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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: 0] [Impact Index Per Article: 0] [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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Dorn PL, Monroy MC, Stevens L. Sustainable, integrated control of native vectors: The case of Chagas disease in Central America. FRONTIERS IN TROPICAL DISEASES 2022. [DOI: 10.3389/fitd.2022.971000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Despite successes in reducing transmission, Chagas disease (American trypanosomiasis) remains the greatest economic burden of any parasitic disease in Latin America afflicting mostly the poor and further contributing to poverty. We review a long-term (2001-2022), integrated Ecohealth approach that addresses sustainable development goals to reduce risk of Chagas transmission by the main native vector in Central America, Triatoma dimidiata, s.l. The basis of the Ecohealth intervention was the identification of the risk factors for house infestation, an understanding of and collaboration with local communities, and genetic and proteomic studies that revealed the epidemiology and mechanisms of the rapid reinfestation seen following insecticide application. We review the development of this approach from a pilot project in two Guatemalan villages, to an expanded initiative across three countries with vastly different ecology, cultures, and municipal organization, and finally development of a multi-institutional, large-scale project to develop a strategy to tackle the remaining hot spots in Central America. This integrated Ecohealth approach resulted in reduced risk of transmission as measured by a sustained decrease in house infestation without further use of insecticides, a reduction in vectors with human blood meals and the Chagas parasite, as well as other health and economic benefits. We discuss lessons learned and how this approach could be applied to other vector-borne diseases.
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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: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [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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Pereira FM, Penados D, Dorn PL, Alcántara B, Monroy MC. The long-term impact of an Ecohealth intervention: Entomological data suggest the interruption of Chagas disease transmission in southeastern Guatemala. Acta Trop 2022; 235:106655. [PMID: 35977598 DOI: 10.1016/j.actatropica.2022.106655] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/10/2022] [Accepted: 08/13/2022] [Indexed: 11/01/2022]
Abstract
Triatoma dimidiata is the main vector of Chagas disease in southern Mexico, Central America and northern South America. As a native vector, it moves readily among domestic, peri-domestic and sylvatic environments, making it difficult to control only using insecticide as this requires regular application, and re-infestation frequently occurs. Other social innovation alternatives such as those based on Ecohealth principles can be used to tackle the dynamics of the disease in an integral way. We asked whether an Ecohealth intervention, implemented beginning in 2001 in a highly infested village, 41.8%, in southeastern Guatemala, was sustainable in the long term. This intervention included initial insecticide treatments, followed by making low-cost house improvements to eliminate transmission risk factors such as repairing cracked walls, covering dirt floors with a cement-like substance and moving domestic animals outside. We assessed the long-term sustainability through entomological and house condition surveys, as well as an analysis of community satisfaction. We found over a 19-year period, infestation with T. dimidiata was reduced to 2.2% and maintained at a level below the level (8%) where vector transmission is unlikely. This long-term maintenance of low infestation coincided with a large proportion of villagers (88.6%) improving their houses and completing other aspects of the Ecohealth approach to maintain the village at low risk for Chagas transmission. There was unanimous satisfaction among the villagers with their houses, following improvements using the Ecohealth method, which likely played a role in the long-term persistence of the modifications. Although the infestation has remained low, 11 years following the last intervention and as the population grew there has been an increase in the proportion of "at-risk" houses, to 33%, pointing out the necessity of maintaining vigilance. The Ecohealth approach is a low-cost, sustainable approach for the long-term control of vector-borne Chagas disease. We recommend this approach including ongoing community monitoring and institutional response for the long-term, integrated control of Chagas disease.
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Affiliation(s)
- Fredy Manolo Pereira
- Laboratory of Applied Entomology and Parasitology, Faculty of Chemical Sciences and Pharmacy, University of San Carlos of Guatemala, Guatemala.
| | - Daniel Penados
- Laboratory of Applied Entomology and Parasitology, Faculty of Chemical Sciences and Pharmacy, University of San Carlos of Guatemala, Guatemala
| | - Patricia L Dorn
- Department of Biological Sciences, Loyola University New Orleans, New Orleans, Louisiana, United States
| | - Belter Alcántara
- Laboratory of Applied Entomology and Parasitology, Faculty of Chemical Sciences and Pharmacy, University of San Carlos of Guatemala, Guatemala
| | - María Carlota Monroy
- Laboratory of Applied Entomology and Parasitology, Faculty of Chemical Sciences and Pharmacy, University of San Carlos of Guatemala, Guatemala
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de Arias AR, Monroy C, Guhl F, Sosa-Estani S, Santos WS, Abad-Franch F. Chagas disease control-surveillance in the Americas: the multinational initiatives and the practical impossibility of interrupting vector-borne Trypanosoma cruzi transmission. Mem Inst Oswaldo Cruz 2022; 117:e210130. [PMID: 35830010 PMCID: PMC9261920 DOI: 10.1590/0074-02760210130] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 11/21/2022] Open
Abstract
Chagas disease (CD) still imposes a heavy burden on most Latin American countries. Vector-borne and mother-to-child transmission cause several thousand new infections per year, and at least 5 million people carry Trypanosoma cruzi. Access to diagnosis and medical care, however, is far from universal. Starting in the 1990s, CD-endemic countries and the Pan American Health Organization-World Health Organization (PAHO-WHO) launched a series of multinational initiatives for CD control-surveillance. An overview of the initiatives’ aims, achievements, and challenges reveals some key common themes that we discuss here in the context of the WHO 2030 goals for CD. Transmission of T. cruzi via blood transfusion and organ transplantation is effectively under control. T. cruzi, however, is a zoonotic pathogen with 100+ vector species widely spread across the Americas; interrupting vector-borne transmission seems therefore unfeasible. Stronger surveillance systems are, and will continue to be, needed to monitor and control CD. Prevention of vertical transmission demands boosting current efforts to screen pregnant and childbearing-aged women. Finally, integral patient care is a critical unmet need in most countries. The decades-long experience of the initiatives, in sum, hints at the practical impossibility of interrupting vector-borne T. cruzi transmission in the Americas. The concept of disease control seems to provide a more realistic description of what can in effect be achieved by 2030.
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Affiliation(s)
| | - Carlota Monroy
- Universidad de San Carlos, Laboratorio de Entomología y Parasitología Aplicadas, Ciudad de Guatemala, Guatemala
| | - Felipe Guhl
- Universidad de los Andes, Facultad de Ciencias, Centro de Investigaciones en Microbiología y Parasitología Tropical, Bogotá, Colombia
| | - Sergio Sosa-Estani
- Drugs for Neglected Diseases initiative Latin America, Rio de Janeiro, RJ, Brasil.,Centro de Investigaciones en Epidemiología y Salud Pública, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Walter Souza Santos
- Ministério da Saúde, Secretaria de Vigilância em Saúde, Instituto Evandro Chagas, Laboratório de Epidemiologia das Leishmanioses, Ananindeua, PA, Brasil
| | - Fernando Abad-Franch
- Universidade de Brasília, Faculdade de Medicina, Núcleo de Medicina Tropical, Brasília, DF, Brasil
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Case BKM, Young JG, Penados D, Monroy C, Hébert-Dufresne L, Stevens L. Spatial epidemiology and adaptive targeted sampling to manage the Chagas disease vector Triatoma dimidiata. PLoS Negl Trop Dis 2022; 16:e0010436. [PMID: 35653307 PMCID: PMC9162375 DOI: 10.1371/journal.pntd.0010436] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 04/20/2022] [Indexed: 11/18/2022] Open
Abstract
Widespread application of insecticide remains the primary form of control for Chagas disease in Central America, despite only temporarily reducing domestic levels of the endemic vector Triatoma dimidiata and having little long-term impact. Recently, an approach emphasizing community feedback and housing improvements has been shown to yield lasting results. However, the additional resources and personnel required by such an intervention likely hinders its widespread adoption. One solution to this problem would be to target only a subset of houses in a community while still eliminating enough infestations to interrupt disease transfer. Here we develop a sequential sampling framework that adapts to information specific to a community as more houses are visited, thereby allowing us to efficiently find homes with domiciliary vectors while minimizing sampling bias. The method fits Bayesian geostatistical models to make spatially informed predictions, while gradually transitioning from prioritizing houses based on prediction uncertainty to targeting houses with a high risk of infestation. A key feature of the method is the use of a single exploration parameter, α, to control the rate of transition between these two design targets. In a simulation study using empirical data from five villages in southeastern Guatemala, we test our method using a range of values for α, and find it can consistently select fewer homes than random sampling, while still bringing the village infestation rate below a given threshold. We further find that when additional socioeconomic information is available, much larger savings are possible, but that meeting the target infestation rate is less consistent, particularly among the less exploratory strategies. Our results suggest new options for implementing long-term T. dimidiata control. Effective public health interventions for the control and elimination of neglected tropical diseases require an efficient use of resources while still causing long-term disease reduction at the community level. To use resources to best effect, areas most in need of control efforts must be identified. However, strategies for correctly identifying these areas are rarely known due to the complex environmental, biological, and cultural factors shaping disease spread. In turn, incorrect prioritization of control targets can cause the intervention to have no lasting effect. We address this tradeoff between efficiency and efficacy by adapting control priorities throughout an intervention, targeting areas of high uncertainty during the initial stages while shifting to areas of greatest risk at later stages. In the context of controlling Triatoma dimidiata, the primary vector of Chagas disease in several countries in Latin America, our methods provide a means of targeting only a subset of homes for insecticide and housing improvements, while still reducing a village’s overall infestation rate below the critical threshold.
