Analysis of children's perception of triatomine vectors of chagas disease through drawings: opportunities for targeted health education

Temporal variation of Triatoma dimidiata abundance and infection with Trypanosoma cruzi in domestic and sylvatic habitats of rural Yucatan, Mexico

In the Yucatan Peninsula, Mexico, Triatoma dimidiata is the main vector of Chagas disease. This is a native species in the region that principally inhabits sylvatic habitats. Nevertheless, it shows a tolerant behavior to anthropogenic disturbance, with adult bugs frequently infesting human dwellings, principally during the warm and dry season. Yet, whether the temporal variation of abundance is independent of the habitat and how this is related to the infection rate with Trypanosoma cruzi in Yucatan is still poorly understood. The objective of this study was to simultaneously analyze the temporal variations of T. dimidiata abundance and infection with T. cruzi in domestic and sylvatic habitats from two localities of rural Yucatan (Sudzal, 20°52'19″N, 88°59'20″W and Teya, 21°02'55″N, 89°04'25″W) to help for the further improvement of locally adapted strategies aimed at controlling T. cruzi vector transmission. Using community participation and a combination of different trapping techniques, we collected T. dimidiata bugs during 29 consecutive months within domestic and sylvatic habitats. We then assessed by PCR the infection of the bugs with T. cruzi. Generalized linear models were used to evaluate the effect of climatic variables on the abundance of T. dimidiata and the effect of bug sex, season and habitat on the prevalence of infection with T. cruzi. Overall, 3640 specimens of T. dimidiata were collected. We clearly observed peaks of maximum abundance in both habitats during the warm and dry season and found a negative association of bug abundance with relative humidity. The overall prevalence of infection of the bugs with T. cruzi was 15.2 %. Additionally, bugs collected in domestic habitats displayed a significantly higher prevalence of infection than sylvatic bugs (19.6% vs. 6.1 %, respectively), suggesting an increased risk of T. cruzi transmission related with anthropogenic disturbance. Our study is the first to describe the annual pattern of abundance of T. dimidiata in sylvatic habitats of rural Yucatan and constitutes a contribution to the knowledge of T. dimidiata ecology and of T. cruzi transmission cycle dynamics in the region. In Yucatan, where the use of mosquito nets has shown to be effective to limit human dwelling infestation by T. dimidiata, reinforcing the awareness of local residents about the increased risk of T. cruzi transmission during the warm and dry season when realizing activities in the sylvatic ambient should be, among others, also considered to improve control strategies and limit the risk of vector transmission.

Perception of risk among children: Exploring the risk of TB-rickettsial disease based on the children's drawing pictures in a Mayan community of Yucatan

Background

It is important to work on designs of health promotion strategies that involve educational interventions about the risk factors associated to TB-rickettsiosis (Tick-Borne rickettsiosis). Children's drawings provide a window into their thoughts and feelings. The aim was to analyze children's risk perceptions regarding by the presence of ticks in a rural community in southeast Mexico.

Methods

The main framework used was a social cognitive perspective under the Health Belief Model. Study was carried out in rural elementary schools and included a drawing contest. A total of 224 children (8-12 years old) participated. Drawings were coded and classified; descriptive trend analysis was performed using counts and percentages. The qualitative data was analyzed by researcher experts in TB- rickettsiosis and using Atlas ti V.8.

Results

Results are presented in seven categories that consider environmental elements, actors, and cognitive aspects. The environmental context, 99.1% of the drawings represent sites outside the home (92% include vegetation with the presence of ticks in their immediate external environment). In the actors' category, 69.6% included people carrying out activities (prevention and risk). As for the cognitive aspects, 70% included domestic pets and 13.4% farmyards animals.

Conclusion

The children expressed their ideas about risk factors and preventive measures against TB-rickettsiosis with a self-care approach. They acquired knowledge about preventive strategies and clinical symptoms. It is necessary to evaluate what happens after an intervention and how they implement in their lives what they have learned.

