Molecular Epidemiology of Trypanosomatids and Trypanosoma cruzi in Primates from Peru

Abstract

We determined the prevalence rate and risk of infection of Trypanosoma cruzi and other trypanosomatids in Peruvian non-human primates (NHPs) in the wild (n = 126) and in different captive conditions (n = 183). Blood samples were collected on filter paper, FTA cards, or EDTA tubes and tested using a nested PCR protocol targeting the 24Sα rRNA gene. Main risk factors associated with trypanosomatid and T. cruzi infection were genus and the human-animal context (wild vs captive animals). Wild NHPs had higher prevalence of both trypanosomatids (64.3 vs 27.9%, P < 0.001) and T. cruzi (8.7 vs 3.3%, P = 0.057), compared to captive NHPs, suggesting that parasite transmission in NHPs occurs more actively in the sylvatic cycle. In terms of primate family, Pitheciidae had the highest trypanosomatid prevalence (20/22, 90.9%) and Cebidae had the highest T. cruzi prevalence (15/117, 12.8%). T. cruzi and trypanosomatids are common in Peruvian NHPs and could pose a health risk to human and animals that has not been properly studied.

Keywords: Chagas; Epidemiology; Non-human primates; Prevalence; Trypanosoma cruzi; Trypanosomatids.

Figure 1

Map of Peru showing the locations where captive (n = 183, circles) and wild (n = 126, triangles) NHPs were sampled: Nueva Esperanza (n = 118), Yurimaguas (n = 68), Lima (n = 28), Pucallpa (n = 26), Puerto Maldonado (n = 26), Cuzco (n = 18), Moyobamba (n = 16), Sol Naciente (n = 8) and Iquitos (n = 1). Biological samples from wild NHPs were collected in two indigenous communities in the Northern Peruvian Amazon.

Figure 2

Most parsimonious tree build using recursive partitioning to identify major risk factors linked to the presence of trypanosomatids in NHPs. Wild NHPs and NHPs from wet markets, and genera Alouatta, Lagothrix, Cacajao, Pithecia, Cebus, Samiri and Callicebus have a significantly higher risk of trypanosomatid infection. The most parsimonious tree model explained 35.1% of observed variability.

Figure 3

Most parsimonious tree build using recursive partitioning to identify major risk factors linked to the presence of Trypanosoma cruzi in NHPs. Wild NHPs, and genus Cebus, Saimiri and Callicebus have a significantly higher risk of T. cruzi infection. The most parsimonious tree model explained 23.1% of observed variability.