Banca de DEFESA: MARICÉLIA DE AQUINO SANTANA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MARICÉLIA DE AQUINO SANTANA
DATE: 19/05/2026
TIME: 14:00
LOCAL: REMOTA
TITLE:

THE VECTOR ECOLOGY AND GENETIC DIVERSITY OF TRYPANOSOMA CRUZI IN THE SEMI-ARID REGION OF PIAUÍ: IMPLICATIONS FOR EPIDEMIOLOGY

KEY WORDS:

Trypanosoma cruzi. Chagas disease. Vector transmission. Natural infection. Genotyping. Triatoma brasiliensis complex.

PAGES: 71
BIG AREA: Ciências da Saúde
AREA: Farmácia
SUMMARY:

Introduction: Chagas disease transmission is associated with the presence of infected triatomines and the circulation of Trypanosoma cruzi genotypes in anthropic and sylvatic environments. The adaptation of vector species to intra- and peridomestic settings increases the risk of human infection and hinders control measures. In this context, identifying predominant species, colonized ecotopes, and circulating Discrete Typing Units (DTUs) is essential for improving entomological surveillance. Objective: To evaluate the occurrence of triatomines, natural infection by T. cruzi, and the distribution of DTUs in municipalities in southeastern Piauí State, Brazil. Methods: Active searches for triatomines were conducted in rural areas of nine municipalities, encompassing 24 communities and 281 households, between July 2022 and November 2023. Triatomine fauna, infection by trypanosomatids, blood meal sources, and genetic characterization of T. cruzi were analyzed. Genotyping was performed using the COII, 24Sα rDNA (D7 domain), and miniexon gene (SL-IR) markers. Results: A total of 661 triatomines were captured, with predominance of Triatoma brasiliensis (92.1%), followed by Triatoma pseudomaculata (7.3%), Panstrongylus lutzi (1%), and Rhodnius sp. (0.4%). T. brasiliensis was found in intra-, peridomestic, and sylvatic environments, whereas T. pseudomaculata was restricted to the peridomicile. Natural infection by T. cruzi was detected in 12% (67/556), with 11.1% in T. brasiliensis. Among infected specimens, 47.7% (32/67) were successfully isolated and genotyped, revealing the presence of DTUs TcI (9.4%), TcII (75%), and TcIII (9.4%), as well as mixed infections (TcII+TcIII), including in domestic environments. Conclusion: The findings indicate active transmission in the semi-arid region of Piauí, with T. brasiliensis playing a central role, associated with its wide distribution, high infection rates, genetic diversity of the parasite, and generalist feeding behavior, reinforcing the need for integrated entomological surveillance strategies.

COMMITTEE MEMBERS:
Externa à Instituição - DANIELLA CASTANHEIRA BARTHOLOMEU - UFMG
Externa ao Programa - 1714243 - DANIELLA REGINA ARANTES MARTINS SALHA - nullExterno à Instituição - ELIANE LAGES SILVA - UFTM
Presidente - ***.985.294-** - LUCIA MARIA DA CUNHA GALVAO - UFRN
Externa à Instituição - MARIA TEREZINHA BAHIA - UFOP