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Affiliation(s)
- B. K. M. Case
- Vermont Complex Systems Center, University of Vermont, Burlington, Vermont, United States of America
- Department of Computer Science, University of Vermont, Burlington, Vermont, United States of America
- * E-mail:
| | - Jean-Gabriel Young
- Vermont Complex Systems Center, University of Vermont, Burlington, Vermont, United States of America
- Department of Mathematics & Statistics, University of Vermont, Burlington, Vermont, United States of America
| | - Daniel Penados
- Laboratorio de Entomología Aplicada y Parasitología, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala
| | - Carlota Monroy
- Laboratorio de Entomología Aplicada y Parasitología, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala
| | - Laurent Hébert-Dufresne
- Vermont Complex Systems Center, University of Vermont, Burlington, Vermont, United States of America
- Department of Computer Science, University of Vermont, Burlington, Vermont, United States of America
| | - Lori Stevens
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
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Assessing risk of vector transmission of Chagas disease through blood source analysis using LC-MS/MS for hemoglobin sequence identification. PLoS One 2022; 17:e0262552. [PMID: 35073364 PMCID: PMC8786159 DOI: 10.1371/journal.pone.0262552] [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: 08/31/2021] [Accepted: 12/28/2021] [Indexed: 11/19/2022] Open
Abstract
Chagas disease is mainly transmitted by triatomine insect vectors that feed on vertebrate blood. The disease has complex domiciliary infestation patterns and parasite transmission dynamics, influenced by biological, ecological, and socioeconomic factors. In this context, feeding patterns have been used to understand vector movement and transmission risk. Recently, a new technique using Liquid chromatography tandem mass spectrometry (LC-MS/MS) targeting hemoglobin peptides has showed excellent results for understanding triatomines' feeding patterns. The aim of this study was to further develop the automated computational analysis pipeline for peptide sequence taxonomic identification, enhancing the ability to analyze large datasets data. We then used the enhanced pipeline to evaluate the feeding patterns of Triatoma dimidiata, along with domiciliary infestation risk variables, such as unkempt piles of firewood or construction material, cracks in bajareque and adobe walls and intradomiciliary animals. Our new python scripts were able to detect blood meal sources in 100% of the bugs analyzed and identified nine different species of blood meal sources. Human, chicken, and dog were the main blood sources found in 78.7%, 50.4% and 44.8% of the bugs, respectively. In addition, 14% of the bugs feeding on chicken and 15% of those feeding on dogs were captured in houses with no evidence of those animals being present. This suggests a high mobility among ecotopes and houses. Two of the three main blood sources, dog and chicken, were significantly (p < 0.05) affected by domiciliary infestation risk variables, including cracks in walls, construction material and birds sleeping in the intradomicile. This suggests that these variables are important for maintaining reproducing Triatoma dimidiata populations and that it is critical to mitigate these variables in all the houses of a village for effective control of these mobile vectors.
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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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Juarez JG, Garcia-Luna SM, Medeiros MCI, Dickinson KL, Borucki MK, Frank M, Badillo-Vargas I, Chaves LF, Hamer GL. The Eco-Bio-Social Factors That Modulate Aedes aegypti Abundance in South Texas Border Communities. INSECTS 2021; 12:insects12020183. [PMID: 33670064 PMCID: PMC7926310 DOI: 10.3390/insects12020183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/16/2021] [Accepted: 02/18/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary The Aedes aegypti mosquito is distributed worldwide and has become a major public health concern due to its proclivity for the urban environment, human feeding behavior, and ability to transmit agents of diseases such as Zika, chikungunya, and dengue. In the continental United States, the region known as the Lower Rio Grande Valley is one of the few areas with local mosquito transmission of these pathogens transmitted by Ae. aegypti. With limited resources for mosquito control in this region, understanding the ecological, biological, and social factors that affect Ae. aegypti population can help guide and improve current control efforts. We were able to observe widespread knowledge regarding Zika, but with very low importance given to mosquitoes as a problem. We found that the presence of window-mounted air conditioning units, number of windows and doors, characteristics of the property, and presence of children in the household all influenced the abundance of Ae. aegypti. The current results not only show a need for improved community engagement for increasing disease and mosquito risk awareness, but also provide risk factors that can guide current vector control activities. Abstract Aedes aegypti control requires dedicated resources that are usually scarce, limiting the reach and sustainability of vector control programs. This generates a need to focus on areas at risk of disease transmission and also understand the factors that might modulate local mosquito abundance. We evaluated the eco-bio-social factors that modulate indoor and outdoor relative abundance of female Ae. aegypti in communities of South Texas. We conducted housing quality and Knowledge Attitudes and Practices surveys in households that were part of a weekly mosquito surveillance program in November of 2017 and 2018. Our results showed widespread knowledge of mosquitoes and Zika virus by our participants. However, less than 35% considered them as serious problems in this region. The presence of window-mounted air conditioning units increased the risk of female mosquito relative abundance indoors. An increase in outdoor relative abundance was associated with larger properties and a higher number of children between 6 to 17 years of age. Interestingly, we observed that an increasing number of children <5 years of age modulated both indoor and outdoor relative abundance, with a 52% increase indoors and 30% decrease outdoors. The low perception of mosquito and disease risk highlights engagement needs for vector-borne disease prevention in this region. The identified risk factors can help guide public health officials in their efforts to reduce human and vector contact.
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Affiliation(s)
- Jose G. Juarez
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA; (S.M.G.-L.); (I.B.-V.)
- Correspondence: (J.G.J.); (G.L.H.)
| | - Selene M. Garcia-Luna
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA; (S.M.G.-L.); (I.B.-V.)
| | - Matthew C. I. Medeiros
- Pacific Biosciences Research Center, University of Hawaii at Mānoa, Honolulu, HI 96822, USA;
| | - Katherine L. Dickinson
- Colorado School of Public Health, Department of Environmental and Occupational Health, Aurora, CO 80045, USA;
| | - Monica K. Borucki
- Lawrence Livermore National Laboratory, Livermore, CA 94550, USA; (M.K.B.); (M.F.)
| | - Matthias Frank
- Lawrence Livermore National Laboratory, Livermore, CA 94550, USA; (M.K.B.); (M.F.)
| | - Ismael Badillo-Vargas
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA; (S.M.G.-L.); (I.B.-V.)
| | - Luis F. Chaves
- Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud (INCIENSA), Tres Ríos 4-2250, Cartago, Costa Rica;
| | - Gabriel L. Hamer
- Department of Entomology, Texas A&M University, College Station, TX 77843, USA; (S.M.G.-L.); (I.B.-V.)
- Correspondence: (J.G.J.); (G.L.H.)
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Penados D, Pineda J, Catalan M, Avila M, Stevens L, Agreda E, Monroy C. Infestation dynamics of Triatoma dimidiata in highly deforested tropical dry forest regions of Guatemala. Mem Inst Oswaldo Cruz 2020; 115:e200203. [PMID: 33146245 PMCID: PMC7592497 DOI: 10.1590/0074-02760200203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 10/05/2020] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Deforestation, driven by anthropogenic change in land use, influences the behaviour and abundance of vector-borne diseases. For various species of Chagas disease vectors, there is evidence that change in land use affects population density and abundance. Triatoma dimidiata is the most important Chagas vector in Guatemala, and at least one million people live in T. dimidiata endemic areas; however, infestation dynamics vary among regions, from high infestation with all life stages to low seasonal infestation by sylvatic adults. OBJECTIVES The aim of this study was to evaluate how land-use, combined with domiciliary risk factors, influences the infestation dynamics of T. dimidiata for four villages in a dry forest region with a strong deforestation history. METHODS Land use, measured with drone and satellite images, was classified into four categories (houses, monocultures and pastures, woodland and shrubland, and bare soil). Domiciliary risk factors and infestation were assessed through entomological surveys. Statistical analyses compared infestation indices and the ability of land use and domiciliary risk factors to explain infestation. FINDINGS Two villages had significantly higher infestation (26 and 30% vs. 5 and 6%), yet all villages had high colonisation (71-100% of infested houses had immature insects), with no significant difference among them. Because of the high level of deforestation across the study area, land use was not related to infestation; however, domiciliary risk factors were. A model based on four weighted domiciliary risk factors (adobe or bajareque walls, intradomicile animals, intradomicile clutter, and dirt floors) explains the infestation risk. MAIN CONCLUSIONS Because almost all infested houses have reproducing populations in this deforested dry forest region and statistical analysis identified the domiciliary risk factors for infestation, intermediate and long-term control of Chagas disease vectors in this region requires management of these risk factors.
