Improving houses in the Bolivian Chaco increases effectiveness of residual insecticide spraying against infestation with Triatoma infestans, vector of Chagas disease

While the control of the major Chagas' disease vector Triatoma infestans has been achieved in many endemic areas of Brazil, data from the inception of the control program in the Triângulo Mineiro (1976-79) suggest that re-infestation by triatomines occurs under certain favorable conditions. The percentage of houses infested in 500 communities of the Triângulo Mineiro region is compared for two years: 1976 and 1979, using linear regression models. Controlling for three major triatomine vectors, household crowding, house demolition and construction, and infested out-buildings are all independent covariates of house infestation in these communities. While several household factors have been suggested as correlates of infestation, the control program focuses on community-level reductions in infestation, but intra-community or regional comparisons have heretofore been unfeasible. Computerized data are becoming available to identify communities at high risk for re-infestation, and for targeting control-program activities.

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Identifying Current and Missing Knowledge in the Control of Pyrethroid-Resistant Triatoma infestans, Vector of Chagas Disease

Global Journal of Health Science ◽

10.5539/gjhs.v9n7p47 ◽

2017 ◽

Vol 9 (7) ◽

pp. 47

Author(s):

Gonzalo Roca Acevedo ◽

María Inés Picollo

Keyword(s):

Chagas Disease ◽

Chemical Control ◽

Rational Design ◽

Pyrethroid Resistance ◽

Triatoma Infestans ◽

Vector Transmission ◽

Pyrethroid Insecticides ◽

Blood Sucking ◽

Deltamethrin Resistance ◽

Metabolic Detoxification

Triatomines are blood-sucking bugs that occur mainly in Latin America. They are vectors of Trypanosoma cruzi, the parasite that causes Chagas disease. Chemical control of Chagas disease´s vectors by using pyrethroid insecticides has been highly successful for the elimination of domestic infestation and consequently the reduction of the vector transmission. However, at the beginning of the 2000s a decrease in the effectiveness of the chemical control of triatomines was detected in several areas from Argentina and Bolivia, particularly in the Gran Chaco eco-region.During the last 15 years, several studies demonstrated the evolution of insecticide resistance in Triatoma infestans and established the presence of different toxicological profiles, the autosomal inherence of resistance, the biological costs of deltamethrin resistance, the expression of deltamethrin resistance thorough the embryonic development, and the main mechanisms of resistance (target-site insensitivity and metabolic detoxification of insecticides).The emergence of pyrethroid resistance coupled with the usual difficulties in sustaining adequate rates of insecticide applications emphasize the need of incorporating other tools for integrated vector and disease control, such as the proposal of the organo-phosphorus insecticide fenitrothion as an alternative chemical strategy for the management of the resistance because it was effective against pyrethroid-resistant populations in laboratory and semi-field trials.New studies on the current situation of presence and spread of resistant populations of triatomines and the acceptance of the use of alternative insecticides are critical requirements in the implementation of strategies for the management of resistance and for the rational design of campaigns oriented to reducing the vector transmission of Chagas’ disease.

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Urban infestation by Triatoma infestans (Hemiptera: Reduviidae), an overlooked phenomena for Chagas disease in Argentina

Memórias do Instituto Oswaldo Cruz ◽

10.1590/0074-02760210056 ◽

2021 ◽

Vol 116 ◽

Author(s):

Yael Mariana Provecho ◽

María del Pilar Fernández ◽

Liliana Salvá ◽

Sergio Meli ◽

Florencia Cano ◽

...

Keyword(s):

Chagas Disease ◽

Triatoma Infestans

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Entomopathogenic nematodes (Heterorhabditidae and Steinernematidae), to control Triatoma infestans populations (Hemiptera: Reduviidae), Chagas disease vector

Biological Control ◽

10.1016/j.biocontrol.2021.104814 ◽

2021 ◽

pp. 104814

Author(s):

Daiana Pamela Eliceche ◽

María Fernanda Achinelly ◽

Carlos Silvestre ◽

María Victoria Micieli ◽

Gerardo Aníbal Marti

Keyword(s):

Chagas Disease ◽

Entomopathogenic Nematodes ◽

Triatoma Infestans ◽

Disease Vector

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The Octopamine Receptor Is a Possible Target for Eugenol-Induced Hyperactivity in the Blood-Sucking Bug Triatoma infestans (Hemiptera: Reduviidae)

Journal of Medical Entomology ◽

10.1093/jme/tjz183 ◽

2019 ◽

Author(s):

Mercedes M N Reynoso ◽

Alejandro Lucia ◽

Eduardo N Zerba ◽

Raúl A Alzogaray

Keyword(s):

Drosophila Melanogaster ◽

Latin America ◽

Essential Oils ◽

Chagas Disease ◽

American Cockroach ◽

Triatoma Infestans ◽

Aromatic Plants ◽

Blood Sucking ◽

Site Of Action ◽

Octopamine Receptor

Abstract Eugenol is a major component of the essential oils in cloves and other aromatic plants. In insects, it produces toxic effects and repellency, and there is evidence that its site of action is the octopamine receptor. The objective of the present study was to explore whether the octopamine receptor is involved in the hyperactivity produced by eugenol in the blood-sucking bug Triatoma infestans (Klug). This insect is the main vector of Chagas disease in Latin America. Four treatments were topically applied on third instar nymphs: 1) octopamine, 2) eugenol, 3) phentolamine hydrochloride (an antagonist of the octopamine receptor) followed by octopamine, and 4) phentolamine hydrochloride followed by eugenol. Both octopamine and eugenol hyperactivated the nymphs. However, pretreatment with phentolamine hydrochloride inhibited the hyperactivating effect of both compounds. These results are in agreement with previous works on Drosophila melanogaster (Meigen) (Diptera: Drosophilidae) and the American cockroach. They suggest that the octopamine receptor is a possible site of action for eugenol.

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First Report ofAprostocetus asthenogmus(Hymenoptera: Eulophidae) in South America and Parasitizing Eggs of Triatominae Vectors of Chagas Disease

Journal of Parasitology Research ◽

10.1155/2014/547439 ◽

2014 ◽

Vol 2014 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Claudiney Biral dos Santos ◽

Marcelo Teixeira Tavares ◽

Gustavo Rocha Leite ◽

Adelson Luiz Ferreira ◽

Leonardo de Souza Rocha ◽

...

Keyword(s):

South America ◽

Chagas Disease ◽

Biological Control Agent ◽

Control Agent ◽

Triatoma Infestans ◽

Disease Vectors ◽

Parasitoid Species ◽

Triatomine Species ◽

Chagas Disease Vectors ◽

First Time

We report for the first time the parasitism of eggs of two triatomine Chagas disease vectors,Triatoma infestansandT. vitticeps, by the microhymenopterous parasitoidAprostocetus asthenogmus. We also describe the first identification of this parasitoid in South America.A. asthenogmuswere captured near unparasitized triatomine colonies in the municipality of Vitória, state of Espírito Santo, Brazil, and placed into pots with recently laid triatomine eggs. After 24 days, we observed wasps emerging fromT. infestansandT. vitticepseggs. Several characteristics of this parasitoid species suggest that it could be a potential biological control agent of triatomine species.

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