of Data, Complexity and Conflicts, Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Ricardo Castillo-Neyra
- Department of Biostatistics, Epidemiology & Informatics; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Carlos Condori-Pino
- Zoonotic Disease Research Laboratory, One Health Unit, Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Priyanka Anand
- Department of Biostatistics, Epidemiology & Informatics; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Cesar Naquira-Velarde
- Zoonotic Disease Research Laboratory, One Health Unit, Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia, Lima, Perú
| | - Michael Z. Levy
- Department of Biostatistics, Epidemiology & Informatics; Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
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Gaspe MS, Provecho YM, Fernández MP, Vassena CV, Santo Orihuela PL, Gürtler RE. Beating the odds: Sustained Chagas disease vector control in remote indigenous communities of the Argentine Chaco over a seven-year period. PLoS Negl Trop Dis 2018; 12:e0006804. [PMID: 30278044 PMCID: PMC6168123 DOI: 10.1371/journal.pntd.0006804] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 08/29/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Rapid reinfestation of insecticide-treated dwellings hamper the sustained elimination of Triatoma infestans, the main vector of Chagas disease in the Gran Chaco region. We conducted a seven-year longitudinal study including community-wide spraying with pyrethroid insecticides combined with periodic vector surveillance to investigate the house reinfestation process in connection with baseline pyrethroid resistance, housing quality and household mobility in a rural section of Pampa del Indio mainly inhabited by deprived indigenous people (Qom). METHODOLOGY/PRINCIPAL FINDINGS Despite evidence of moderate pyrethroid resistance in local T. infestans populations, house infestation dropped from 31.9% at baseline to 0.7% at 10 months post-spraying (MPS), with no triatomine found at 59 and 78 MPS. Household-based surveillance corroborated the rare occurrence of T. infestans and the house invasion of other four triatomine species. The annual rates of loss of initially occupied houses and of household mobility were high (4.6-8.0%). Housing improvements did not translate into a significant reduction of mud-walled houses and refuges for triatomines because most households kept the former dwelling or built new ones with mud walls. CONCLUSIONS/SIGNIFICANCE Our results refute the assumption that vector control actions performed in marginalized communities of the Gran Chaco are doomed to fail. The larger-than-expected impacts of the intervention program were likely associated with the combined effects of high-coverage, professional insecticide spraying followed by systematic vector surveillance-and-response, broad geographic coverage creating a buffer zone, frequent housing replacement and residential mobility. The dynamical interactions among housing quality, mobility and insecticide-based control largely affect the chances of vector elimination.
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Affiliation(s)
- M. Sol Gaspe
- Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales, Laboratorio de Eco-Epidemiología, Ciudad Universitaria, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires. Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Ciudad Universitaria, Buenos Aires, Argentina
| | - Yael M. Provecho
- Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales, Laboratorio de Eco-Epidemiología, Ciudad Universitaria, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires. Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Ciudad Universitaria, Buenos Aires, Argentina
- Coordinación de Vectores, Dirección Nacional de Epidemiología y Análisis de la Situación de Salud, Ministerio de Salud de la Nación, Buenos Aires, Argentina
| | - María P. Fernández
- Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales, Laboratorio de Eco-Epidemiología, Ciudad Universitaria, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires. Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Ciudad Universitaria, Buenos Aires, Argentina
- Earth Institute, Columbia University, New York, New York, United States of America