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Affiliation(s)
- Daniel Penados
- Universidad de San Carlos de Guatemala, Laboratorio de Entomología Aplicada y Parasitología, Ciudad de Guatemala, Guatemala
| | - José Pineda
- Universidad de San Carlos de Guatemala, Laboratorio de Entomología Aplicada y Parasitología, Ciudad de Guatemala, Guatemala
| | - Michelle Catalan
- Universidad de San Carlos de Guatemala, Facultad de Ciencias Químicas y Farmacia, Escuela de Biología, Ciudad de Guatemala, Guatemala
| | - Miguel Avila
- Universidad de San Carlos de Guatemala, Centros de Estudios Conservacionistas, Ciudad de Guatemala, Guatemala
| | - Lori Stevens
- University of Vermont, Department of Biology, Burlington, VT, USA
| | - Emmanuel Agreda
- Universidad de San Carlos de Guatemala, Laboratorio de Entomología Aplicada y Parasitología, Ciudad de Guatemala, Guatemala
| | - Carlota Monroy
- Universidad de San Carlos de Guatemala, Laboratorio de Entomología Aplicada y Parasitología, Ciudad de Guatemala, Guatemala
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Hanley JP, Rizzo DM, Stevens L, Helms Cahan S, Dorn PL, Morrissey LA, Rodas AG, Orantes LC, Monroy C. Novel Evolutionary Algorithm Identifies Interactions Driving Infestation of Triatoma dimidiata, a Chagas Disease Vector. Am J Trop Med Hyg 2020; 103:735-744. [PMID: 32524965 DOI: 10.4269/ajtmh.18-0733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Chagas disease is a lethal, neglected tropical disease. Unfortunately, aggressive insecticide-spraying campaigns have not been able to eliminate domestic infestation of Triatoma dimidiata, the native vector in Guatemala. To target interventions toward houses most at risk of infestation, comprehensive socioeconomic and entomologic surveys were conducted in two towns in Jutiapa, Guatemala. Given the exhaustively large search space associated with combinations of risk factors, traditional statistics are limited in their ability to discover risk factor interactions. Two recently developed statistical evolutionary algorithms, specifically designed to accommodate risk factor interactions and heterogeneity, were applied to this large combinatorial search space and used in tandem to identify sets of risk factor combinations associated with infestation. The optimal model includes 10 risk factors in what is known as a third-order disjunctive normal form (i.e., infested households have chicken coops AND deteriorated bedroom walls OR an accumulation of objects AND dirt floors AND total number of occupants ≥ 5 AND years of electricity ≥ 5 OR poor hygienic condition ratings AND adobe walls AND deteriorated walls AND dogs). Houses with dirt floors and deteriorated walls have been reported previously as risk factors and align well with factors currently targeted by Ecohealth interventions to minimize infestation. However, the tandem evolutionary algorithms also identified two new socioeconomic risk factors (i.e., households having many occupants and years of electricity ≥ 5). Identifying key risk factors may help with the development of new Ecohealth interventions and/or reduce the survey time needed to identify houses most at risk.
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Affiliation(s)
- John P Hanley
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, Vermont
| | - Donna M Rizzo
- Department of Civil and Environmental Engineering, University of Vermont, Burlington, Vermont
| | - Lori Stevens
- Department of Biology, University of Vermont, Burlington, Vermont
| | - Sara Helms Cahan
- Department of Biology, University of Vermont, Burlington, Vermont
| | - Patricia L Dorn
- Department of Biological Sciences, Loyola University New Orleans, New Orleans, Louisiana
| | - Leslie A Morrissey
- Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, Vermont
| | - Antonieta Guadalupe Rodas
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala
| | - Lucia C Orantes
- Rubenstein School of Environment and Natural Resources, University of Vermont, Burlington, Vermont
| | - Carlota Monroy
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala
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Coyle AH, Berrian AM, van Rooyen J, Bagnol B, Smith MH. Gender Roles and One Health Risk Factors at the Human-Livestock-Wildlife Interface, Mpumalanga Province, South Africa. ECOHEALTH 2020; 17:233-247. [PMID: 32285224 DOI: 10.1007/s10393-020-01478-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 01/28/2020] [Accepted: 01/30/2020] [Indexed: 06/11/2023]
Abstract
Gender sensitivity in health promotion has been widely recommended, yet attention to gender roles and gender-disaggregated studies is often lacking in disease research and public health intervention planning. In the rural Mnisi community of Mpumalanga, South Africa, where zoonotic pathogens are known to contribute to acute febrile illness, community and household tasks may increase an individual's risk of exposure, and these tasks are likely to be influenced by gender. This study described the roles and responsibilities of community residents, specifically those that have been identified as critical control points for infectious pathogen exposure, by gender. Male gender-typed tasks included those associated with livestock and poultry husbandry, hunting and slaughtering wildlife, and rodent control. Female gender-typed tasks included animal-sourced food preparation, domestic cleaning and maintenance, and caregiving to children and ill family members. Given the gender-specific nature of these tasks, potential pathogen exposure and transmission patterns of infectious diseases may be also gender specific. These data can inform the development and revision of health promotion strategies, such as the community-based One Health Training and Leadership program, prioritizing outcomes for male and female participants alike. Gender-disaggregated analysis is recommended for effective risk mitigation and community-wide health promotion using a One Health approach.
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Affiliation(s)
- Allison H Coyle
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Amanda M Berrian
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, 1920 Coffey Road, A190 Sisson Hall, Columbus, OH, 43210, USA.
| | - Jacques van Rooyen
- Centre for Veterinary Wildlife Studies, Faculty of Veterinary Science, University of Pretoria, Hans Hoheisen Wildlife Research Station, Orpen Gate, Kruger National Park, South Africa
- Conservation South Africa, Cape Town, South Africa
| | - Brigitte Bagnol
- Department of Anthropology, University of Witwatersrand, Johannesburg, South Africa
| | - Martin H Smith
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA, USA
- Department of Human Ecology, College of Agriculture and Environmental Sciences, University of California, Davis, CA, USA
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13
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Integrated vector control of Chagas disease in Guatemala: a case of social innovation in health. Infect Dis Poverty 2020; 9:25. [PMID: 32284071 PMCID: PMC7155339 DOI: 10.1186/s40249-020-00639-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 02/17/2020] [Indexed: 11/24/2022] Open
Abstract
Background Improved access to health care and quality of services require integrated efforts and innovations, including community empowerment and participation in transformation processes. Chagas disease is a neglected tropical disease that is generally controlled by insecticide spraying. To achieve community empowerment in a health program, actions for social innovations may include: community-based research, interdisciplinary and intersectoral participation, community perception of direct benefits and participation in health or environmental improvements. The aim of this study was to describe and analyze the processes by which an interdisciplinary team, in collaboration with communities of Comapa, Guatemala, developed an effective solution to address the risk for Chagas disease. Methods A qualitative study involving interviews semi-structured and direct observation was conducted using a case study approach to describe and understand the community-based research and intervention process developed by researchers from the Laboratory of Applied Entomology and Parasitology of the Universidad de San Carlos of Guatemala (Laboratorio de Entomologia y Parasitologia Aplicada). Nine interviews were conducted with the investigators, innovators, members of the community in which the intervention had been implemented. NVivo software (version 12) was used for the emergent coding and analysis of the interviews. Results Processes of social transformation were evident within households, and the communities that transcended the mere improvement of walls and floors. New social dynamics that favored the household economy and conditions of hygiene and home care that positively impacted the health of the community. We describe how the integration of criteria of social innovation into a home improvement strategy for Chagas disease control, can generate processes of transformation in health by considering sociocultural conditions, encouraging dialogue between public health approaches and traditional practices. We identify and discuss processes for Social Innovations in Health and identify their potential in improving community health in Latin America. Conclusions When social innovation criteria are included in a health control initiative, the community-based research and the interdisciplinary and intersectoral participation facilitate the implementation of the control strategy, the perceived benefits by the community and its empowerment to sustain and share the strategy. The case study provided understanding of the intersectoral and interdisciplinary dynamics in particular contexts, and documented the relevance of innovation criteria in health processes.
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14
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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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15
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Cahan SH, Orantes LC, Wallin KF, Hanley JP, Rizzo DM, Stevens L, Dorn PL, Rodas A, Monroy C. Residual survival and local dispersal drive reinfestation by Triatoma dimidiata following insecticide application in Guatemala. INFECTION GENETICS AND EVOLUTION 2019; 74:104000. [DOI: 10.1016/j.meegid.2019.104000] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 08/08/2019] [Accepted: 08/09/2019] [Indexed: 11/30/2022]
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16
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Keller JI, Lima-Cordón R, Monroy MC, Schmoker AM, Zhang F, Howard A, Ballif BA, Stevens L. Protein mass spectrometry detects multiple bloodmeals for enhanced Chagas disease vector ecology. INFECTION GENETICS AND EVOLUTION 2019; 74:103998. [PMID: 31401306 DOI: 10.1016/j.meegid.2019.103998] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/22/2019] [Accepted: 08/07/2019] [Indexed: 10/26/2022]
Abstract
Chagas disease, a neglected tropical disease endemic in Latin America, is caused by the protozoan parasite Trypanosoma cruzi and is responsible for significant health impacts, especially in rural communities. The parasite is transmitted by insect vectors in the Triatominae subfamily and due to lack of vaccines and limited treatment options, vector control is the main way of controlling the disease. Knowing what vectors are feeding on directly enhances our understanding of the ecology and biology of the different vector species and can potentially aid in engaging communities in active disease control, a concept known as Ecohealth management. We evaluated bloodmeals in rural community, house-caught insect vectors previously evaluated for bloodmeals via DNA analysis as part of a larger collaborative project from three countries in Central America, including Guatemala. In addition to identifying bloodmeals in 100% of all samples using liquid chromatography tandem mass spectrometry (LC-MS/MS) (n = 50), strikingly for 53% of these samples there was no evidence of a recent bloodmeal by DNA-PCR. As individual vectors often feed on multiple sources, we developed an enhanced detection pipeline, and showed the ability to quantify a bloodmeal using stable-isotope-containing synthetic references peptides, a first step in further exploration of species-specific bloodmeal composition. Furthermore, we show that a lower resolution mass spectrometer is sufficient to correctly identify taxa from bloodmeals, an important and strong attribute of our LC-MS/MS-based method, opening the door to using proteomics in countries where Chagas disease is endemic.
