Triatomines in dwellings and outbuildings in an endemic area of Chagas disease in northeastern Brazil

Abstract

Introduction:The present study identified the triatomines collected in intra and peri-domestic environments, observed the occurrence of Trypanosoma cruzi infection in triatomines and correlated this information with housing conditions and the fauna associated with the rural areas of the City of Itabaianinha, located in the State of Sergipe, Brazil. Methods: Quarterly visits were conducted between March 2009 and March 2010, and the homes to be visited for the active search of insects were determined by random selection. In each housing unit, the insects were collected by a manual search with a metal clip and flashlight to inspect openings and cavities, with a collection time of one hour/home/individual. The Pirisa® dislodge chemical was used to force the insects to leave their ecotopes. Analysis of the intestinal contents of triatomines was performed in the laboratory to establish the presence of Trypanosomatidae. Results: Of the 103 dwellings surveyed, 17.5% were infested with Panstrongylus megistus. The village of Mutuca exhibited the highest infestation rate (38.1%). All the villages with relevant infestation rates were situated in the northern area of the city. The highest percentage of vector infection was found in the village of Água Boa (56.5%). The rural dwellings were found to be primarily brick or wooden house with or without roughcast or plastered walls, and the outbuilding most frequently associated with triatomines was the chicken run. Conclusions: These results emphasise the need for broader vector control and surveillance and for educational campaigns in the context of the Chagas Disease Control Program.

Triatomine Fauna and Recent Epidemiological Dynamics of Chagas Disease in an Endemic Area of Northeast Brazil

“…For municipalities at potential risk for the transmission of CD, the profound environmental changes caused by agricultural production combined with the use of pesticides for controlling insects and other anthropogenic modifications should also be considered. In addition, the consequent reduction of native vegetation coverage and the preferential ecotype of the triatomines forced the vectors to move to the vicinity of human dwellings [ 22 , 40 ]. As a result, the municipality of Cristinápolis, which is located in an area with only 9.64% of its original forest cover and eucalyptus production, was included even though no occurrence of vectors has been reported, but cases of positive serology for human CD were recorded [ 27 , 41 ].…”

“…Another common feature in the interior of this state is the construction of home annexes for housing animals (e.g., cattle, goats, pigs, and chickens). Lima et al [ 22 ] found that the presence of positive triatomines in the rural properties of Sergipe is related to the variety of reared animals and the number of home annexes built to house these animals. Figueiredo et al [ 44 ] observed a strong influence of ecological aggressions on the migration of triatomines toward man-made artificial ecotopes, because these places provide easy access to food, shelter, and protection against natural enemies.…”

Avaliação da ocorrência de infestação por triatomíneos em ambientes domicilares do município de Aurora-CE no período entre 2008 a 2012

“…4 O processo de domiciliação triatomínica ocorre quando estes insetos abandonam seu habitat natural devido à destruição ou modificação deste e migra para residências onde há criação de animais domésticos em peridomicílio com estruturas precárias proporcionando fonte alimentar e abrigo, esse processo influencia a ocorrência e transmissão do Trypanosoma cruzi, uma vez que promove o contato permanente entre os vetores, animais e os seres humanos. 5,6 Os processos envolvidos na domiciliação dos vetores da doença de Chagas são divergentes, alguns consideram um simples oportunismo devido à escassez das fontes naturais de alimento e outros acreditam tratar-se de processo gradual de adaptação, sujeito à seleção natural 1 Conclui-se que há colonização em peridomicílio pela espécie T. Pseudomaculata no município de Aurora e que apesar do baixo índice de infecção natural pelo T. cruzi, apresentada pela espécie T. pseudomaculata, a população local encontra-se susceptível, uma vez que a espécie T. pseudomaculata encontra-se próxima a T. brasilienses e esta é considerada fonte primária de infecção.…”

First Report of Acute Chagas Disease by Vector Transmission in Rio De Janeiro State, Brazil

“…Although the prevalence of CD has decreased in the last decades, a recent meta-analysis estimated CD prevalence in Brazil to be near 2.4% or about 4.6 million Brazilians infected by T. cruzi 15 . However, other transmission mechanisms may keep CD as a public health problem such as the ingestion of food contaminated with T cruzi , causing outbreaks of acute CD and transmission by native vectors in different areas of Brazil 1 , 3 , 5 , 12 , 14 , 21 , 22 , 23 , 27 , 28 .…”