Programa de Pós-Graduação em Biologia Parasitária
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Master Thesis Microevolução da resistência a antifúngicos em Candida (Candidozyma) auris selecionada pela exposição a fungicida(Universidade Federal do Rio Grande do Norte, 2025-12-16) Silva, Jéssica Karoline de Lima; Bastos, Rafael Wesley; Schinaider, Kássia Jéssica Galdino da Silva; https://orcid.org/0000-0001-7038-6306; http://lattes.cnpq.br/9304612925767591; https://orcid.org/0000-0001-6781-9617; http://lattes.cnpq.br/3333946080391361; http://lattes.cnpq.br/9374776495562259; Maia, Débora Castelo Branco de Souza Collares; https://orcid.org/0000-0002-6045-2354; http://lattes.cnpq.br/2373473099684326; Alves, Lysangela Ronalte; http://lattes.cnpq.br/2213128430343323Candida auris is an emerging pathogenic yeast frequently associated with hospital outbreaks and characterized by high levels of antifungal resistance. Fluconazole (FCZ) resistance is the most common, affecting up to 77% of isolates. One of the main challenges related to this species is understanding how its resistance mechanisms evolved. One hypothesis for the emergence of resistance is that extensive environmental use of agricultural azoles may select resistant strains that subsequently colonize or infect humans. In this study, we investigated whether exposure to the agricultural azole tebuconazole (TBZ) can select cross-resistance to FCZ in C. auris, and assessed the role of temperature in this adaptive process. Initially, tests were performed to determine the Minimum inhibitory concentrations (MICs) for FCZ and TBZ were determined for 39 isolates following CLSI (2021) guidelines. Overall, 41% (16/39) of the isolates were FCZ-resistant, and 38.5% (15/39) showed reduced susceptibility to TBZ. Notably, 94% (15/16) of the FCZ-resistant isolates also exhibited high MIC values for TBZ, meaning that all isolates with reduced sensitivity to TBZ were resistant to FCZ, reinforcing the initial hypothesis. Sensitivity to other azoles, such as itraconazole and posaconazole, was maintained in all isolates. To further explore this relationship, were conducted on microevolution experiments using the azole fungicide tebuconazole (TBZ) with three fluconazole-susceptible isolates from distinct geographic origins. Two cell populations from each isolate were serially exposed to fixed TBZ concentrations (16× MIC) at 30 °C and 37 °C. This serial exposure led to progressive or abrupt increases in MICs to TBZ and FCZ, especially at 37 °C. Phenotypic stability assessed after passages in drug-free medium revealed transitory cross-resistance in all isolates. Additional microevolution assays using stepwiseincreasing TBZ concentrations (up to 256 μg/mL) showed that some cell populations from two isolates acquired permanent cross-resistance. Together, these findings demonstrate that TBZ exposure can select either stable or transient fluconazole crossresistance in C. auris, and that this process depends on both incubation temperature and fungicide concentration.Master Thesis Potencial antibacteriano e modulação de resistência de cocristais obtidos a partir de Momordica charantia L.(Universidade Federal do Rio Grande do Norte, 2025-03-26) Mesquita, Larissa Esteves; Brandão, Deysiane Oliveira; Motta Neto, Renato; https://orcid.org/0000-0002-6112-7801; http://lattes.cnpq.br/6909091962347443; http://lattes.cnpq.br/0938468081530870; http://lattes.cnpq.br/9594341717619381; Melo, Maria Celeste Nunes de; Nunes, Luanne EugêniaNatural substances, especially those from medicinal plants, contain compounds capable of enhancing drugs, and are essential for the development of new medicines due to their low cost and easy access. Momordica charantia L. has proven antibacterial activity and potential for therapeutic applications. In the industrial setting, extracts can be used in cocrystals to enhance therapeutic effects. Therefore, this study aimed to evaluate the resistance-modulating activity and antimicrobial potency of cocrystals obtained from M. charantia