The coati (Nasua nasua, Carnivora, Procyonidae) as a reservoir host for the main lineages of Trypanosoma cruzi in the Pantanal region, Brazil

Abstract

We have focused on the role played by a carnivore, the coati (Nasua nasua), in the transmission cycle of Trypanosoma cruzi in the Brazilian Pantanal biome. We collected data during 2000/01 and 2005-07. Prevalence and pattern of T. cruzi infection were determined by serological tests and hemoculture. Isolates were characterized by miniexon molecular assay. Our results demonstrate that T. cruzi transmission cycle among coatis in the southern Pantanal seems to be well established, as we found high serum prevalences and high parasitemias throughout the two studied periods. Single infections by TCII (32.1%), TCI (28.0%) and Z3 (7.1%) were observed. Mixed infections by TCI/TCII (10.7%) and TCI/Z3 (3.6%) were also detected. Distinct genotypes of T. cruzi could be recovered during the 8 months follow-up of the same animals. As free-living coatis have high densities and inhabit all habitats, they may play an important role in the maintenance and dispersion of the main T. cruzi subpopulations. Considering that the Pantanal connects some of the major biomes of South America, it may be acting as a corridor for the spread of the main T. cruzi subpopulations. Our data give support that predator-prey links are important mechanisms for T. cruzi transmission and perpetuation in the wild.

Seroprevalence ofTrypanosoma cruziAmong Eleven Potential Reservoir Species from Six States Across the Southern United States

“…Striped skunks had been shown to be experimentally susceptible to T. cruzi (Davis et al 1980), and antibodies to T. cruzi had been detected in a single striped skunk from Los Angeles, CA (Ryan et al 1985). The positive ringtail was not unexpected, due to their relatedness to other procyonids (e.g., raccoons, coati [Nasua nasua], and kinkajou [Potos flavus]) that are naturally infected with T. cruzi (Travi et al 1994, Herrera et al 2008. Also, ringtails use tree cavities and abandoned housing as den sites (Poglayen-Neuwall andToweill 1988, Koepfli et al 2007), which are common habitats for triatomine bug vectors and other potential reservoirs of T. cruzi.…”

Vetores da doença de Chagas no Brasil

“…O acompanhamento de quatis re-capturados mostra que a infecção por T. cruzi pode apresentar altas parasitemias e ser mantida por longo tempo. Nessa região, esses animais apresentam elevada abundância relativa, o que reforça ainda mais sua importância como reservatório amplificador das populações parasitárias nessa região (Herrera et al 2008b).…”

Triatominae (Hemiptera, Reduviidae) in the Pantanal region: association with Trypanosoma cruzi, different habitats and vertebrate hosts

“…Thus, the sylvatic cycles of T. cruzi can be considered to be unpredictable and multivariable complex systems that varyingly interact with different host species (mammals and triatomine bugs), leading to the genetic plasticity of T. cruzi. In the Pantanal region, coatis were found to be naturally infected with several subpopulations of T. cruzi (15) . Although not many species are endemic to the Pantanal region, compared with the species abundance at Atlantic Forest and Brazilian Cerrado, the biodiversity of Pantanal region is considerably high (21) .…”

“…In this regard, coati nests would act as an important link in the complex cycle of T. cruzi transmission in the Pantanal region, because coatis have high levels of T. cruzi prevalence and parasitemias (15) and are found together with triatomine bugs infected by T. cruzi in their nests. When coatis are generalists regarding their diet (47) , they become infected by T. cruzi by eating infected triatomine bugs, regardless of the classical vector transmission routes.…”

“…The life cycle of T. cruzi in the Pantanal wetland is complex and has a dynamic profi le, because (a) T. cruzi infection has been described in a broad range of wild mammal species (12) (14) (15) , (b) some wild triatomine bug species are found in different ecological niches, (c) different subpopulations of T. cruzi circulate in the study area (15) , and (d) constant environmental changes through deforestation occur to implement intensive cattle farming.…”