| | - Claudia V. Vassena
- Centro de Investigaciones de Plagas e Insecticidas (UNIDEF, CITEDEF, CONICET, CIPEIN), Buenos Aires, Argentina
- Cátedra de Química Analítica Instrumental, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Pablo L. Santo Orihuela
- Centro de Investigaciones de Plagas e Insecticidas (UNIDEF, CITEDEF, CONICET, CIPEIN), Buenos Aires, Argentina
- Departamento de Investigación e Ingeniería Ambiental (3iA), Universidad Nacional de San Martín, Buenos Aires, Argentina
| | - Ricardo E. Gürtler
- Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales, Laboratorio de Eco-Epidemiología, Ciudad Universitaria, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad de Buenos Aires. Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), Ciudad Universitaria, Buenos Aires, Argentina
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Cavallo MJ, Amelotti I, Abrahan L, Cueto G, Gorla DE. Rural houses infestation by Triatoma infestans in northwestern Argentina: Vector control in a high spatial heterogeneous infestation area. PLoS One 2018; 13:e0201391. [PMID: 30071071 PMCID: PMC6072006 DOI: 10.1371/journal.pone.0201391] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 07/13/2018] [Indexed: 11/18/2022] Open
Abstract
Triatoma infestans (Hemiptera: Reduviidae) is a vector of the Trypanosoma cruzi parasite, causative agent of Chagas disease. During the last decade, vector control activities have been systematically carried out in northwestern Argentina, an endemic region for this disease. The general aim of this study to evaluate was spatio-temporal variation of infestation by T. infestans in rural communities of Los Llanos in La Rioja province. We estimated house infestation using two sampling methods: passive and active. Passive collection was conducted with community participation collecting triatomines. Six passive collections were carried out in 397 houses during the warm season between 2014 and 2017. Active collection of T. infestans was thoroughly performed by trained staff for 60 minutes and was carried out once in March 2016. The estimate of intradomestic infestation did not show significant differences between both collection methods (p = 0.39). However, passive collection method had lower sensitivity than active collection method for the estimation of peridomestic infestation and intradomestic colonization (PDI: p< 0.01; ID colonization: p< 0.01). The results obtained with passive collection methods showed that the infestation in the study area was spatially heterogeneous and temporally variable. Intradomiciliary infestation decreased over time (14.4% to 7.9%, p<0.05) although the effect of the chemical treatment application was not associated with the infestation level of T. infestans (p = 0.15) and the Departments had a different response each year (p<0.01). A high infestation cluster was located in the south of our study area during 2016–2017. The vector presence in the houses confirms the importance of to improve entomological surveillance programs. The search for triatomines carried out by the inhabitants might be a useful method to complement the activities of vector control programs in isolated and rural areas.
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Affiliation(s)
- María José Cavallo
- Entomología Médica, Centro Regional de Investigaciones Científicas y Transferencia La Rioja, UNLAR, SEGEMAR, UNCa, CONICET, Anillaco, La Rioja, Argentina
- * E-mail:
| | - Ivana Amelotti
- Entomología Médica, Centro Regional de Investigaciones Científicas y Transferencia La Rioja, UNLAR, SEGEMAR, UNCa, CONICET, Anillaco, La Rioja, Argentina
- Universidad Nacional de La Rioja, La Rioja, Argentina
| | - Luciana Abrahan
- Entomología Médica, Centro Regional de Investigaciones Científicas y Transferencia La Rioja, UNLAR, SEGEMAR, UNCa, CONICET, Anillaco, La Rioja, Argentina
| | - Gerardo Cueto
- Instituto de Ecología, Genética y Evolución, Buenos Aires, Argentina
| | - David E. Gorla
- Instituto de Altos Estudios Espaciales Mario Gulich, CONAE-Universidad Nacional de Córdoba, Córdoba, Argentina
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20