Communication in Neglected Tropical Diseases' elimination: A scoping review and call for action

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.

Eco-epidemiology of vectorial Trypanosoma cruzi transmission in a region of northeast Brazil

Chagas disease (CD) is a parasitic zoonosis endemic in Brazil. Despite virtual control of Triatoma infestans, the main domesticated vector of Trypanosoma cruzi, vectorial transmission by other triatomine species persists in some rural communities. This study aims to characterize triatomines role in transmitting T. cruzi to dogs and humans in the district of Santo Inácio, located in the northwest region of the state of Bahia, Brazil. It also describes environmental factors in housings associated with insect occurrence and assesses the perception, knowledge, and preventive practices adopted by the population regarding CD. Blood samples of humans and dogs, and biological samples of triatomines, were collected between November 2018 and February 2019 and subjected to the detection of T. cruzi by serological and molecular biology tests. Also, we applied a questionnaire to research the perception, knowledge, and local practices of people related to CD. The capture of triatomines in households was associated with exploratory variables of the questionnaires using multivariate logistic regression (p < 0.05). The 155 triatomines captured in the wild and domestic environment were of the species Triatoma sherlocki (n = 151), Panstrongylus sherlocki (n = 1) and Triatoma sordida (n = 3), and had a natural infection rate for T. cruzi by PCR of 18.5%, 100% and 0%, respectively. District residents (n = 126) were seronegative for T. cruzi, while 17.5% (7/40) of the dogs were seropositive. The fact that residents are aware that triatomines can "cause" CD was configured as a protection factor for residents according to the fitted logistic regression model (p = 0.04). However, respondents have limited perception and knowledge about the CD, prevention and control practices for triatomines in a household. The results suggest the existence of a domestic cycle of transmission of T. cruzi between triatomines and dogs, configuring a latent risk of infection to the human population of Santo Inácio. Studies that clarify the potential for the establishing of intrusive triatomines in households, surveillance actions for triatomines, and health education in rural communities are indispensable to prevent the reemergence of CD in vulnerable regions of Brazil and other American countries with similar epidemiological characteristics.

Chagas disease in the context of the 2030 agenda: global warming and vectors

The 2030 Agenda for Sustainable Development is a plan of action for people, planet and prosperity. Thousands of years and centuries of colonisation have passed the precarious housing conditions, food insecurity, lack of sanitation, the limitation of surveillance, health care programs and climate change. Chagas disease continues to be a public health problem. The control programs have been successful in many countries in reducing transmission by T. cruzi; but the results have been variable. WHO makes recommendations for prevention and control with the aim of eliminating Chagas disease as a public health problem. Climate change, deforestation, migration, urbanisation, sylvatic vectors and oral transmission require integrating the economic, social, and environmental dimensions of sustainable development, as well as the links within and between objectives and sectors. While the environment scenarios change around the world, native vector species pose a significant public health threat. The man-made atmosphere change is related to the increase of triatomines’ dispersal range, or an increase of the mobility of the vectors from their sylvatic environment to man-made constructions, or humans getting into sylvatic scenarios, leading to an increase of Chagas disease infection. Innovations with the communities and collaborations among municipalities, International cooperation agencies, local governmental agencies, academic partners, developmental agencies, or environmental institutions may present promising solutions, but sustained partnerships, long-term commitment, and strong regional leadership are required. A new world has just opened up for the renewal of surveillance practices, but the lessons learned in the past should be the basis for solutions in the future.

