Optimization of Control Strategies for Non-Domiciliated Triatoma dimidiata, Chagas Disease Vector in the Yucatán Peninsula, Mexico
Open Access
- 14 April 2009
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLoS Neglected Tropical Diseases
- Vol. 3 (4), e416
- https://doi.org/10.1371/journal.pntd.0000416
Abstract
Chagas disease is the most important vector-borne disease in Latin America. Regional initiatives based on residual insecticide spraying have successfully controlled domiciliated vectors in many regions. Non-domiciliated vectors remain responsible for a significant transmission risk, and their control is now a key challenge for disease control. A mathematical model was developed to predict the temporal variations in abundance of non-domiciliated vectors inside houses. Demographic parameters were estimated by fitting the model to two years of field data from the Yucatan peninsula, Mexico. The predictive value of the model was tested on an independent data set before simulations examined the efficacy of control strategies based on residual insecticide spraying, insect screens, and bednets. The model accurately fitted and predicted field data in the absence and presence of insecticide spraying. Pyrethroid spraying was found effective when 50 mg/m2 were applied yearly within a two-month period matching the immigration season. The >80% reduction in bug abundance was not improved by larger doses or more frequent interventions, and it decreased drastically for different timing and lower frequencies of intervention. Alternatively, the use of insect screens consistently reduced bug abundance proportionally to the reduction of the vector immigration rate. Control of non-domiciliated vectors can hardly be achieved by insecticide spraying, because it would require yearly application and an accurate understanding of the temporal pattern of immigration. Insect screens appear to offer an effective and sustainable alternative, which may be part of multi-disease interventions for the integrated control of neglected vector-borne diseases. Chagas disease is the most important vector-borne disease in Latin America. Residual insecticide spraying has been used successfully for the elimination of domestic vectors in many regions. However, some vectors of non-domestic origin are able to invade houses, and they are now a key challenge for further disease control. We developed a mathematical model to predict the temporal variations in abundance of non-domiciliated vectors inside houses, based on triatomine demographic parameters. The reliability of the predictions was demonstrated by comparing these with different sets of insect collection data from the Yucatan peninsula, Mexico. We then simulated vector control strategies based on insecticide spraying, insect, screens and bednets to evaluate their efficacy at reducing triatomine abundance in the houses. An optimum reduction in bug abundance by at least 80% could be obtained by insecticide application only when doses of at least 50 mg/m2 were applied every year within a two-month period matching the house invasion season by bugs. Alternatively, the use of insect screens consistently reduced bug abundance in the houses and offers a sustainable alternative. Such screens may be part of novel interventions for the integrated control of various vector-borne diseases.Keywords
This publication has 49 references indexed in Scilit:
- Variations in Sex Ratio, Feeding, and Fecundity ofTriatoma dimidiata(Hemiptera: Reduviidae) Among Habitats in the Yucatan Peninsula, MexicoVector-Borne and Zoonotic Diseases, 2009
- Usefulness of Community Participation for the Fine Temporal Monitoring of House Infestation by Non-Domiciliated TriatominesJournal of Parasitology, 2009
- Two Distinct Triatoma dimidiata (Latreille, 1811) Taxa Are Found in Sympatry in Guatemala and MexicoPLoS Neglected Tropical Diseases, 2009
- A cellular automata model for Chagas diseaseApplied Mathematical Modelling, 2009
- Dynamics and Distribution of House Infestation byTriatoma dimidiatain Central and Southern BelizeVector-Borne and Zoonotic Diseases, 2009
- Phylogeography and Genetic Variation of Triatoma dimidiata, the Main Chagas Disease Vector in Central America, and Its Position within the Genus TriatomaPLoS Neglected Tropical Diseases, 2008
- The Challenges of Chagas Disease— Grim Outlook or Glimmer of Hope?PLoS Medicine, 2007
- Are insecticide-impregnated dog collars a feasible alternative to dog culling as a strategy for controlling canine visceral leishmaniasis in Brazil?International Journal for Parasitology, 2004
- Chagas' disease challengeThe Lancet, 2000
- Onchocerciasis and Chagas' disease control: the evolution of control via applied research through changing development scenariosBritish Medical Bulletin, 1998