Dados do Trabalho

Título

Detection of Trypanosoma cruzi DTU TcII and Trypanosoma rangeli in Bothrops alternatus from Mato Grosso do Sul, Brazil

Introdução

In recent decades, the emergence and re-emergence of zoonoses has become frequently associated with spillover events. This phenomenon was already described in Trypanosoma species, which has proven to be more generalist than previously considered. Unlike mammalian trypanosomes, little is known about the Trypanosoma species that infect reptiles.

Objetivo (s)

To investigate the infection by Trypanosoma spp. in snakes rescued from different locations in Mato Grosso do Sul State and maintained in captivity in UCDB bioterium (SISBIO 78932-1, CEUA-UCDB 006/2021, CEUA-FIOCRUZ 006/2019).

Material e Métodos

A total of 181 blood samples (including second samplings) were collected from 152 individuals of five snake species (Boa constrictor, Bothrops alternatus, B. mattogrossensis, B. moojeni and Crotalus durissus) maintained in captivity for up to 20 years. These samples were subjected to hemocultures (NNN/LIT medium), and fresh blood and blood smears (stained with Panótico Rápido kit) examinations. Positive hemocultures were characterized by PCR (SSU rDNA gene), followed by sequencing analysis (Sanger method). Experimental infection was performed in six Swiss mice intraperitonially inoculated with 2x105 T. rangeli parasites and observed by fresh blood exam every 48hs.

Resultados e Conclusão

All fresh blood exams and blood smears were negative, but three snakes (1.97%) showed positive hemocultures, all from B. alternatus. Positive cultures had an aliquot immediately separated (first aliquot) for molecular characterization. Due to fungal contamination, two were inoculated and one was re-isolated from blood of Swiss mice. Sequencing of the three first aliquot samples revealed 100% identity with Trypanosoma cruzi DTU TcII (access MH411637; n=2) and Trypanosoma rangeli lineage A (access MN381027; n=1). The parasites isolated from mice were characterized as T. rangeli lineage A, pointing to a mixed infection because the first aliquot of this culture was previously characterized as T. cruzi. Mice experimentally infected exhibited a pre-patent period of 9±2 days, and parasitemia duration of 15±9 days, reaching the peak on day 17±3. Infection by T. cruzi and T. rangeli, recognized as multi-host mammalian parasites, can result in long-lasting parasitemia in snakes maintained in captivity for up to six years. This is the first report of T. rangeli infection in reptiles and the first of T. cruzi in B. alternatus, broadening the discussions on the ability of these Trypanosoma species to infect distinct animals as mammals and reptiles.

Palavras Chave

spillover; snakes; Trypanosoma cruzi; Trypanosoma rangeli; diagnosis