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Affiliation(s)
- Judith I Keller
- Department of Biology, University of Vermont, Burlington, VT, United States
| | - Raquel Lima-Cordón
- Department of Biology, University of Vermont, Burlington, VT, United States
| | - M Carlota Monroy
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Facultad de Ciencias Químicas y Farmacia, Universidad de San Carlos de Guatemala, Edificio T-10 Ciudad Universitaria Zona 12, Ciudad de Guatemala, Guatemala; Department of Biology, University of Vermont, Burlington, VT, United States
| | - Anna M Schmoker
- Department of Biology, University of Vermont, Burlington, VT, United States
| | - Fan Zhang
- Department of Biology, University of Vermont, Burlington, VT, United States
| | - Alan Howard
- Statistical Software Support and Consulting Services, University of Vermont, Burlington, VT, United States
| | - Bryan A Ballif
- Department of Biology, University of Vermont, Burlington, VT, United States.
| | - Lori Stevens
- Department of Biology, University of Vermont, Burlington, VT, United States.
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Francis D, Cohen G, Bhatt J, Brask C, Devnani M, Surgenor G. How healthcare can help heal communities and the planet. BMJ 2019; 365:l2398. [PMID: 31209177 PMCID: PMC6571714 DOI: 10.1136/bmj.l2398] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The gains from healthcare are often undermined by the sector’s contributions to social inequity and environmental damage, but it doesn’t have to be that way argue Damon Francis and colleagues
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Affiliation(s)
| | - Gary Cohen
- Health Care Without Harm, Boston, MA, USA
| | - Jay Bhatt
- Health Research and Educational Trust, Chicago, IL, USA
| | | | - Mahesh Devnani
- Department of Hospital Administration, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Gael Surgenor
- Southern Initiative, Auckland Council, Auckland, New Zealand
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18
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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. Chagas disease (CD) is transmitted by triatomine insects, vectors of the parasite Trypanosoma cruzi. Triatomines are commonly found in precariously constructed homes where they remain hidden in cracks and crevices during the day and feed on blood sources at night. Due to this association between living environments and disease, multiple control programs have implemented some form of home improvement as a CD preventive measure. Using Healthy Homes for Healthy Living (HHHL)—a strategy focused on home improvement and health promotion activities conducted through community partnerships—as reference, this study was designed to explore factors affecting sustainability of such models of disease control. Research participants were selected from families that have participated in construction projects implemented by HHHL between 2013 and 2016 in three rural communities of southern Ecuador. Following qualitative methodological approaches, data were collected through interviews, participant observation, informal conversations and document analysis. Our results indicate that home improvement, when conducted under systemic approaches to disease prevention, can lead to a comprehensive idea of health expressed as individual physical protection, as well as a emotional, economic, and social wellbeing at household and community levels. Sustainability of this intervention is linked to an increased sense of agency around disease prevention in local families.
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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
- * E-mail:
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19
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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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Friedson-Ridenour S, Dutcher TV, Calderon C, Brown LD, Olsen CW. Gender Analysis for One Health: Theoretical Perspectives and Recommendations for Practice. ECOHEALTH 2019; 16:306-316. [PMID: 31016438 DOI: 10.1007/s10393-019-01410-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/20/2018] [Accepted: 02/12/2019] [Indexed: 05/14/2023]
Abstract
One health emphasizes the interdependent health of humans, animals, and their shared environments and shows promise as an integrated, equitable transdisciplinary approach to important ecohealth issues. Notably, research or programming explicitly examining the intersection of gender and one health is limited, although females represent half of the human population and play important roles in human and animal health around the world. Recognizing these gaps, scholars from the University of Wisconsin-Madison in collaboration with United States Department of Agriculture convened a consultative workshop, "Women and One Health," in 2016. This paper outlines the workshop methods and highlights outcomes toward shared terminology and integration of frameworks from one health, gender analysis, and women in agriculture. Further, recommendations for education, policy, and service delivery at the intersection of women's empowerment and one health are offered as important efforts toward the dual goals of gender equality and sustainable health of humans, animals, and their shared ecosystems.
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Affiliation(s)
- Sophia Friedson-Ridenour
- Department of Educational Policy Studies, University of Wisconsin-Madison, Madison, WI, USA
- Global Health Institute, University of Wisconsin-Madison, Madison, WI, USA
- 4W Initiative - Women and Wellbeing in Wisconsin and the World, University of Wisconsin-Madison, Madison, WI, USA
| | - Tracey V Dutcher
- United States Department of Agriculture, One Health Coordination Center, Animal and Plant Health Inspection Service, St. Paul, MN, USA
| | - Claudia Calderon
- 4W Initiative - Women and Wellbeing in Wisconsin and the World, University of Wisconsin-Madison, Madison, WI, USA
- College of Agricultural and Life Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Lori DiPrete Brown
- Global Health Institute, University of Wisconsin-Madison, Madison, WI, USA
- 4W Initiative - Women and Wellbeing in Wisconsin and the World, University of Wisconsin-Madison, Madison, WI, USA
| | - Christopher W Olsen
- Global Health Institute, University of Wisconsin-Madison, Madison, WI, USA.
- 4W Initiative - Women and Wellbeing in Wisconsin and the World, University of Wisconsin-Madison, Madison, WI, USA.
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA.
- School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI, USA.
- Health Sciences Learning Center - Room 4276, Global Health Institute and Office of Global Health, School of Medicine and Public Health, 750 Highland Avenue, Madison, WI, 53705, USA.
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Chagas Disease in Central America: Recent Findings and Current Challenges in Vector Ecology and Control. CURRENT TROPICAL MEDICINE REPORTS 2019. [DOI: 10.1007/s40475-019-00175-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Juarez JG, Pennington PM, Bryan JP, Klein RE, Beard CB, Berganza E, Rizzo N, Cordon-Rosales C. A decade of vector control activities: Progress and limitations of Chagas disease prevention in a region of Guatemala with persistent Triatoma dimidiata infestation. PLoS Negl Trop Dis 2018; 12:e0006896. [PMID: 30399143 PMCID: PMC6239342 DOI: 10.1371/journal.pntd.0006896] [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: 02/21/2018] [Revised: 11/16/2018] [Accepted: 10/03/2018] [Indexed: 01/15/2023] Open
Abstract
INTRODUCTION Chagas disease, a neglected tropical disease that affects millions of Latin Americans, has been effectively controlled in Guatemala after multiple rounds of indoor residual insecticide spraying (IRS). However, a few foci remain with persistent Triatoma dimidiata infestation. One such area is the municipality of Comapa, Department of Jutiapa, in the southeastern region of Guatemala, where control interventions appear less effective. We carried out three cross sectional entomological and serological surveys in Comapa to evaluate a decade of vector control activities. Baseline serological (1999) and entomological (2001-2) surveys were followed by three rounds of insecticide applications (2003-2005) and intermittent focal spraying of infested houses, until approximately 2012. Household inspections to determine entomological indices and construction materials were conducted in 2001, 2007 and 2011. Seroprevalence surveys were conducted in school-age children in 1999, 2007 and 2015, and in women of child bearing age (15-44 years) only in 2015. After multiple rounds of indoor residual sprayings (IRS), the infestation index decreased significantly from 39% (2001-2) to 27% (2011). Household construction materials alone predicted <10% of infested houses. Chagas seroprevalence in Comapa declined in school-aged children by 10-fold, from 10% (1999) to 1% (2015). However, seroprevalence in women of child bearing age remains >10%. CONCLUSION After a decade of vector control activities in Comapa, there is evidence of significantly reduced transmission. However, the continued risk for vector-borne and congenital transmission pose a threat to the 2022 Chagas disease elimination goal. Systematic integrated vector control and improved Chagas disease screening and treatment programs for congenital and vector-borne disease are needed to reach the elimination goal in regions with persistent vector infestation.