Shelter dogs as indicators for Trypanosoma cruzi infection in an urban area of Aracaju, Brazil

Shelters are places that receive certain species of domestic animals, mostly dogs and cats, that are normally abandoned. These animals are easy to handle because they are crowded and have limited movement. Dogs, due to the close relationship with humans, are considered the main domestic reservoirs in the peridomiciliary cycle of American trypanosomiasis infection in humans. Therefore, in several countries studies are carried out to assess the occurrence of infection in these animals. This work evaluated the occurrence of Trypanosoma cruzi in dogs from shelters in the city of Aracaju, Sergipe. This was an observational and cross-sectional study to detect the occurrence of T. cruzi in blood samples from shelter dogs using polymerase chain reaction (PCR) with the TcZ1/TcZ2 primers. A total of 168 blood samples from dogs (104 females and 64 males) were collected and subjected to DNA and PCR extraction, and seventeen (10.1%) samples showed amplification of the product of the expected size. The TcZ1/TcZ2 primer pair used is considered specific for T. cruzi, and it is capable of amplifying all strains without amplifying other Trypanosoma species. The shelters evaluated had different physical infrastructure; animals positive for T. cruzi were found in all of them, as confirmed by sequencing. It is concluded that shelter dogs, as well as other domestic animals, can function as indicators of the occurrence of T. cruzi in Aracaju-SE, providing relevant epidemiological information for health surveillance and monitoring of Trypanosomatid infections.

Knowledge, behaviour and attitudes towards Chagas disease among the Bolivian migrant population living in Japan: a cross-sectional study

OBJECTIVES

This study aimed to investigate the knowledge, behaviour and attitudes towards Chagas disease (CD) among Latin American migrants in Japan and to evaluate the effectiveness of an educational activity (EA) in increasing knowledge of CD.

DESIGN

A cross-sectional, mixed-methods study employing a preknowledge and postknowledge test and focus group discussion, conducted from March 2018 to June 2018.

PARTICIPANTS

Seventy-two participants were included, all born in Bolivia and residents in four Japanese cities. Fifty-nine of them participated in the EA.

INTERVENTIONS

The EA comprised showing three videos about CD and a group discussion covering different dimensions of CD and was evaluated with questionnaires to analyse the knowledge of the participants before and after.

RESULTS

Seventy-two participants were enrolled, predominantly from highly endemic CD areas of Bolivia. Though most participants were familiar with vector-borne transmission, epidemiology and symptomatology of CD, the baseline knowledge of CD was low. Less than 10% of them had been tested prior for CD. The dominant factors associated with better knowledge were living in Japan for more than 10 years (OR=8.42, 95% CI 1.56 to 48.62) and previously testing for CD (OR=11.32; 95% CI 1.52 to 105.9). The EA significantly improved the CD knowledge of the participants (p value <0.0001; 95% CI 2.32 to 3.84). The participants associated the term 'Chagas' mostly with fear and concern. The level of stigmatisation was low, in contrast to the results of other studies. The barriers encountered in care-seeking behaviour were language, the migration process and difficulties to access the healthcare system.

CONCLUSION

EA with an integrative approach is useful to increase the knowledge of CD within the Bolivian migrant population living in Japan. The activity brings the possibility to explore not only the level of knowledge but also to reveal experiences and to understand the needs of the people at risk. Considering them as actors towards healthcare solutions could lead to better outcomes for the success of future policies and interventions aimed to decrease the global burden.

What are we talking about when we talk about education and Chagas? A systematic review of the issue

More than 110 years has passed since the first publications on Chagas disease, and it still urges the necessity of understanding it as a complex socioenvironmental issue in which components of diverse nature converge and interact beyond the biomedical and epidemiological aspects. The current scenarios of the issue, both rural and Latin American as urban and global, demand that the education on Chagas disease include all possible contexts: where there are insect vectors and where there are not; inside and outside Latin America; in rural, periurban, and urban areas; in formal and non-formal educational environments. We consider essential the requirement of both an integral approach that overcomes the biomedical aspect to include the multidimensionality of the issue and a dialogical educational perspective that allows individuals and communities to analyze, decide, and lead contextualized prevention and promotion actions regarding their health. In this study, we surveyed, described, and critically analyzed studies approaching the link education-Chagas disease in scientific publications from the last 15 years. We aimed at contributing methodological-theoretical elements to (re)think the development of educational research and experiences that truly help facing this issue. From the electronic search of scientific literature in 6 databases, we found 426 articles, out of which we selected 25. We incorporated 10 articles from other sources to this initial corpus and performed both qualitative and quantitative analyses over the total number [35] to characterize the studied works in general, focusing on the conceptions on the Chagas disease issue and the underlying health education approaches.

