Urban vectors of Chagas disease in the American continent: A systematic review of epidemiological surveys

Abstract

Background Chagas is a complex and multidimensional socio-environmental health phenomenon, in which different components converge and interact. Historically, this disease was associated with insect vectors found in the rural environment. However, in the Americas, we are currently facing a new paradigm, in which different scenarios allow maintaining the vectorial transmission of the parasite through triatomine populations that either occasionally enter the dwellings or colonize urban environments. Methodology/Principal findings Records of scientific reports available in the PubMed and LILACS search engines were retrieved, using three criteria according to the main triatomine genera of epidemiological importance and to the general scientific production on Chagas disease in urban contexts. Results showed that records on the occurrence of vectors in urban dwellings began to increase in the last three decades. Results also showed that the main species of triatomines collected inside dwellings (18 in total) belong mainly to the genera Triatoma and Panstrongylus, with most species (16/18, 88.8%) infected with the parasite, and that infestation of triatomine species occurs in all types of cities (small, medium and large, including megalopolises), from Argentina to the USA. Conclusions/Significance Urban Chagas represents a new challenge that adds a different dimension to the problem of Chagas disease due to the particular characteristics of the lifestyle in urban agglomerates. The new scenario will require adaptations of the programs of control of vector to this shift from rural to urban settlements.

Interesting case from Argentina: Kidney transplant recipient with skin lesions—A Latin American perspective

“…Experts highlight that these vectors have demonstrated extraordinary adaptability to new ecological niches and colonies of these vectors have been observed in buildings within highly developed urban environments, such as Houston (USA), 51 Caracas (Venezuela), and Ceará (Brazil). 52 The Chagas Disease Guidelines for transplant recipients and their donors discuss three main topics: (1) the pretransplant assessment and management of donor and the candidate, (2) the post-transplant monitoring, and (3) the treatment of active infection. With regards to the screening of the donor and the transplant candidate, there is a general agreement among different international guidelines.…”

“…These triatomine vectors are responsible for the spread of the disease and are found throughout Latin America, usually nesting in rural houses with unsmoothed, adobe walls, thatched roofs, and cluttered interiors. Experts highlight that these vectors have demonstrated extraordinary adaptability to new ecological niches and colonies of these vectors have been observed in buildings within highly developed urban environments, such as Houston (USA), 51 Caracas (Venezuela), and Ceará (Brazil) 52 …”

Identifying Barriers and Facilitators for Home Reconstruction for Prevention of Chagas Disease: An Interview Study in Rural Loja Province, Ecuador

“…Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae: Trypanosoma) (Chagas, 1909), the etiological agent of Chagas disease, is transmitted through the excreta (feces and urine) of triatomine insects (Hemiptera: Reduviidae: Triatominae), known in English as 'kissing bugs,' in Ecuador as chinchorros, or by many local names in different countries [6]. Although there is evidence that these insects are increasingly found in urban settings in Central and South America [7], more commonly, these insects inhabit poorly constructed homes in rural areas, living in the cracks of the walls, ceilings, and floors of adobe houses [8]. These homes are prevalent in rural Ecuador, and they facilitate infection [9].…”