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Affiliation(s)
- Jose G. Juarez
- Center of Health Studies, Universidad del Valle de Guatemala, Ciudad de Guatemala, Guatemala
| | - Pamela M. Pennington
- Center of Biotechnology, Universidad del Valle de Guatemala, Ciudad de Guatemala, Guatemala
| | - Joe P. Bryan
- Centers for Disease Control and Prevention Central America Regional Office, Guatemala City, Guatemala
- Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Robert E. Klein
- Visiting Investigator, Universidad del Valle de Guatemala, Ciudad de Guatemala, Guatemala
| | - Charles B. Beard
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America
| | - Elsa Berganza
- Area de Salud de Jutiapa, Ministerio de Salud Pública y Asistencia Social de Guatemala, Guatemala
| | - Nidia Rizzo
- Center of Health Studies, Universidad del Valle de Guatemala, Ciudad de Guatemala, Guatemala
| | - Celia Cordon-Rosales
- Center of Health Studies, Universidad del Valle de Guatemala, Ciudad de Guatemala, Guatemala
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Lima-Cordón RA, Stevens L, Solórzano Ortíz E, Rodas GA, Castellanos S, Rodas A, Abrego V, Zúniga Valeriano C, Monroy MC. Implementation science: Epidemiology and feeding profiles of the Chagas vector Triatoma dimidiata prior to Ecohealth intervention for three locations in Central America. PLoS Negl Trop Dis 2018; 12:e0006952. [PMID: 30485265 PMCID: PMC6287883 DOI: 10.1371/journal.pntd.0006952] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/10/2018] [Accepted: 10/29/2018] [Indexed: 11/19/2022] Open
Abstract
The Ecohealth strategy is a multidisciplinary data-driven approach used to improve the quality of people's lives in Chagas disease endemic areas, such as regions of Central America. Chagas is a vector-borne disease caused by the parasite Trypanosoma cruzi. In Central America, the main vector is Triatoma dimidiata. Because successful implementation of the Ecohealth approach reduced home infestation in Jutiapa department, Guatemala, it was scaled-up to three localities, one in each of three Central American countries (Texistepeque, El Salvador; San Marcos de la Sierra, Honduras and Olopa, Guatemala). As a basis for the house improvement phase of the Ecohealth program, we determined if the localities differ in the role of sylvatic, synanthropic and domestic animals in the Chagas transmission cycle by measuring entomological indices, blood meal sources and parasite infection from vectors collected in and around houses. The Polymerase Chain Reaction (PCR) with taxa specific primers to detect both, blood sources and parasite infection, was used to assess 71 T. dimidiata from Texistepeque, 84 from San Marcos de la Sierra and 568 from Olopa. Our results show that infestation (12.98%) and colonization (8.95%) indices were highest in Olopa; whereas T. cruzi prevalence was higher in Texistepeque and San Marcos de la Sierra (>40%) than Olopa (8%). The blood meal source profiles showed that in Olopa, opossum might be important in linking the sylvatic and domestic Chagas transmission cycle, whereas in San Marcos de la Sierra dogs play a major role in maintaining domestic transmission. For Texistepeque, bird was the major blood meal source followed by human. When examining the different life stages, we found that in Olopa, the proportion bugs infected with T. cruzi is higher in adults than nymphs. These findings highlight the importance of location-based recommendations for decreasing human-vector contact in the control of Chagas disease.
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Affiliation(s)
- Raquel Asunción Lima-Cordón
- The Applied Entomology and Parasitology Laboratory at Biology School, Pharmacy Faculty, San Carlos University of Guatemala, Guatemala City, Guatemala
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - Lori Stevens
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - Elizabeth Solórzano Ortíz
- The Applied Entomology and Parasitology Laboratory at Biology School, Pharmacy Faculty, San Carlos University of Guatemala, Guatemala City, Guatemala
| | - Gabriela Anaité Rodas
- The Applied Entomology and Parasitology Laboratory at Biology School, Pharmacy Faculty, San Carlos University of Guatemala, Guatemala City, Guatemala
| | - Salvador Castellanos
- The Applied Entomology and Parasitology Laboratory at Biology School, Pharmacy Faculty, San Carlos University of Guatemala, Guatemala City, Guatemala
| | - Antonieta Rodas
- The Applied Entomology and Parasitology Laboratory at Biology School, Pharmacy Faculty, San Carlos University of Guatemala, Guatemala City, Guatemala
| | - Vianney Abrego
- Centro de Investigación y desarrollo en salud (CENSALUD-CID), Universidad de El Salvador, San Salvador, El Salvador
| | | | - María Carlota Monroy
- The Applied Entomology and Parasitology Laboratory at Biology School, Pharmacy Faculty, San Carlos University of Guatemala, Guatemala City, Guatemala
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Keller JI, Schmidt JO, Schmoker AM, Ballif BA, Stevens L. Protein mass spectrometry extends temporal blood meal detection over polymerase chain reaction in mouse-fed Chagas disease vectors. Mem Inst Oswaldo Cruz 2018; 113:e180160. [PMID: 30277492 PMCID: PMC6167943 DOI: 10.1590/0074-02760180160] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/03/2018] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Chagas disease is highly prevalent in Latin America, and vector control is the most effective control strategy to date. We have previously shown that liquid chromatography tandem mass spectrometry (LC-MS/MS) is a valuable tool for identifying triatomine vector blood meals. OBJECTIVES The purpose of this study was to determine blood meal detection ability as a function of method [polymerase chain reaction (PCR) vs. LC-MS/MS], time since feeding, and the effect of molting in mouse-fed triatomine insect vectors targeting hemoglobin and albumin proteins with LC-MS/MS and short interspersed nuclear elements (SINE)-based PCR. METHODS We experimentally fed Triatoma protracta on mice and used LC-MS/MS to detect hemoglobin and albumin peptides over time post-feeding and post-molting (≤ 12 weeks). We compared LC-MS/MS results with those of a standard PCR method based on SINEs. FINDINGS Hemoglobin-based LC-MS/MS detected blood meals most robustly at all time points post-feeding. Post-molting, no blood meals were detected with PCR, whereas LC-MS/MS detected mouse hemoglobin and albumin up to 12 weeks. MAIN CONCLUSIONS In our study, the hemoglobin signature in the insect abdomen lasted longer than that of albumin and DNA. LC-MS/MS using hemoglobin shows promise for identifying triatomine blood meals over long temporal scales and even post-molting. Clarifying the frequency of blood-feeding on different hosts can foster our understanding of vector behavior and may help devise sounder disease-control strategies, including Ecohealth (community based ecosystem management) approaches.
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Affiliation(s)
- Judith I Keller
- University of Vermont, Department of Biology, Burlington, VT, United States of America
| | - Justin O Schmidt
- Southwestern Biological Institute, Tucson, AZ, United States of America
| | - Anna M Schmoker
- University of Vermont, Department of Biology, Burlington, VT, United States of America
| | - Bryan A Ballif
- University of Vermont, Department of Biology, Burlington, VT, United States of America
| | - Lori Stevens
- University of Vermont, Department of Biology, Burlington, VT, United States of America
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Piccinali RV, Gaunt MW, Gürtler RE. A Microsatellite-Based Analysis of House Infestation With Triatoma Infestans (Hemiptera: Reduviidae) After Insecticide Spraying in the Argentine Chaco. JOURNAL OF MEDICAL ENTOMOLOGY 2018; 55:609-619. [PMID: 29385501 DOI: 10.1093/jme/tjx256] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Indexed: 06/07/2023]
Abstract
Prevention of vector-borne transmission of Chagas disease mainly relies on residual insecticide spraying. Despite significant success at a regional scale, house infestation with Triatoma infestans (Klug) (Hemiptera: Reduviidae) still persists in the Gran Chaco ecoregion. One key aspect is the identification of the sources of reinfestant triatomines. After detecting fine-scale genetic structure in two rural villages of Pampa del Indio, Argentine Chaco, we tested hypotheses on the putative origins of the triatomines collected at 4, 8, and 12 mo after insecticide house spraying. We genotyped 10 microsatellite loci in 262 baseline and 83 postspraying triatomines from different houses. Genetic variability was similar between baseline and postspraying populations, but 13 low-frequency alleles were not detected at postspraying. FSTs were not significant between insects collected before and after insecticide spraying at the same house in all but one case, and they clustered together in a neighbor-joining tree. A clustering algorithm detected seven genetic groups, four of them mainly composed of baseline and postspraying insects from the same house. Assignment tests suggested multiple putative sources (including the house of collection) for most postspraying insects but excluded a house located more than 9 km from the study area. The origin of three triatomines was attributed to immigration from other unaccounted sources. Our study is compatible with the hypothesis that house reinfestations in the Argentine Chaco are mostly related to residual foci (i.e., survival of insects within the same community), in agreement with field observations, spatial analysis, and morphometric studies previously published.
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Affiliation(s)
- Romina V Piccinali
- Facultad de Ciencias Exactas y Naturales, Departamento de Ecología, Genética y Evolución, Laboratorio de Eco-Epidemiología Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
- Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), CONICET-Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
| | - Michael W Gaunt
- Infectious and Tropical Diseases Department, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Ricardo E Gürtler
- Facultad de Ciencias Exactas y Naturales, Departamento de Ecología, Genética y Evolución, Laboratorio de Eco-Epidemiología Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
- Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), CONICET-Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina
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Keller JI, Ballif BA, St. Clair RM, Vincent JJ, Monroy MC, Stevens L. Chagas disease vector blood meal sources identified by protein mass spectrometry. PLoS One 2017; 12:e0189647. [PMID: 29232402 PMCID: PMC5726658 DOI: 10.1371/journal.pone.0189647] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 11/29/2017] [Indexed: 02/08/2023] Open
Abstract
Chagas disease is a complex vector borne parasitic disease involving blood feeding Triatominae (Hemiptera: Reduviidae) insects, also known as kissing bugs, and the vertebrates they feed on. This disease has tremendous impacts on millions of people and is a global health problem. The etiological agent of Chagas disease, Trypanosoma cruzi (Kinetoplastea: Trypanosomatida: Trypanosomatidae), is deposited on the mammalian host in the insect’s feces during a blood meal, and enters the host’s blood stream through mucous membranes or a break in the skin. Identifying the blood meal sources of triatomine vectors is critical in understanding Chagas disease transmission dynamics, can lead to identification of other vertebrates important in the transmission cycle, and aids management decisions. The latter is particularly important as there is little in the way of effective therapeutics for Chagas disease. Several techniques, mostly DNA-based, are available for blood meal identification. However, further methods are needed, particularly when sample conditions lead to low-quality DNA or to assess the risk of human cross-contamination. We demonstrate a proteomics-based approach, using liquid chromatography tandem mass spectrometry (LC-MS/MS) to identify host-specific hemoglobin peptides for blood meal identification in mouse blood control samples and apply LC-MS/MS for the first time to Triatoma dimidiata insect vectors, tracing blood sources to species. In contrast to most proteins, hemoglobin, stabilized by iron, is incredibly stable even being preserved through geologic time. We compared blood stored with and without an anticoagulant and examined field-collected insect specimens stored in suboptimal conditions such as at room temperature for long periods of time. To our knowledge, this is the first study using LC-MS/MS on field-collected arthropod disease vectors to identify blood meal composition, and where blood meal identification was confirmed with more traditional DNA-based methods. We also demonstrate the potential of synthetic peptide standards to estimate relative amounts of hemoglobin acquired when insects feed on multiple blood sources. These LC-MS/MS methods can contribute to developing Ecohealth control strategies for Chagas disease transmission and can be applied to other arthropod disease vectors.
