Banca de DEFESA: NATHAN RAVI MEDEIROS HONORATO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : NATHAN RAVI MEDEIROS HONORATO
DATE: 03/03/2020
TIME: 09:00
LOCAL: POP Centro de Convivência
TITLE:

EVALUATION OF THE PRESENCE OF TRIATOMIES AND DISTRIBUTION OF DTUs from Trypanosoma cruzi IN DIFFERENT MESOREGIONS OF RIO GRANDE DO NORTE, BRAZIL

KEY WORDS:

Triatoma brasiliensis. Peridomicile. Trypanosoma cruzi. Discrete Typing Units. Mixed infection

PAGES: 75
BIG AREA: Ciências Biológicas
AREA: Parasitologia
SUMMARY:

This work evaluated the presence of triatomines, entomological indicators of triatomines and the distribution of the different typing units (DTUs, from the English Discrete Typing Units) of Trypanosoma cruzi isolated from vectors in different mesoregions of the state of Rio Grande do Norte (RN). The captures of the triatomines were carried out in rural areas of 21 municipalities, 71 rural communities and 345 household units in the period from 2015 to 2019. Genotyping was carried out using the mitochondrial gene markers of subunit 2 of cytochrome oxidase (CO II), divergent domain D71 of the 24Sα gene of the ribosomal DNA (rDNA) and intergenic spacer of the miniexon genes (SL-IR). Infestation was observed in 7.5% (26/345) of households and in 16.2% (56/345) of the surveyed households. The presence of nymphs in the home was observed in 94.7% (45/47) of the infested home units, indicating colonization in this environment. A total of 1,084 triatomines were captured in anthropic and wild environments, with Triatoma brasiliensis (84.5%) being the most found species, followed by Triatoma pseudomaculata (14.9%), Panstrongylus lutzi (0.5%), Rhodnius nasutus (0.1%). T. brasiliensis was the only species found in the home, peridomicile and wild environment, and also infested the largest variety of ecotopes. Natural infection by T. cruzi was observed in 11% (96/872) triatomines, with T. brasiliensis being the species with the highest number of specimens (95.0%). Of the 96 infected triatomines, it was possible to isolate the parasite from 33 (34.4%) samples, all of which were genotyped. DTU I: haplotype A in COII, rDNA 2 and SL-IR with 150 bp was identified in 51.5% (17/33) of the parasite isolates in the peridomicile infecting T. brasiliensis in the three studied mesoregions, and T. pseudomaculata, in West mesoregion. DTU II: haplotype C in COII, rDNA 1, SL-IR with 150 bp was observed in 9.1% (3/33) of isolates in T. brasiliensis only in the Central mesoregion both in the home and in the wild. While DTU III: haplotype B in COII, rDNA 2, SL-IR with 200 bp was in 27.3% (9/33) of the samples and was also found in all mesoregions, in the home area in the West mesoregion, in wild areas in the Center and peridomicile in Agreste. The proximity and even overlap of areas of occurrence of the genotypes was observed in several areas. In Caicó, this fact was evidenced by the detection of mixed infections with TcI and TcII. These results show that T. brasiliensis remains the species with the greatest epidemiological importance in the semi-arid region of RN, due to its wide geographical distribution, high degree of adaptation to different environments, ecotopes, high rate of natural infection by T. cruzi and the diversity of DTUs, and reinforce the need for continuous entomological surveillance in the state, in order to prevent contact of this species with humans and domestic animals.

BANKING MEMBERS:
Presidente - 1218940 - ANTONIA CLAUDIA JACOME DA CAMARA
Externa à Instituição - DANIELLA CASTANHEIRA BARTHOLOMEU
Interna - 1715271 - RENATA ANTONACI GAMA