Trypanosoma cruzi and Trypanosoma rangeli co-infection patterns in insect vectors vary across habitat types in a fragmented forest landscape

Abstract

SUMMARYThe transmission of parasites can be influenced by their co-occurrence with other parasites, in some cases increasing or reducing transmission.Trypanosoma cruzi, aetiologic agent of Chagas disease, often co-occurs withTrypanosoma rangeli, a parasite not pathogenic for mammal hosts. Both parasites can reduce the fitness of their insect vectors (the triatomine bugs; Hemiptera: Reduviidae), withT. rangelibeing more pathogenic for some species. Here, we study the prevalence ofT. cruziandT. rangeliin the triatomineRhodnius pallescensacross a heterogeneously transformed landscape in Panamá. We found that singleT. rangeliinfections were more common in contiguously forested habitats, while singleT. cruziinfections predominated in anthropogenically disturbed habitats.Trypanosoma cruzi–T. rangelico-infections were more common in contiguous forests and in peridomiciliary areas. Furthermore, adult insects were more likely to be co-infected than nymphs. Our results suggest that human-mediated landscape transformation might have increased the predominance of single infections withT. cruziwithin vectors. An important mechanism driving changes in trypanosome infection patterns in triatomines at a landscape scale includes alterations in host species composition that may vary with different degrees of deforestation. Trypanosome co-infection may also confer a survival advantage forR. pallescensto and/or throughout adulthood.

Surveillance and genotype characterization of zoonotic trypanosomatidae in Didelphis marsupialis in two endemic sites of rural Panama

“…Lower T. rangeli compared to T. cruzi infection in opossums correlates with previous studies in the vector R. pallescens describing a higher proportion of T. cruzi- infected vectors compared to T. rangeli, and similar T. cruzi-T. rangeli co-infection rates across habitat types ( Gottdenker et al, 2016 ). Interestingly, studies from the same geographic region of LP show T. rangeli infection is relatively common in children ( Saldaña et al, 2005 ).…”

A darker chromatic variation of Rhodnius pallescens infected by specific genetic groups of Trypanosoma rangeli and Trypanosoma cruzi from Panama

“…Recently, Peterson & Graham [ 27 ] also called attention to the lack of sufficient evidence to support the assumption that T. rangeli is pathogenic to all Rhodnius species. On the other hand, Gottdenker et al [ 28 ] postulated that T. rangeli / T. cruzi co-infection may confer a survival advantage for R. pallescens throughout adulthood. The same conclusion was reached by Peterson & Graham [ 27 ] who observed that R. prolixus experimentally co-infected with T. cruzi and T. rangeli have higher survival than bugs infected with just one of the species.…”

Trypanosoma cruzi–Trypanosoma rangelico-infection ameliorates negative effects of single trypanosome infections in experimentally infectedRhodnius prolixus

“…Reported prevalences of T. cruzi–T. rangeli co-infection in field-caught triatomines have been found to be higher than single infections of T. rangeli in R. prolixus (Groot, 1951; Vallejo et al 1988), R. pallescens (Pineda et al 2008; Calzada et al 2010; Gottdenker et al 2016); and R. colombiensis (Pavia et al 2007), which would support the idea of a co-infection advantage for T. rangeli (Fig. 1).…”