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Affiliation(s)
- Judith I. Keller
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - Bryan A. Ballif
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
- * E-mail: (LS); (BAB)
| | - Riley M. St. Clair
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - James J. Vincent
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - M. Carlota Monroy
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Facultad de Ciencias Químicas y Farmacia, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala
| | - Lori Stevens
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
- * E-mail: (LS); (BAB)
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Triana DRR, Mertens F, Zúniga CV, Mendoza Y, Nakano EY, Monroy MC. The Role of Gender in Chagas Disease Prevention and Control in Honduras: An Analysis of Communication and Collaboration Networks. ECOHEALTH 2016; 13:535-548. [PMID: 27405994 DOI: 10.1007/s10393-016-1141-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/19/2016] [Accepted: 05/25/2016] [Indexed: 06/06/2023]
Abstract
In Honduras, where Chagas disease is a serious health and environmental concern, prevention measures face the challenge of achieving widespread and long-term sustainable adoption by communities. The article integrates social network analysis and a gender-sensitive approach to understand the role of men and women in the implementation of a community-level intervention, based on the adoption of housing improvements to reduce the presence of the insect vector. A total of 108 people in the community of El Salitre were interviewed. Data were collected on socio-demographic characteristics, participation in project activities, communication and collaboration networks related to Chagas disease prevention, knowledge of Chagas disease, and adoption of housing improvements techniques. Communication mostly occurred between the same gender individuals and was associated with knowledge of Chagas disease. Socioeconomic status, Chagas disease knowledge, and collaboration with men were associated with women adopting housing improvements. For men, however, participation in project activities, formal education, and collaboration with women were associated with adoption. These findings suggest that men and women were driven by distinct concerns, interests, and motivations when adopting new Chagas disease prevention strategies. Participatory community interventions that seek to generate health knowledge and foster collaborations to reduce health risk should address gender differences.
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Affiliation(s)
| | - Frédéric Mertens
- Centro de Desenvolvimento Sustentável, Universidade de Brasília, Asa Norte, Brasília, 70910-900, DF, Brazil.
- Community of Practice in Ecosystem Approaches to Health in Latin America and the Caribbean (CoPEH-LAC), Brasília, Brazil.
| | | | - Yolanda Mendoza
- Ecohealth Field Building Leadership in Prevention and Control of Vector Borne Diseases in Latin America and the Caribbean, Tegucigalpa, Honduras
| | | | - Maria Carlota Monroy
- Laboratorio de entomologia aplicada y Parasitología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala, Guatemala
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De Urioste-Stone SM, Pennington PM, Pellecer E, Aguilar TM, Samayoa G, Perdomo HD, Enríquez H, Juárez JG. Development of a community-based intervention for the control of Chagas disease based on peridomestic animal management: an eco-bio-social perspective. Trans R Soc Trop Med Hyg 2015; 109:159-67. [PMID: 25604767 PMCID: PMC4299527 DOI: 10.1093/trstmh/tru202] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background Integrated vector management strategies depend on local eco-bio-social conditions, community participation, political will and inter-sectorial partnership. Previously identified risk factors for persistent Triatoma dimidiata infestation include the presence of rodents and chickens, tiled roofs, dirt floors, partial wall plastering and dog density. Methods A community-based intervention was developed and implemented based on cyclical stakeholder and situational analyses. Intervention implementation and evaluation combined participatory action research and cluster randomized pre-test post-test experimental designs. The intervention included modified insecticide application, education regarding Chagas disease and risk factors, and participatory rodent control. Results At final evaluation there was no significant difference in post-test triatomine infestation between intervention and control, keeping pre-test rodent and triatomine infestations constant. Knowledge levels regarding Chagas disease and prevention practices including rodent control, chicken management and health service access increased significantly only in intervention communities. The odds of nymph infection and rat infestation were 8.3 and 1.9-fold higher in control compared to intervention communities, respectively. Conclusion Vector control measures without reservoir control are insufficient to reduce transmission risk in areas with persistent triatomine infestation. This integrated vector management program can complement house improvement initiatives by prioritizing households with risk factors such as tiled roofs. Requirement for active participation and multi-sectorial coordination poses implementation challenges.
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Affiliation(s)
| | - Pamela M Pennington
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala 01015, Guatemala
| | - Elizabeth Pellecer
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala 01015, Guatemala
| | - Teresa M Aguilar
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala 01015, Guatemala
| | - Gabriela Samayoa
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala 01015, Guatemala
| | - Hugo D Perdomo
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala 01015, Guatemala
| | - Hugo Enríquez
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala 01015, Guatemala
| | - José G Juárez
- Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala 01015, Guatemala
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Waleckx E, Camara-Mejia J, Ramirez-Sierra MJ, Cruz-Chan V, Rosado-Vallado M, Vazquez-Narvaez S, Najera-Vazquez R, Gourbière S, Dumonteil E. An innovative ecohealth intervention for Chagas disease vector control in Yucatan, Mexico. Trans R Soc Trop Med Hyg 2015; 109:143-9. [PMID: 25604765 PMCID: PMC4299525 DOI: 10.1093/trstmh/tru200] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Background Non-domiciliated (intrusive) triatomine vectors remain a challenge for the sustainability of Chagas disease vector control as these triatomines are able to transiently (re-)infest houses. One of the best-characterized examples is Triatoma dimidiata from the Yucatan peninsula, Mexico, where adult insects seasonally infest houses between March and July. Methods We focused our study on three rural villages in the state of Yucatan, Mexico, in which we performed a situation analysis as a first step before the implementation of an ecohealth (ecosystem approach to health) vector control intervention. Results The identification of the key determinants affecting the transient invasion of human dwellings by T. dimidiata was performed by exploring associations between bug presence and qualitative and quantitative variables describing the ecological, biological and social context of the communities. We then used a participatory action research approach for implementation and evaluation of a control strategy based on window insect screens to reduce house infestation by T. dimidiata. Conclusions This ecohealth approach may represent a valuable alternative to vertically-organized insecticide spraying. Further evaluation may confirm that it is sustainable and provides effective control (in the sense of limiting infestation of human dwellings and vector/human contacts) of intrusive triatomines in the region.
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Affiliation(s)
- Etienne Waleckx
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - Javier Camara-Mejia
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - Maria Jesus Ramirez-Sierra
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - Vladimir Cruz-Chan
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - Miguel Rosado-Vallado
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - Santos Vazquez-Narvaez
- Departamento de Control de Vectores, Servicios de Salud de Yucatán, Mérida, Yucatán, Mexico
| | - Rosario Najera-Vazquez
- Departamento de Control de Vectores, Servicios de Salud de Yucatán, Mérida, Yucatán, Mexico
| | - Sébastien Gourbière
- EA 4218 Institut de Modélisation et d'Analyses en Géo-Environnement et Santé, Université de Perpignan Via Domitia, Perpignan, France
| | - Eric Dumonteil
- Laboratorio de Parasitología, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
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Hashimoto K, Zúniga C, Romero E, Morales Z, Maguire JH. Determinants of Health Service Responsiveness in Community-Based Vector Surveillance for Chagas Disease in Guatemala, El Salvador, and Honduras. PLoS Negl Trop Dis 2015; 9:e0003974. [PMID: 26252767 PMCID: PMC4529194 DOI: 10.1371/journal.pntd.0003974] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Accepted: 07/12/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Central American countries face a major challenge in the control of Triatoma dimidiata, a widespread vector of Chagas disease that cannot be eliminated. The key to maintaining the risk of transmission of Trypanosoma cruzi at lowest levels is to sustain surveillance throughout endemic areas. Guatemala, El Salvador, and Honduras integrated community-based vector surveillance into local health systems. Community participation was effective in detection of the vector, but some health services had difficulty sustaining their response to reports of vectors from the population. To date, no research has investigated how best to maintain and reinforce health service responsiveness, especially in resource-limited settings. METHODOLOGY/PRINCIPAL FINDINGS We reviewed surveillance and response records of 12 health centers in Guatemala, El Salvador, and Honduras from 2008 to 2012 and analyzed the data in relation to the volume of reports of vector infestation, local geography, demography, human resources, managerial approach, and results of interviews with health workers. Health service responsiveness was defined as the percentage of households that reported vector infestation for which the local health service provided indoor residual spraying of insecticide or educational advice. Eight potential determinants of responsiveness were evaluated by linear and mixed-effects multi-linear regression. Health service responsiveness (overall 77.4%) was significantly associated with quarterly monitoring by departmental health offices. Other potential determinants of responsiveness were not found to be significant, partly because of short- and long-term strategies, such as temporary adjustments in manpower and redistribution of tasks among local participants in the effort. CONCLUSIONS/SIGNIFICANCE Consistent monitoring within the local health system contributes to sustainability of health service responsiveness in community-based vector surveillance of Chagas disease. Even with limited resources, countries can improve health service responsiveness with thoughtful strategies and management practices in the local health systems.
