Trypanosoma Cruzi and Leishmania Sp. Infection in Wildlife From Urban Rainforest Fragments in Northeast Brazil

Abstract

: Trypanosoma cruzi and Leishmania sp. are important protozoan parasites for humans and animals in the Americas, causing Chagas disease and cutaneous or visceral leishmaniasis, respectively. These vector-borne diseases affect permanent and transient populations in developing tropical countries that exhibit favorable conditions for the perpetuation of the parasite cycle. Our objective was to investigate the occurrence of infection with these parasites in wild animals from urban rainforest fragments in the city of Salvador, the largest city in the northeast region of Brazil. Sixty-five wild animals were captured, clinically examined, and sampled for parasite detection by PCR and culture. Ten different mammalian genera were identified, being 58% (38/65) marsupials. The prevalence of T. cruzi and Leishmania sp. infections was 13% and 43%, respectively. Both parasites were detected by PCR in 11% (7/65), three of which were also double infected as determined by culture. Among the 28 animals found infected with at least one parasite (43%, 28/65), 68% (19/28) were marsupials, two specimens were Callithrix sp. (7%), and one was Trinomys sp. (3%). Most infected animals (89%) had no clinical signs of disease. We found that healthy free-living animals from urban rainforest fragments harbored pathogenic trypanosomatids and should be included in epidemiology studies of diseases in big cities in tropical countries, as these cities grow and engulf rainforest remnants.

In the heart of the city: Trypanosoma cruzi infection prevalence in rodents across New Orleans

“…For example, we detected T. cruzi in all five of the rodent host species found in New Orleans [39], which parallels reports of T. cruzi infections in multiple rodent and other mammalian host species trapped in residential neighborhoods in the Yucatan [48] and Caracas Valley [24,25]. We also found a comparable level of overall infection prevalence in New Orleans [25,48,49]. It is notable, however, that we did not find differences in prevalence among host species.…”

“…Likewise, no evidence of infection was found in rodents trapped in forest fragments in Salvador (Brazil), where only Didelphis opossums were found to carry T. cruzi [49]. More extensive surveys of urban hosts in endemic areas might reveal greater parity in infection prevalence; however, as most prior work has involved comparisons among a much smaller number of trapped individuals than the number of rodents assayed for this study [24,25,[48][49][50]. On the other hand, more extensive surveys targeting less abundant species native to New Orleans (i.e.…”

“…For example, surveys in the Yucatan and Caracas Valley found that T. cruzi was more prevalent in roof rats than in house mice [25,48]. Likewise, no evidence of infection was found in rodents trapped in forest fragments in Salvador (Brazil), where only Didelphis opossums were found to carry T. cruzi [49]. More extensive surveys of urban hosts in endemic areas might reveal greater parity in infection prevalence; however, as most prior work has involved comparisons among a much smaller number of trapped individuals than the number of rodents assayed for this study [24,25,[48][49][50].…”

“…cotton rats and rice rats) Detection of infected rodents in all of our study areas indicates that transmission among zoonotic hosts is local and widespread across New Orleans. Though the possibility of local transmission has been raised by prior work on other urban commensal and domestic mammal species [23], it has been difficult to exclude alternatives like geographical transience and interactive connectivity between reservoirs and vectors [20] located in peripheral habitats [49]. In part, this is because limited trapping as well as a focus on hosts with large range sizes and high mobility has prevented identification of the point(s) of infection.…”

PathogenicLeptospiraspecies are widely disseminated among small mammals in Atlantic Forest biome

“…in Didelphis aurita (Lopes, Menna-Barreto, Pavan, Pereira, & Roque, 2018) and in Trinomys sp. (Trüeb et al, 2018); Hantavirus (Juquitiba viral genotype) in Akodon cursor and Oligoryzomys nigripes (De Oliveira et al, 2017); and Toxoplasma gondii in Akodon spp., O. nigripes and D. aurita (Gennari et al, 2015), their role in the maintenance and shedding of leptospires remains to be elucidated. Some serosurveys for detecting Leptospira spp.…”