Cultural perception of triatomine bugs and Chagas disease in Bolivia: a cross-sectional field study

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.

Contributions of citizen scientists to arthropod vector data in the age of digital epidemiology

Citizen-collected arthropod vectors are useful for epidemiological studies of vector-borne disease, especially since the vectors encountered by the public are the subset of vectors in nature that have a disproportionate impact on health. Programs integrating educational efforts with collecting efforts may be particularly effective for public health initiatives, resulting in an empowered public with knowledge of vector-borne disease prevention. Citizen science programs have been successfully implemented for the collection of unprecedented sample sets of mosquitos, ticks, and triatomines. Cyber infrastructure employed in digital epidemiology-including websites, email, mobile phone apps, and social media platforms-has facilitated vector citizen science initiatives to assess disease risk over vast spatial and temporal scales, advancing research to mitigate vector-borne disease risk.

Non-randomized controlled trial of the long-term efficacy of an Ecohealth intervention against Chagas disease in Yucatan, Mexico

Non-domiciliated intrusive triatomine vectors are responsible for a low but significant transmission of Trypanosoma cruzi to humans. Their control is a challenge as insecticide spraying is of limited usefulness, and alternative strategies need to be developed for a sustainable control. We performed a non-randomized controlled trial of an Ecohealth intervention based on window insect screens and community participation to reduce house infestation by Triatoma dimidiata in two rural villages in Yucatan, Mexico. Efficacy of the intervention was measured over a three years follow-up period and entomological indicators showed that the proportion of triatomines found inside houses was significantly reduced in houses with insect screens, which effectively kept more bugs on the outside of houses. Using a previously developed model linking entomological data to the prevalence of infection in human, we predicted that the intervention would lead to a 32% reduction in yearly incidence and in the prevalence of T. cruzi infection. The cost for the coverage of all the windows of a house was of comparable magnitude to what families currently spend on various domestic insecticide, and most screens were still in good conditions after three years. In conclusion, the Ecohealth approach proposed here is effective for the long-term and sustainable control of intrusive T. dimidiata vectors in the Yucatan peninsula, Mexico. This strategy may also be easily adapted to other intrusive triatomine species as well as other regions/countries with comparable eco-epidemiological settings, and would be an excellent component of a larger integrated program for the control of a variety of other vector-borne diseases, bringing additional benefits to the communities. Our results should encourage a further scaling-up of our implementation strategy in additional villages in the region.

Prevention of intestinal parasites in a tri-border area of Latin America: Children perceptions and an integral health education strategy

To investigate knowledge of school-aged children and their perception on intestinal parasites, and to assess knowledge reconstruction on prevention practices after specific training in the subject. We performed an activity package that included the analysis of children's drawings of intestinal parasites, and information and communication technologies (ITCs) to transfer knowledge about these pathogens and prevention measures. Retrieval learning activities were performed to fixation of general and specific prevention and control measures.Overall, we found that there is a knowledge gap in many aspects of parasite biology and ecology, and therefore on the risk of infection and acquisition mechanisms. After ITCs, the children improved their knowledge over non-trained children.The approaches used to transfer knowledge and for learning, fixation were valuable tools for incorporating changes in misconceptions and in the deep-rooted habits that favour entero-parasitic diseases. This has important implications for the specific design of future education materials and campaigns. Understanding of perceptions helps to provide justifications and knowledge to achieve changes in unhealthy habits, and it constitutes the basis for the transformation of many risky practices.

An innovative ecohealth intervention for Chagas disease vector control in Yucatan, Mexico

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.