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Affiliation(s)
- Ken Hashimoto
- Chagas Disease Control Project, Japan International Cooperation Agency, Tegucigalpa, Honduras
| | - Concepción Zúniga
- National Chagas Disease Control Program, Directorate of Health Promotion, Ministry of Health, Tegucigalpa, Honduras
| | - Eduardo Romero
- National Vector-Borne Diseases Control Unit, Directorate of Environmental Health, Ministry of Health, San Salvador, El Salvador
| | - Zoraida Morales
- National Vector-Borne Disease Control Program, Department of Regulation of Healthcare Programs, Ministry of Health, Guatemala City, Guatemala
| | - James H. Maguire
- Brigham and Women´s Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
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Bustamante Zamora DM, Hernández MM, Torres N, Zúniga C, Sosa W, de Abrego V, Monroy Escobar MC. Information to act: household characteristics are predictors of domestic infestation with the Chagas vector Triatoma dimidiata in Central America. Am J Trop Med Hyg 2015; 93:97-107. [PMID: 25870430 DOI: 10.4269/ajtmh.14-0596] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 03/05/2015] [Indexed: 11/07/2022] Open
Abstract
The interruption of vectorial transmission of Chagas disease by Triatoma dimidiata in central America is a public health challenge that cannot be resolved by insecticide application alone. In this study, we collected information on previously known household risk factors for infestation in 11 villages and more than 2,000 houses in Guatemala, Honduras, and El Salvador, and we constructed multivariate models and used multimodel inference to evaluate their importance as predictors of infestation in the region. The models had moderate ability to predict infested houses (sensitivity, 0.32-0.54) and excellent ability to predict noninfested houses (specificity higher than 0.90). Predictive ability was improved by including random village effects and presence of signs of infestation (insect feces, eggs, and exuviae) as fixed effects. Multimodel inference results varied depending on factors included, but house wall materials (adobe, bajareque, and palopique) and signs of infestation were among the most important predictive factors. Reduced models were not supported suggesting that all factors contributed to predictions. Previous knowledge and information from this study show that we have evidence to prioritize rural households for improvement to prevent house infestation with Triatoma dimidiata in Central America. House improvement will most likely have other health co-benefits.
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Affiliation(s)
- Dulce María Bustamante Zamora
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala; Administración Académica, Universidad de San Salvador, San Salvador, El Salvador; Centro de Investigación y Desarrollo en Salud, Universidad de San Salvador, San Salvador, El Salvador; Escuela de Microbiología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras; Programa Nacional de Prevención y Control de la Enfermedad de Chagas, Secretaría de Salud, Tegucigalpa, Honduras
| | - Marianela Menes Hernández
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala; Administración Académica, Universidad de San Salvador, San Salvador, El Salvador; Centro de Investigación y Desarrollo en Salud, Universidad de San Salvador, San Salvador, El Salvador; Escuela de Microbiología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras; Programa Nacional de Prevención y Control de la Enfermedad de Chagas, Secretaría de Salud, Tegucigalpa, Honduras
| | - Nuria Torres
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala; Administración Académica, Universidad de San Salvador, San Salvador, El Salvador; Centro de Investigación y Desarrollo en Salud, Universidad de San Salvador, San Salvador, El Salvador; Escuela de Microbiología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras; Programa Nacional de Prevención y Control de la Enfermedad de Chagas, Secretaría de Salud, Tegucigalpa, Honduras
| | - Concepción Zúniga
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala; Administración Académica, Universidad de San Salvador, San Salvador, El Salvador; Centro de Investigación y Desarrollo en Salud, Universidad de San Salvador, San Salvador, El Salvador; Escuela de Microbiología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras; Programa Nacional de Prevención y Control de la Enfermedad de Chagas, Secretaría de Salud, Tegucigalpa, Honduras
| | - Wilfredo Sosa
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala; Administración Académica, Universidad de San Salvador, San Salvador, El Salvador; Centro de Investigación y Desarrollo en Salud, Universidad de San Salvador, San Salvador, El Salvador; Escuela de Microbiología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras; Programa Nacional de Prevención y Control de la Enfermedad de Chagas, Secretaría de Salud, Tegucigalpa, Honduras
| | - Vianney de Abrego
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala; Administración Académica, Universidad de San Salvador, San Salvador, El Salvador; Centro de Investigación y Desarrollo en Salud, Universidad de San Salvador, San Salvador, El Salvador; Escuela de Microbiología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras; Programa Nacional de Prevención y Control de la Enfermedad de Chagas, Secretaría de Salud, Tegucigalpa, Honduras
| | - María Carlota Monroy Escobar
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Universidad de San Carlos, Ciudad de Guatemala, Guatemala; Administración Académica, Universidad de San Salvador, San Salvador, El Salvador; Centro de Investigación y Desarrollo en Salud, Universidad de San Salvador, San Salvador, El Salvador; Escuela de Microbiología, Universidad Nacional Autónoma de Honduras, Tegucigalpa, Honduras; Programa Nacional de Prevención y Control de la Enfermedad de Chagas, Secretaría de Salud, Tegucigalpa, Honduras
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Rossi JCN, Duarte EC, Gurgel-Gonçalves R. Factors associated with the occurrence of Triatoma sordida (Hemiptera: Reduviidae) in rural localities of Central-West Brazil. Mem Inst Oswaldo Cruz 2015; 110:192-200. [PMID: 25946242 PMCID: PMC4489449 DOI: 10.1590/0074-02760140395] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 12/19/2014] [Indexed: 11/21/2022] Open
Abstract
This study estimates the factors of artificial environments (houses and peridomestic areas) associated with Triatoma sordida occurrence. Manual searches for triatomines were performed in 136 domiciliary units (DUs) in two rural localities of Central-West Brazil. For each DU, 32 structural, 23 biotic and 28 management variables were obtained. Multiple logistic regression analysis was performed in order to identify statistically significant variables associated with occurrence of T. sordida in the study areas. A total of 1,057 specimens (99% in peridomiciles, mainly chicken coops) of T. sordida were collected from 63 DUs (infestation: 47%; density: ~8 specimens/DU; crowding: ~17 specimens/infested DU; colonisation: 81%). Only six (0.6%) out of 945 specimens examined were infected with Trypanosoma cruzi. The final adjusted logistic regression model indicated that the probability of T. sordida occurrence was higher in DU with wooden chicken coops, presence of > 30 animals in wooden corrals, presence of wood piles and presence of food storeroom. The results show the persistence of T. sordida in peridomestic habitats in rural localities of Central-West Brazil. However, the observed low intradomestic colonisation and minimal triatomine infection rates indicate that T. sordida has low potential to sustain high rates of T. cruzi transmission to residents of these localities.
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Nouvellet P, Cucunubá ZM, Gourbière S. Ecology, evolution and control of Chagas disease: a century of neglected modelling and a promising future. ADVANCES IN PARASITOLOGY 2015; 87:135-91. [PMID: 25765195 DOI: 10.1016/bs.apar.2014.12.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
More than 100 years after its formal description, Chagas disease remains a major public health concern in Latin America with a yearly burden of 430,000 Disability-Adjusted Life Years (DALYs). The aetiological agent, a protozoan named Trypanosoma cruzi, is mainly transmitted to mammalian hosts by triatomine vectors. Multiple species of mammals and triatomines can harbour and transmit the parasite, and the feeding range of triatomine species typically includes many noncompetent hosts. Furthermore, the transmission of the pathogen can occur via several routes including the typical vector's faeces, but also oral, congenital and blood transfusion routes. These ecological and epidemiological complexities of the disease have hindered many control initiatives. In such a context, mathematical models provide invaluable tools to explore and understand the dynamics of T. cruzi transmission, and to design, optimize and monitor the efficacy of control interventions. We intend here to provide the first review of the mathematical models of Chagas disease, focussing on how they have contributed to our understanding of (1) the population dynamics and control of triatomine vectors, and (2) the epidemiology of T. cruzi infections. We also aim at suggesting promising lines of modelling that could further improve our understanding of the ecology, evolution, and control of the disease.