L. extracts. During the methodological stage, the fruits were collected in São José da Mata (PB) and used to obtain five hydroalcoholic extracts in different proportions of water:ethanol (E1, E2, E3, E4, and E5). Antibacterial, phytochemical, and cytotoxicity analyses of the extract were performed. The cocrystals were formed by evaporation under reduced pressure and characterized by X-ray diffraction, differential scanning calorimetry and Fourier transform infrared spectroscopy. The modulating activity was evaluated by microdilution, with calculation of the fractional inhibitory concentration index (FICI). As results, Escherichia coli demonstrated greater sensitivity to extracts E1, E2 and E3 (0.125mg/mL). Phytochemical analysis revealed a higher concentration of tannins in relation to polyphenols and flavonoids in extracts E3, E4 and E5 (147,360±0.02µg/mL, 168,760±0.01µg/mL and 180,315±0.01µg/mL, respectively). The E3 extract was selected for cocrystal formation because it presented a lower Minimum Inhibitory Concentration (MIC), balanced phytochemical composition and adequate solvent ratio. In the tests with L929 fibroblasts and P815 mast cells, all concentrations tested reduced cell viability, but the moderate cytotoxicity of E3 does not preclude its therapeutic use. Structural analyses of E3 associated with Salicylic Carboxylic Acid (EX-SA) suggest cocrystal formation. The compound showed antimicrobial activity against E. coli, Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa, with a MIC of 1.04 mg/mL and synergism with Oxacillin, Amoxicillin+Clavulanate, Ceftriaxone and Meropenem. The results indicate that the EX-SA cocrystal not only improves the antimicrobial action of the extract, but also enhances the efficacy of conventional antibiotics, allowing the reduction of clinical doses. This finding reinforces the potential of M. charantia L. as a basis for new therapeutic formulations, opening perspectives for the development of more effective alternatives in combating bacterial resistance.Master Thesis Óleo essencial de Lippia grata Schauer (alecrim-do-mato): potencial inseticida e repelente contra Chrysomya megacephala (Fabricius, 1794) em condições laboratoriais(Universidade Federal do Rio Grande do Norte, 2025-03-21) Silva, Sarah Ruth Alves da; Gama, Renata Antonaci; Inácio, Cássio Lázaro Silva; https://orcid.org/0000-0002-1666-6646; http://lattes.cnpq.br/4910533645616566; https://orcid.org/0000-0002-8026-6022; http://lattes.cnpq.br/0179756405650744; https://orcid.org/0000-0002-8806-4855; http://lattes.cnpq.br/5436422261004898; Barbosa, Taciano de Moura; http://lattes.cnpq.br/0377384091253781; Barros, Veruska Cavalcanti; https://orcid.org/0000-0001-8483-4528; http://lattes.cnpq.br/9073798312880036Chrysomya megacephala (Fabricius, 1794) has a wide distribution and medical-veterinary relevance, acting as a vector of various pathogens. The control of this insect is predominantly carried out through synthetic insecticides, which have led to resistance selection and environmental impacts. In this context, interest in alternative strategies, such as the use of essential oils, is increasing. The literature indicates the insecticidal potential of Lippia grata (alecrim-do-mato) against insects of medical importance; however, its efficacy against muscoid dipterans, such as C. megacephala, remains little explored. This study evaluated the insecticidal and repellent activity of L. grata essential oil against C. megacephala under laboratory conditions. The essential oil of L. grata was obtained by hydrodistillation and tested at different concentrations. For insecticidal bioassays, 3 µL doses at concentrations of 0,859 g/mL, 0,644 g/mL, 0,429 g/mL, 0,214 g/mL, 0,150 g/mL, 0,128 g/mL, 0,107 g/mL, 0,053 g/mL, and 0,026 g/mL were applied to adults, and 0,859 g/mL, 0,644 g/mL, 0,429 g/mL, 0,214 g/mL, or 0,107 g/mL to third instar larvae (L3). Toxicity was assessed at different time intervals, and lethal concentrations (LC₅₀ and LC₉₀) were determined using Probit analysis. For repellency