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Brenière SF, Buitrago R, Waleckx E, Depickère S, Sosa V, Barnabé C, Gorla D. Wild populations of Triatoma infestans: Compilation of positive sites and comparison of their ecological niche with domestic population niche. Acta Trop 2017; 176:228-235. [PMID: 28818626 DOI: 10.1016/j.actatropica.2017.08.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/26/2017] [Accepted: 08/10/2017] [Indexed: 11/15/2022]
Abstract
BACKGROUND For several years, the wild populations of Triatoma infestans, main vector of Trypanosoma cruzi causing Chagas disease, have been considered or suspected of being a source of reinfestation of villages. The number of sites reported for the presence of wild T. infestans, often close to human habitats, has greatly increased, but these data are scattered in several publications, and others obtained by our team in Bolivia have not been published yet. METHODOLOGY/PRINCIPAL FINDINGS Herein is compiled the largest number of wild sites explored for the presence of T. infestans collected with two methods The standardized methods aimed to determine the relationship between wild T. infestans and the ecoregion, and the directed method help to confirm the presence/absence of triatomines in the ecoregions. Entomological indices were compared between ecoregions and an environmental niche modelling approach, based on bioclimatic variables, was applied. The active search for wild T. infestans in Bolivia suggests a discontinuous distribution from the Andean valleys to the lowlands (Chaco), while the models used suggest a continuous distribution between the two regions and very large areas where wild populations remain to be discovered. The results compile the description of different habitats where these populations were found, and we demonstrate that the environmental niches of wild and domestic populations, defined by climatic variables, are similar but not equivalent, showing that during domestication, T. infestans has conquered new spaces with wider ranges of temperature and precipitation. CONCLUSIONS/SIGNIFICANCE The great diversity of wild T. infestans habitats and the comparison of their ecological niches with that of domestic populations confirm the behavioural plasticity of the species that increase the possibility of contact with humans. The result of the geographical distribution model of the wild populations calls for more entomological vigilance in the corresponding areas in the Southern Cone countries and in Bolivia. The current presentation is the most comprehensive inventory of wild T. infestans-positive sites that can be used as a reference for further entomological vigilance in inhabited areas.
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Affiliation(s)
- Simone Frédérique Brenière
- INTERTRYP, CIRAD, IRD, TA A-17/G, International Campus in Baillarguet, Montpellier, France; Centro de Investigación para la Salud en América Latina (CISeAL), Pontificia Universidad Católica del Ecuador (PUCE), Av. 12 de Octubre 1076 y Roca, Campus Nayón, Quito, Ecuador.
| | - Rosio Buitrago
- INTERTRYP, CIRAD, IRD, TA A-17/G, International Campus in Baillarguet, Montpellier, France; Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, Rafael Zubieta #1889, Miraflores, Casilla M-10019, La Paz, Bolivia
| | - Etienne Waleckx
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - Stéphanie Depickère
- INTERTRYP, CIRAD, IRD, TA A-17/G, International Campus in Baillarguet, Montpellier, France; Instituto Nacional de Laboratorios de Salud (INLASA), Laboratorio de Entomología Médica, Rafael Zubieta #1889, Miraflores, Casilla M-10019, La Paz, Bolivia; Grupo de Sistemas Complejos, Instituto de Investigaciones Físicas, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Victor Sosa
- INTERTRYP, CIRAD, IRD, TA A-17/G, International Campus in Baillarguet, Montpellier, France; Dirección de Recursos Naturales, Secretaria de Desarrollo Sostenible y Medio Ambiente, Gobierno Autónomo Departamental de Santa Cruz, Av. Fransisco Mora 3er Anillo interno, Zona Polanco, Mexico
| | - Christian Barnabé
- INTERTRYP, CIRAD, IRD, TA A-17/G, International Campus in Baillarguet, Montpellier, France
| | - David Gorla
- Instituto Altos Estudios Espaciales Mario Gulich, Universidad Nacional Córdoba-CONAE, Ruta C45 Km 8, Falda del Cañete, 5187 Córdoba, Argentina
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Abstract