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Affiliation(s)
- Pierre Nouvellet
- Medical Research Council Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Zulma M Cucunubá
- Grupo de Parasitología, Instituto Nacional de Salud, Colombia; Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Sébastien Gourbière
- Institut de Modélisation et d'Analyse en Géo-Environnements et Santé (IMAGES), Université de Perpignan Via Domitia, Perpignan, France
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Ecological, social and biological risk factors for continued Trypanosoma cruzi transmission by Triatoma dimidiata in Guatemala. PLoS One 2014; 9:e104599. [PMID: 25170955 PMCID: PMC4149347 DOI: 10.1371/journal.pone.0104599] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 07/15/2014] [Indexed: 11/24/2022] Open
Abstract
Background Chagas disease transmission by Triatoma dimidiata persists in Guatemala and elsewhere in Central America under undefined ecological, biological and social (eco-bio-social) conditions. Methodology Eco-bio-social risk factors associated with persistent domiciliary infestation were identified by a cross-sectional survey and qualitative participatory methods. Quantitative and qualitative data were generated regarding Trypanosoma cruzi reservoirs and triatomine hosts. Blood meal analysis and infection of insects, dogs and rodents were determined. Based on these data, multimodel inference was used to identify risk factors for domestic infestation with the greatest relative importance (>0.75). Principal Findings Blood meal analysis showed that 64% of 36 bugs fed on chickens, 50% on humans, 17% on dogs; 24% of 34 bugs fed on Rattus rattus and 21% on Mus musculus. Seroprevalence among 80 dogs was 37%. Eight (17%) of 46 M. musculus and three (43%) of seven R. rattus from households with infected triatomines were infected with T. cruzi Distinct Typing Unit I. Results from interviews and participatory meetings indicated that vector control personnel and some householders perceived chickens roosting and laying eggs in the house as bug infestation risk factors. House construction practices were seen as a risk factor for bug and rodent infestation, with rodents being perceived as a pest by study participants. Multimodel inference showed that house infestation risk factors of high relative importance are dog density, mouse presence, interior wall plaster condition, dirt floor, tile roofing and coffee tree presence. Conclusions/Significance Persistent house infestation is closely related to eco-bio-social factors that maintain productive T. dimidiata habitats associated with dogs, chickens and rodents. Triatomine, dog and rodent infections indicate active T. cruzi transmission. Integrated vector control methods should include actions that consider the role of peridomestic animals in transmission and community memberś level of knowledge, attitudes and practices associated with the disease and transmission process.
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Grijalva MJ, Terán D, Dangles O. Dynamics of sylvatic Chagas disease vectors in coastal Ecuador is driven by changes in land cover. PLoS Negl Trop Dis 2014; 8:e2960. [PMID: 24968118 PMCID: PMC4072561 DOI: 10.1371/journal.pntd.0002960] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 05/08/2014] [Indexed: 11/18/2022] Open
Abstract
Background Chagas disease is a serious public health problem in Latin America where about ten million individuals show Trypanosoma cruzi infection. Despite significant success in controlling domiciliated triatomines, sylvatic populations frequently infest houses after insecticide treatment which hampers long term control prospects in vast geographical areas where vectorial transmission is endemic. As a key issue, the spatio-temporal dynamics of sylvatic populations is likely influenced by landscape yet evidence showing this effect is rare. The aim of this work is to examine the role of land cover changes in sylvatic triatomine ecology, based on an exhaustive field survey of pathogens, vectors, hosts, and microhabitat characteristics' dynamics. Methodology and Principal Findings The study was performed in agricultural landscapes of coastal Ecuador as a study model. Over one year, a spatially-randomized sampling design (490 collection points) allowed quantifying triatomine densities in natural, cultivated and domestic habitats. We also assessed infection of the bugs with trypanosomes, documented their microhabitats and potential hosts, and recorded changes in landscape characteristics. In total we collected 886 individuals, mainly represented by nymphal stages of one triatomine species Rhodnius ecuadoriensis. As main results, we found that 1) sylvatic triatomines had very high T. cruzi infection rates (71%) and 2) densities of T. cruzi-infected sylvatic triatomines varied predictably over time due to changes in land cover and occurrence of associated rodent hosts. Conclusion We propose a framework for identifying the factors affecting the yearly distribution of sylvatic T. cruzi vectors. Beyond providing key basic information for the control of human habitat colonization by sylvatic vector populations, our framework highlights the importance of both environmental and sociological factors in shaping the spatio-temporal population dynamics of triatomines. A better understanding of the dynamics of such socio-ecological systems is a crucial, yet poorly considered, issue for the long-term control of Chagas disease. Globally, more than 10 million people are infected with Trypanosoma cruzi. The emergence and perpetuation of Chagas disease in some endemic countries, such as Ecuador, depends largely on sylvatic populations of T. cruzi-infected vectors that frequently infest houses after insecticide treatment thereby hampering long-term control prospects in vast geographical areas. Our study describes, for the first time in an agricultural landscape, how the temporal dynamics of sylvatic vector, host, and pathogen populations interact spatially in a farming community of coastal Ecuador. In particular, we found that land cover changes due to both farming activities and vegetation phenology affect rodent host distribution and consequently the relative abundance of vectors involved in the transmission cycle of T. cruzi.
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Affiliation(s)
- Mario J. Grijalva
- Center for Infectious Disease Research, School of Biological Sciences, Pontifical Catholic University of Ecuador, Quito, Ecuador
- Tropical Disease Institute, Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
- * E-mail: ,
| | - David Terán
- Center for Infectious Disease Research, School of Biological Sciences, Pontifical Catholic University of Ecuador, Quito, Ecuador
| | - Olivier Dangles
- Laboratory of Entomology, School of Biological Sciences, Pontifical Catholic University of Ecuador, Quito, Ecuador
- Institut de Recherche pour le Développement (IRD), UR 072, Laboratoire Evolution, Génomes et Spéciation, UPR 9034, Centre National de la Recherche Scientifique (CNRS), Gif sur Yvette, France et Université Paris-Sud 11, Orsay, France
- Instituto de Ecología, Universidad Mayor San Andrés, Cotacota, La Paz, Bolivia
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Hurtado LA, Cáceres L, Chaves LF, Calzada JE. When climate change couples social neglect: malaria dynamics in Panamá. Emerg Microbes Infect 2014; 3:e27. [PMID: 26038518 PMCID: PMC4008768 DOI: 10.1038/emi.2014.27] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 02/28/2014] [Accepted: 03/03/2014] [Indexed: 11/09/2022]
Abstract
A major challenge of infectious disease elimination is the need to interrupt pathogen transmission across all vulnerable populations. Ethnic minorities are among the key vulnerable groups deserving special attention in disease elimination initiatives, especially because their lifestyle might be intrinsically linked to locations with high transmission risk. There has been a renewed interest in malaria elimination, which has ignited a quest to understand factors necessary for sustainable malaria elimination, highlighting the need for diverse approaches to address epidemiological heterogeneity across malaria transmission settings. An analysis of malaria incidence among the Guna Amerindians of Panamá over the last 34 years showed that this ethnic minority was highly vulnerable to changes that were assumed to not impact malaria transmission. Epidemic outbreaks were linked with El Niño Southern Oscillations and were sensitive to political instability and policy changes that did not ensure adequate attention to the malaria control needs of the Gunas. Our results illustrate how the neglect of minorities poses a threat to the sustainable control and eventual elimination of malaria in Central America and other areas where ethnic minorities do not share the benefits of malaria control strategies intended for dominant ethnic groups.
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Affiliation(s)
- Lisbeth Amarilis Hurtado
- Departamento de Parasitología, Instituto Conmemorativo Gorgas de Estudios de la Salud (ICGES), Apartado Postal No. 0816-02593 , Ciudad de Panamá, República de Panamá
| | - Lorenzo Cáceres
- Departamento de Entomología Médica, Instituto Conmemorativo Gorgas de Estudios de la Salud (ICGES), Apartado Postal No. 0816-02593 , Ciudad de Panamá, República de Panamá
| | - Luis Fernando Chaves
- Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto , Nagasaki 852-8523, Japan ; Programa de Investigación en Enfermedades Tropicales (PIET), Escuela de Medicina Veterinaria, Universidad Nacional, Apartado Postal No. 304-3000 , Heredia, Costa Rica
| | - José E Calzada
- Departamento de Parasitología, Instituto Conmemorativo Gorgas de Estudios de la Salud (ICGES), Apartado Postal No. 0816-02593 , Ciudad de Panamá, República de Panamá
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Pellecer MJ, Dorn PL, Bustamante DM, Rodas A, Monroy MC. Vector blood meals are an early indicator of the effectiveness of the Ecohealth approach in halting Chagas transmission in Guatemala. Am J Trop Med Hyg 2013; 88:638-44. [PMID: 23382165 PMCID: PMC3617846 DOI: 10.4269/ajtmh.12-0458] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Accepted: 12/28/2012] [Indexed: 11/07/2022] Open
Abstract
A novel method using vector blood meal sources to assess the impact of control efforts on the risk of transmission of Chagas disease was tested in the village of El Tule, Jutiapa, Guatemala. Control used Ecohealth interventions, where villagers ameliorated the factors identified as most important for transmission. First, after an initial insecticide application, house walls were plastered. Later, bedroom floors were improved and domestic animals were moved outdoors. Only vector blood meal sources revealed the success of the first interventions: human blood meals declined from 38% to 3% after insecticide application and wall plastering. Following all interventions both vector blood meal sources and entomological indices revealed the reduction in transmission risk. These results indicate that vector blood meals may reveal effects of control efforts early on, effects that may not be apparent using traditional entomological indices, and provide further support for the Ecohealth approach to Chagas control in Guatemala.
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Affiliation(s)
- Mariele J Pellecer
- Universidad de San Carlos, Guatemala City, Guatemala; Loyola University New Orleans, New Orleans, LA, USA.
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