bioassays, the concentrations used were 0,859 g/mL, 0,429 g/mL, 0,214 g/mL, 0,107 g/mL and 0,053 g/mL, applied (1 mL) on filter paper, with activity evaluated using a specific experimental setup and within a defined period. The repellent concentrations (RC₅₀ and RC₉₀) were also determined by Probit analysis. Carvacrol (51,4%) was identified as the major compound in the oil. Adult mortality was dose-dependent (p<0,001), with total mortality observed at concentrations of 0,859 g/mL, 0,644 g/mL, 0,429 g/mL, 0,214 g/mL and 0,150 g/mL. The LC₅₀ and LC₉₀ values were 0,052 g/mL and 0,211 g/mL, respectively, after 48 hours. In the larvicidal bioassays, the doses of 0,859 g/mL and 0,644 g/mL showed significantly higher effects (p<0,0006) compared to the other concentrations. The LC₅₀ and LC₉₀ values were 0,202 g/mL and 7,42 g/mL, respectively. Color changes in immature stages were observed following treatment, along with high inhibition of adult emergence and deformed adults incompatible with life. In repellency bioassays, the 0.859 g/mL concentration exhibited a significantly superior repellent effect (p<0,05) compared to the others. The RC₅₀ and RC₉₀ values were 0,267 g/mL and 0,984 g/mL, respectively. The growing demand for botanical insecticides highlights L. grata essential oil as a promising alternative. This study demonstrated its high dose-dependent efficacy against C. megacephala, with significant adult and larval mortality and repellency, in addition to drastically inhibiting adult emergence. Its composition rich in Carvacrol and Thymol, acting synergistically, suggests multiple neurotoxic mechanisms of action, including acetylcholinesterase inhibition and modulation of GABAergic and octopaminergic receptors, as well as morphological alterations. These findings reinforce the potential of L. grata oil as a natural and effective solution for the control of this medically important fly species.Master Thesis Do ambiente ao hospedeiro: resistência a antifúngicos em leveduras em uma perspectiva de saúde única(Universidade Federal do Rio Grande do Norte, 2025-03-13) Silva, Lorena Souza; Bastos, Rafael Wesley; Schinaider, Kássia Jéssica Galdino da Silva; https://orcid.org/0000-0001-7038-6306; http://lattes.cnpq.br/9304612925767591; https://orcid.org/0000-0001-6781-9617; http://lattes.cnpq.br/3333946080391361; Silva, Danielle Letícia da; Santos, Julliana Ribeiro Alves dosResistance to antifungals has been increasing in some groups of fungi that cause invasive mycoses. Typically, the selection of resistance occurs following previous treatment with antifungals. However, there have been reports of infections caused by fungi that are already resistant, without any prior exposure to antifungals. This finding raises the hypothesis that the process of acquiring resistance may occur in the environment, possibly selected by antimicrobials with antifungal effects, such as environmental fungicides and hospital disinfectants. Thus, the aim of this study was to isolate, identify, and determine the resistance profile to clinical and environmental antifungals of medically important yeasts recovered from humans, animals (birds and pigs), and the environment. The yeasts were isolated from different sources and identified by mass spectrometry (MALDI-TOF MS). A total of 135 isolates were identified, with a prevalence of the following genera: (i) Candida (101; 74.8%), (ii) Kodamaea (17; 12.6%), (iii) Cryptococcus (7; 5.2%), and (iv) Trichosporon (5; 3.6%). After identification, the sensitivity profile of the isolates was determined using the Minimum Inhibitory Concentration (MIC) test by the broth microdilution method, employing clinical antifungals, environmental antifungals, and hospital disinfectants. Overall, the Candida genus exhibited a 13.8% resistance rate to clinical antifungals. The highest resistance was attributed to Micafungin (12.87%) and occurred in C. glabrata. Four multi-resistant isolates to Amphotericin B and Micafungin were also found, along with one isolate displaying multi-resistance to