Urease from Canavalia ensiformis seeds was the first enzyme ever to be crystallized, in 1926. These proteins, found in plants, bacteria and fungi, present different biological properties including catalytic hydrolysis of urea, and also enzyme-independent activities, such as induction of exocytosis, pro-inflammatory effects, neurotoxicity, antifungal and insecticidal properties. Urease is toxic to insects and fungi per se but part of this toxicity relies on an internal peptide (~11 kDa), which is released upon digestion of the protein by insect enzymes. A recombinant form of this peptide, called jaburetox (JBTX), was constructed using jbureII gene as a template. The peptide exhibits liposome disruption properties, and insecticidal and fungicidal activities. Here we review the known biological properties activities of JBTX, and comment on new ones not yet fully characterized. JBTX was able to cause mortality of Aedes aegypti larvae in a feeding assay whereas in a dose as low as of 0.1 μg it provoked death of Triatoma infestans bugs. JBTX (10−5–10−6 M) inhibits the growth of E. coli, P. aeruginosa and B. cereus after 24 h incubation. Multilamellar liposomes interacting with JBTX undergo reorganization of the membrane’s lipids as detected by small angle X-ray scattering (SAXS) studies. Encapsulating JBTX into lipid nanoparticles led to an increase of the peptide’s antifungal activity. Transgenic tobacco and sugarcane plants expressing the insecticidal peptide JBTX, showed increased resistance to attack of the insect pests Spodoptera frugiperda, Diatraea saccharalis and Telchin licus licus. Many questions remain unanswered; however, so far, JBTX has shown to be a versatile peptide that can be used against various insect and fungus species, and in new bacterial control strategies.
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Affiliation(s)
- Arlete Beatriz Becker-Ritt
- Graduate Program in Cellular and Molecular Biology Applied to Health, Lutheran University of Brazil (ULBRA), Canoas, RS Brazil
| | - Camila Saretta Portugal
- Graduate Program in Cellular and Molecular Biology Applied to Health, Lutheran University of Brazil (ULBRA), Canoas, RS Brazil
| | - Célia Regina Carlini
- Brain Institute (Instituto do Cérebro-INSCER), Pontifical Catholic University of Rio Grande do Sul (PUCRS), Porto Alegre, RS Brazil
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Gürtler RE, Yadon ZE. Eco-bio-social research on community-based approaches for Chagas disease vector control in Latin America. Trans R Soc Trop Med Hyg 2015; 109:91-8. [PMID: 25604759 PMCID: PMC4299528 DOI: 10.1093/trstmh/tru203] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
This article provides an overview of three research projects which designed and implemented innovative interventions for Chagas disease vector control in Bolivia, Guatemala and Mexico. The research initiative was based on sound principles of community-based ecosystem management (ecohealth), integrated vector management, and interdisciplinary analysis. The initial situational analysis achieved a better understanding of ecological, biological and social determinants of domestic infestation. The key factors identified included: housing quality; type of peridomestic habitats; presence and abundance of domestic dogs, chickens and synanthropic rodents; proximity to public lights; location in the periphery of the village. In Bolivia, plastering of mud walls with appropriate local materials and regular cleaning of beds and of clothes next to the walls, substantially decreased domestic infestation and abundance of the insect vector Triatoma infestans. The Guatemalan project revealed close links between house infestation by rodents and Triatoma dimidiata, and vector infection with Trypanosoma cruzi. A novel community-operated rodent control program significantly reduced rodent infestation and bug infection. In Mexico, large-scale implementation of window screens translated into promising reductions in domestic infestation. A multi-pronged approach including community mobilisation and empowerment, intersectoral cooperation and adhesion to integrated vector management principles may be the key to sustainable vector and disease control in the affected regions.
