The main sceneries of Chagas disease transmission. The vectors, blood and oral transmissions - A comprehensive review

Abstract

This review deals with transmission of Trypanosoma cruzi by the most important domestic vectors, blood transfusion and oral intake. Among the vectors, Triatoma infestans, Panstrongylus megistus, Rhodnius prolixus, Triatoma dimidiata, Triatoma brasiliensis, Triatoma pseudomaculata, Triatoma sordida, Triatoma maculata, Panstrongylus geniculatus, Rhodnius ecuadoriensis and Rhodnius pallescens can be highlighted. Transmission of Chagas infection, which has been brought under control in some countries in South and Central America, remains a great challenge, particularly considering that many endemic countries do not have control over blood donors. Even more concerning is the case of non-endemic countries that receive thousands of migrants from endemic areas that carry Chagas disease, such as the United States of America, in North America, Spain, in Europe, Japan, in Asia, and Australia, in Oceania. In the Brazilian Amazon Region, since Shaw et al. (1969) described the first acute cases of the disease caused by oral transmission, hundreds of acute cases of the disease due to oral transmission have been described in that region, which is today considered to be endemic for oral transmission. Several other outbreaks of acute Chagas disease by oral transmission have been described in different states of Brazil and in other South American countries.

2 nd Brazilian Consensus on Chagas Disease, 2015

“…Uncontrolled human migration, environmental degradation, climate change, high population concentrations in urban areas, and precarious socio-economic conditions (housing, education, sanitation, and income, among others) are determinants and social conditioning factors for the transmission of T. cruzi (1) (10) (11) (19) (20) (21) (22) (23) . Infected populations are vulnerable to varying degrees of neglect, expressed by overlapping and increased exposure to other diseases, conditions and injuries; lower coverage for preventive interventions; a higher likelihood of illness; less access to a network of health services, to secondary and tertiary health care, and to other services; poor quality of primary care services; lesser likelihood of receiving essential treatments; and greater likelihood of developing severe forms of the disease with increased risk of progression to death (24) .…”

“…On the other hand, active surveillance should be carried out obligatorily in municipalities with residual foci of T. infestans (23) (39) .…”

“…João Carlos Pinto Dias [1] , Alberto Novaes Ramos Jr [2] , Eliane Dias Gontijo [3] , Alejandro Luquetti [4] , Maria Aparecida Shikanai-Yasuda [5] , José Rodrigues Coura [6] , Rosália Morais Torres [3] , José Renan da Cunha Melo [3] , Eros Antonio de Almeida [7] , Wilson de Oliveira Junior [8] , Antônio Carlos Silveira [9] , Joffre Marcondes de Rezende [10] , Fabiane Scalabrini Pinto [11] , Antonio Walter Ferreira [12] , Anis Rassi [13] , Abílio Augusto Fragata Filho [14] , Andréa Silvestre de Sousa [15] , Dalmo Correia [16] , Ana Maria Jansen [6] , Glaucia Manzan Queiroz Andrade [3] , Constança Felícia De Paoli de Carvalho Britto [6] , Ana Yecê das Neves Pinto [17] , Anis Rassi Junior [13] , Dayse Elisabeth Campos [18] , Fernando Abad-Franch [1] , Silvana Eloi Santos [3] , Egler Chiari [19] , Alejandro Marcel Hasslocher-Moreno [15] , Eliane Furtado Moreira [20] , Divina Seila de Oliveira Marques [21] , Eliane Lages Silva [22] , José Antonio Marin-Neto [23] , Lúcia Maria da Cunha Galvão [19] , Sergio Salles Xavier [24] , Sebastião Aldo da Silva Valente [17] , Noêmia Barbosa Carvalho [25] , Alessandra Viana Cardoso [26] , Rafaella Albuquerque e Silva [26] , Veruska Maia da Costa [26] , Simone Monzani Vivaldini …”

High-Resolution Molecular Typing ofTrypanosoma cruziin 2 Large Outbreaks of Acute Chagas Disease in Colombia

“…Additionally, qPCR detected the parasite in reservoirs, insects, and heart tissue from both patients who died, providing more information for analysis of possible sources of infection. Regarding the reservoirs, it is important that T. cruzi DNA was detected in all samples of blood and odoriferous gland secretions from the opossums, revealing didelphids as a potential source of infection; this reservoir has been described elsewhere as one of the main sources of T. cruzi infection in outbreaks related to oral transmission [1,4,8]. In addition, it is important to emphasize that, in both outbreaks, specimens from dogs tested positive by qPCR, indicating active transmission of the parasite from the sylvatic to the domestic environment.…”

Minimum free energy predicted base pairing in the 39 nt spliced leader and 5’ UTR of calmodulin mRNA from Trypanosoma cruzi: influence of the multiple trans-splicing sites

“…As parasite, T. cruzi accomplishes its life cycle by moving from invertebrate to vertebrate hosts (Coura 2014). This transition submits the parasite to physical and chemical shifts that include wide variations in temperature, nutrient availability, osmotic and environmental pressure.…”