Fluconazole and Amphotericin B. The highest efficacy among the environmental antifungals was attributed to Tebuconazole, inhibiting 77% of the isolates. One isolate exhibiting resistance to both Fluconazole and Tebuconazole was identified, in addition to demonstrating high MIC values for hospital disinfectants. In summary, this study provides data on antifungal resistance in yeasts collected from various surrounding environments in the State of Rio Grande do Norte (RN), contributing to the understanding of the multifactorial relationship involved in the emergence of resistant yeast isolates of clinical importance.Master Thesis MPOX: aspectos epidemiológicos no estado do Rio Grande do Norte(Universidade Federal do Rio Grande do Norte, 2025-03-25) Lopes, Ximenya Glauce da Cunha Freire; Fernandes, José Veríssimo; Araújo, Joselio Maria Galvão de; https://orcid.org/0000-0002-5169-6496; http://lattes.cnpq.br/7078820975978056; http://lattes.cnpq.br/2920818609746057; Aloise, Debora de Almeida; Fernandes, Thales Allyrio Araújo de MedeirosMonkeypox is a zoonosis of viral etiology, caused by Monkeypox virus (MPXV), classified in the Poxviridae family, Orthopoxvirus genus, whose natural reservoir has not yet been identified. In 2022, MPXV spread to several countries around the world, affecting thousands of people. The World Health Organization declared a Public Health Emergency of International Concern and recommended the name mpox to replace monkeypox. In Brazil, the first case of the disease was confirmed in June 2022. The following month, mpox was confirmed in Rio Grande do Norte (RN). This study aims to analyze epidemiological aspects of mpox. This is a retrospective, descriptive study based on secondary data obtained from the REDCap platform and the e-SUS Sinan of the State Secretariat of Public Health of RN, referring to the period from 2022 to 2024. A total of 140 cases confirmed in the laboratory by the MPX PCR method were included. The analysis of the notification forms revealed the following epidemiological profile: highest incidence in August 2022 (35.0%; n=49); affecting Brazilians in the age group of 30 to 39 years (33.6%; n=47); male (86.4%; n=121); cisgender man (72.1%; n=101); homosexual (45.0%; n=63); brown skin color (44.3%; n=62); with completed higher education (36.4%; n=51); resident in the capital (68.6%; n=96); without immunosuppression (75.7%; n=106); without HIV (65.7%; n=92); who had sexual relations with men (54.3%; n=76). The form of transmission was not identified (42.1%; n=59). The most frequent signs and symptoms were: rash (86.4%; n=121), asthenia (83.6%; n=117), fever (61.4%; n=86), headache (49.3%; n=69), myalgia (35.7%; n=50), genital lesion (31.4%; n=44) and sore throat (30.7%; n=43). The majority did not require hospitalization (95.7%; n=134) or antiviral treatment (70.0%; n=98), and there were no deaths (0.0%; n=0). Possible risk factors were identified as: male gender, young adult, with high levels of education, and possible risk groups as young male individuals who have sex with men. The results of this study are similar to those of other studies and may help implement more effective policies for prevention and early diagnosis of the disease, reducing its impact on the population.Master Thesis Efeito atenuante do análogo sintético N-metil do alcaloide caulerpina no processo inflamatório em modelos murinos de inflamação(Universidade Federal do Rio Grande do Norte, 2025-03-14) Assunção, Adailson de Souza; Souto, Janeusa Trindade de; Souza, Cássio Ricardo de Medeiros; http://lattes.cnpq.br/6501426772186111; http://lattes.cnpq.br/7305814843923249; Brandão, Deysiane Oliveira; Nascimento, George João Ferreira doInflammation is a response of the body to different types of injuries, aiming to repair damaged tissues and eliminate dead cells Caulerpine is an alkaloid extracted from the marine algae Caulerpa racemosa with anti-inflammatory properties. Through structural modifications in the indole core and the ester group of classic caulerpine (CLPc), the N-methyl