Biologia molecular, características clínicas e epidemiologia da infecção pelo vírus Chikungunya em uma coorte de pacientes brasileiro

Abstract

Chikungunya virus (CHIKV) is primarily transmitted by infected Aedes spp. mosquitoes. Clinical manifestations include fever, myalgia, arthritis, and arthrosis. The global increase in arboviral infections has led to 350,000 Chikungunya cases, with Brazil, Paraguay, Argentina, and Bolivia reporting the highest numbers in 2024. Objective: To evaluate the epidemiological and clinical characteristics, and to determine the viral load in individuals testing positive for Chikungunya, in a laboratory diagnostic service in Juiz de Fora/Minas Gerais. Material and methods: Viral RNA (ribonucleic acid) was extracted from serum samples using the KingFisher equipment (ThermoFisher Scientific/Sweden), and RT-qPCR testing was performed to detect Dengue, Zika, and Chikungunya (ThermoFisher Scientific/Sweden). CHIK-positive cases were included, and viral load was quantified by RT-qPCR. Clinical and epidemiological data were collected from medical records. Results: Of 2,807 samples tested, 49 were positive for CHIKV, with most cases occurring in women (53.06%), aged 60–70 years (23.08%). The most common symptoms were myalgia (81.63%) and fever (75.51%). Hypertension was the most common comorbidity (10.20%). Eight samples also tested positive for Dengue virus. Higher viral loads were observed in children/young adults. Conclusion: Higher viral loads were observed in children/young adults, although they were not the most affected. Co-detection between Chikungunya and Dengue viruses warrants further research and surveillance. Molecular techniques like RT-qPCR are crucial for accurate diagnosis.