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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
| | - Zaida E Yadon
- Communicable Diseases Department, Pan American Health Organization, Washington, D.C., USA
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23
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Sommerfeld J, Kroeger A. Innovative community-based vector control interventions for improved dengue and Chagas disease prevention in Latin America: introduction to the special issue. Trans R Soc Trop Med Hyg 2015; 109:85-8. [PMID: 25604757 PMCID: PMC4299521 DOI: 10.1093/trstmh/tru176] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Johannes Sommerfeld
- Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization (WHO), Geneva, Switzerland
| | - Axel Kroeger
- Special Programme for Research and Training in Tropical Diseases (TDR), World Health Organization (WHO), Geneva, Switzerland Liverpool School of Tropical Medicine, Liverpool, UK
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24
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Kaplinski M, Jois M, Galdos-Cardenas G, Rendell VR, Shah V, Do RQ, Marcus R, Pena MSB, Abastoflor MDC, LaFuente C, Bozo R, Valencia E, Verastegui M, Colanzi R, Gilman RH, Bern C. Sustained Domestic Vector Exposure Is Associated With Increased Chagas Cardiomyopathy Risk but Decreased Parasitemia and Congenital Transmission Risk Among Young Women in Bolivia. Clin Infect Dis 2015; 61:918-26. [PMID: 26063720 DOI: 10.1093/cid/civ446] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 06/02/2015] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND We studied women and their infants to evaluate risk factors for congenital transmission and cardiomyopathy in Trypanosoma cruzi-infected women. METHODS Women provided data and blood for serology and quantitative polymerase chain reaction (PCR). Infants of infected women had blood tested at 0 and 1 month by microscopy, PCR and immunoblot, and serology at 6 and 9 months. Women underwent electrocardiography (ECG). RESULTS Of 1696 women, 456 (26.9%) were infected; 31 (6.8%) transmitted T. cruzi to their infants. Women who transmitted had higher parasite loads than those who did not (median, 62.0 [interquartile range {IQR}, 25.8-204.8] vs 0.05 [IQR, 0-29.6]; P < .0001). Transmission was higher in twin than in singleton births (27.3% vs 6.4%; P = .04). Women who had not lived in infested houses transmitted more frequently (9.7% vs 4.6%; P = .04), were more likely to have positive results by PCR (65.5% vs 33.9%; P < .001), and had higher parasite loads than those who had lived in infested houses (median, 25.8 [IQR, 0-64.1] vs 0 [IQR, 0-12.3]; P < .001). Of 302 infected women, 28 (9.3%) had ECG abnormalities consistent with Chagas cardiomyopathy; risk was higher for older women (odds ratio [OR], 1.06 [95% confidence interval {CI}, 1.01-1.12] per year) and those with vector exposure (OR, 3.7 [95% CI, 1.4-10.2]). We observed a strong dose-response relationship between ECG abnormalities and reported years of living in an infested house. CONCLUSIONS We hypothesize that repeated vector-borne infection sustains antigen exposure and the consequent inflammatory response at a higher chronic level, increasing cardiac morbidity, but possibly enabling exposed women to control parasitemia in the face of pregnancy-induced Th2 polarization.
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Affiliation(s)
- Michelle Kaplinski
- Department of Cardiology, Children's Hospital of Philadelphia, Pennsylvania
| | - Malasa Jois
- Division of Internal Medicine, Brown University, Providence, Rhode Island
| | - Gerson Galdos-Cardenas
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland Universidad Católica Boliviana, Santa Cruz, Plurinational State of Bolivia
| | | | - Vishal Shah
- Saint Louis University School of Medicine, Missouri
| | - Rose Q Do
- Department of Cardiology, University of Colorado, Denver
| | - Rachel Marcus
- Department of Cardiology, Washington Hospital Center, Washington, District of Columbia
| | | | | | | | - Ricardo Bozo
- Camiri Municipal Hospital, Camiri, Plurinational State of Bolivia
| | - Edward Valencia
- Laboratorio de Investigación en Enfermedades Infecciosas, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Manuela Verastegui
- Laboratorio de Investigación en Enfermedades Infecciosas, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Rony Colanzi
- Universidad Católica Boliviana, Santa Cruz, Plurinational State of Bolivia
| | - Robert H Gilman
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland
| | - Caryn Bern
- Department of Epidemiology and Biostatistics, University of California, San Francisco School of Medicine
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