analog (CLPNmt) was generated, improving its solubility and lipophilicity. Thus, the present study aimed to evaluate the anti-inflammatory action of the CLPNmt analog in different murine models of acute inflammation, comparing it with CLPc and dexamethasone. Initially, a peritonitis model was conducted, where male Swiss mice were treated orally with CLPc (2 mg/kg), CLPNmt (4, 2, and 1 mg/kg), and intraperitoneally with dexamethasone (1 mg/kg). One hour later, they received zymosan (40 mg/kg) intraperitoneally. After 24 hours, the mice were euthanized, the peritoneal lavage was collected and centrifuged, and the total and differential leukocyte counts were determined. The supernatant was used for the quantification of IL-1β, IL-6, and TNF-α by ELISA. For the ear edema model, Swiss mice were treated with CLPNmt (2 mg/kg) and the other previously mentioned treatments, followed by the topical application of xylene (40 μL) on the right ears. One hour after treatment, the left and right ears were removed and weighed on a precision balance to determine the percentage of edema inhibition. The ears were then preserved in PBS/10% formalin for histological analysis. In the acute lung injury (ALI) model, the animals were treated orally with CLPc or CLPNmt (2 mg/kg) or intraperitoneally with dexamethasone (1 mg/kg). One hour later, the animals received 50 μL of LPS (100 μg/kg) intranasally. After 24 hours, the mice were euthanized, and the bronchoalveolar lavage (BAL) was collected and centrifuged. The cell pellet was used for total and differential leukocyte counts, while the supernatant was used for the quantification of inflammatory cytokines by ELISA and nitrite measurement using the Griess reaction. Lung samples were processed for histological analysis and RNA extraction to evaluate the quantitative expression of TNF-α by real-time polymerase chain reaction (qPCR). The results showed that CLPNmt treatment effectively reduced cell migration and IL-6 secretion in the peritoneal cavity, with the 2 mg/kg dose being the most efficient, which was then used as the standard dose in subsequent experiments. Moreover, CLPNmt significantly inhibited edema formation in the xyleneinduced model, similar to CLPc and dexamethasone. It also inhibited leukocyte recruitment to the pulmonary cavity, reduced IL-1β, IL-6, TNF-α, IFN-γ, and nitrite levels in BAL, and decreased lung damage in the ALI model. Therefore, the methylation of CLP maintained its anti-inflammatory potential, similar to what was observed for CLPc and compared to dexamethasone, making this analog a potential pharmacological target.Master Thesis Avaliação da infecção por Trypanosoma cruzi em triatomíneos em municípios considerados de alto risco de transmissão no Rio Grande do Norte, Brasil(Universidade Federal do Rio Grande do Norte, 2025-02-20) Silva, Odair José Queiroz da; Câmara, Antonia Cláudia Jácome da; Silva, Andressa Noronha Barbosa da; https://orcid.org/0000-0001-7337-9320; http://lattes.cnpq.br/5445255186647578; https://orcid.org/0009-0004-9161-1081; http://lattes.cnpq.br/5721162971304714; Vieira, Thallyta Maria; Guedes, Paulo Marcos da MattaThe state of Rio Grande do Norte (RN) is endemic for Chagas disease, with 36 municipalities at high risk of Trypanosoma cruzi transmission. The aim of this study was to assess the occurrence of T. cruzi infected triatomines domiciliary units (UDs) in municipalities at high risk of the parasite transmission in RN, as well as the species diversity in the wild environment. Triatomines were collected in DUs and wild environments, identified, and their intestinal content analyzed by using direct examination, xenoculture, and kDNA PCR for parasite detection. A total of 22 DUs were investigated, 14 in São Tomé and six in Sítio Novo, with the presence of triatomines recorded in 21.4% (3/14) and 16.7% (1/6), respectively. The municipality São Tomé showed a high percentage of infected triatomines, corresponding to 14.2%. In the DUs, 40 triatomines were captured, and the only species identified was Triatoma brasiliensis in both São Tomé and Sítio Novo. The natural infection rate for T. cruzi was 7.5%, with the highest rate in T. brasiliensis (8.8%). In the wild environment, the highest species diversity was found in the ESEC-Seridó, where specimens of T. brasiliensis, Triatoma pseudomaculata, Panstrongylus lutzi, and Triatoma sp. were captured. Triatoma brasiliensis was the most frequently captured species in both ESEC-Seridó and Sítio Novo. These data highlight the importance of continuous surveillance and control in high-risk municipalities to prevent T. cruzi transmission to humans and animals.Master Thesis Prevalência de Staphylococcus aureus e Staphylococcus aureus resistente à meticilina no meio ambiente bucal de pessoas idosas domiciliadas e acamadas, e fatores associados à essa colonização(Universidade Federal do Rio Grande do Norte, 2025-03-21) Tavares, Isabelle Lisiany de Lima; Melo, Maria Celeste Nunes de; https://orcid.org/0000-0002-9826-4981; http://lattes.cnpq.br/0580551464788795; https://orcid.org/0000-0001-8685-3327; http://lattes.cnpq.br/2268942016005418; Brandão, Deysiane Oliveira; Almeida, Gilmara Celli Maia deThe elderly population is the fastest growing demographic in the world. As a consequence, there is an increase in the number of elderly people living at home or even bedridden, withvarying degrees of dependence. With aging, the immune system becomes less efficient, generating systemic impairments in the elderly, who become more vulnerable to possiblebacterial infections by multidrug-resistant pathogens. The objective of this studywastoevaluate the prevalence of Staphylococcus aureus and Methicillin-resistant Staphylococcusaureus (MRSA) colonizing the oral environment of elderly people living at home, whetherbedridden or not, as well as to evaluate factors associated with this colonization. Sampleswere collected from the oral environment of 263 elderly people from August to November2023, in the city of Natal/RN. The samples were collected with the help of swabs, whichwereplaced in saline solution and sent to the research laboratory. The samples were inoculatedinBHI (Brain Heart Infusion Broth) enrichment broth and after incubation were seededintheselective culture medium mannitol salt agar. Colonies suggestive of Staphylococcus aureuswere reisolated with subsequent identification through conventional laboratory tests andmassspectrometry (MALDI-TOF). The identification of the MRSA strain was performedbythedisk diffusion method, using the antimicrobial cefoxitin. The same technique was usedtoassess the susceptibility profile to other antimicrobials. Data related to sociodemographicfactors and access, care, and general and oral health conditions were collected throughtheapplication of a questionnaire. The prevalence of elderly individuals colonized by S. aureuswas 13.3% (n=35) and for MRSA it was 1.5% (n=4). The MRSA strains were resistant topenicillin, erythromycin, and clindamycin. After performing the multivariate analysis, thevariables that had a significant association with the presence of S. aureus were self-perceivedgeneral health (p=0.005) and difficulty in eating (p=0.006). Poor general health and difficultyin eating due to pain were the factors that contributed to colonization by S. aureus. Thepresence of S. aureus, especially the MRSA lineage, colonizing elderly people may represent a health risk to this population, especially due to their greater immunological vulnerability.Master Thesis Efeito da azitromicina no ciclo de desenvolvimento de Chrysomya megacephala (Diptera: calliphoridae)(Universidade Federal do Rio Grande do Norte, 2024-05-21) Diógenes, Mahara Gabrielle Barbosa; Gama, Renata Antonaci; Motta Neto, Renato; https://orcid.org/0000-0002-8026-6022; http://lattes.cnpq.br/0179756405650744; http://lattes.cnpq.br/7755382632811974; Bastos, Rafael Wesley; Barbosa, Taciano de Moura; Inácio, Cássio Lázaro SilvaIntroduction: Due to the pandemic scenario spanning from 2020 through 2022, the antibiotic azithromycin was extensively utilized as part of the "COVID kit" during the COVID-19 pandemic. This study aims to analyze the effects of azithromycin on biometric aspects of Chrysomya megacephala, including mass gain, size, and developmental cycle duration. Methods: Two hundred eggs per treatment were used in assays, maintained in an insectary and reared in plastic containers with raw minced meat supplemented with azithromycin at three concentrations: D1 (30μl), D2 (60μl), and D3 (120μl). Monitoring was conducted at the Insect and Vector Laboratory (LIVe) every six hours, assessing emergence inhibition, duration of each developmental stage, and measurements of mass and size. Results and Discussion: Individuals exposed to azithromycin showed increased mass during larval periods, up to double that of the control, and larger size. Regarding emergence inhibition, D2 and D3 treatments exhibited lower rates, at 7.56% and 27.73%, respectively. Group D1 recorded the highest inhibition rate at 64.71%. The developmental cycle duration for azithromycin-treated groups showed a 6-hour advancement in the larval stage compared to the control, with a similar trend observed in the pupal stage. Emergence also occurred 24 hours earlier than the control group across all concentrations. Conclusion: Bioassays demonstrate that azithromycin affected biometric parameters of C. megacephala, influencing mass gain and size during immature stages, as well as altering the total developmental cycle duration and emergence inhibition. These findings highlight the ecological implications of azithromycin use, suggesting potential impacts on insect populations and ecological processes in environments where such antibiotics may be introduced.Master Thesis Avaliação da atividade inseticida do fluralaner (Exzolt®) administrado em galinhas contra triatomíneos(Universidade Federal do Rio Grande do Norte, 2024-03-07) Pereira, Luanderson Cardoso; Guedes, Paulo Marcos da Matta; http://lattes.cnpq.br/5445410844075357; http://lattes.cnpq.br/0214566514443012; Silva, Andressa Noronha Barbosa da; Sousa, Rita de Cássia Moreira deTriatoma infestans, Triatoma brasiliensis, Triatoma pseudomaculata and Rhodnius prolixus are vectors of Trypanosoma cruzi, the etiological agent of Chagas disease, and chickens are important food sources for these insects in anthropogenic environments. The aim of this study was to evaluate the insecticidal activity of fluralaner (Exzolt®) administered to chickens against triatomines (R. prolixus, T. infestans, T. brasiliensis and T. pseudomaculata). Twelve mixed-breed chickens (Gallus gallus domesticus) were randomized, according to weight, into three groups: Group 1 - untreated control (n=4); Group 2 - single dose of 0.5mg/kg of fluralaner (Exzolt®) (n=4); and Group 3 - two doses of 0.5mg/kg of fluralaner (Exzolt®) (n=4). Subsequently, they were subjected to blood feeding using nymphs (n = 10) of 3rd, 4th and 5th instars of T. infestans, T. brasiliensis, T. pseudomaculata and R. prolixus before treatment and 1, 7, 14, 21, 28, 35 and 56 days after treatment. After blood feeding, the feeding efficiency and mortality of triatomine nymphs were determined. The results demonstrate greater feeding success for R. prolixus, followed by T. infestans, T. brasiliensis and T. pseudomaculata, respectively. Treatment of chickens with fluralaner does not affect the blood feeding rate of triatomines. Treatment with two doses of fluralaner showed greater insecticidal activity for R. prolixus, T. infestans and T. brasiliensis, compared to treatment with a single dose. Similar insecticidal efficacy was observed for T. pseudomaculata using single- and double-dose fluralaner treatments. The insecticidal activity of fluralaner (Exzolt®) against triatomines was observed up to 21 and 28 days after single- and double-dose treatment, respectively. Our results demonstrate that treatment of chickens with fluralaner (Exzolt®) induces insecticidal activity against triatomines up to 28 days after treatment and could be used as a control measure for Chagas disease in endemic areas.