RESUMO
Chagas disease (CD), caused by the parasite Trypanosoma cruzi, is a neglected tropical disease with life-threatening implications. In this study, we conducted a seroepidemiological survey to determine the prevalence and clinical profiles of CD in 217 individuals from an impoverished rural community in Southern Bahia, Brazil. The overall prevalence of CD in the studied community was 0.92%, detected through latent class analysis (LCA). Two individuals tested positive for anti-T. cruzi IgG, both being male farmers. One case was a 22-year-old man born in Camamu, with no evidence of congenital transmission, suggesting other routes of transmission such as vector-borne transmission due to migratory activities. The other case was a 69-year-old man born in São Felipe, who had lived in an adobe/brick house and had a pacemaker due to cardiac involvement caused by CD. The prevalence in this community was lower than expected, given the socioeconomic conditions and environmental factors that contribute to T. cruzi transmission. This could be attributed to the implementation of preventive measures and vector control programs by the Brazilian Government. However, continuous monitoring and surveillance are essential to sustain control efforts and detect any potential re-emergence of the disease. While the overall prevalence was low, the detection of positive cases underscores the need for continued surveillance and control measures in vulnerable populations, such as rural communities. Active surveillance, early diagnosis, and timely treatment are crucial in preventing disease progression and complications, thereby enhancing the effectiveness of screening and treatment programs.
RESUMO
Introduction: Individuals infected with the human T-lymphotropic virus type 1 (HTLV-1) may present severe and disseminated forms of Strongyloides stercoralis infection with low therapeutic response. Objective: To investigate the S. stercoralis infection and the seroprevalence of IgG anti-S. stercoralis antibodies in individuals infected with HTLV-1 attending the Reference Center for HTLV-1 (CHTLV) in Salvador, Bahia, Brazil. Materials and methods: We conducted a cross-sectional study in 178 HTLV-1-infected individuals treated at the HTLV specialized center between January, 2014, and December, 2018. The parasitological diagnosis of S. stercoralis was performed using the Hoffman, Pons and Janer, agar plate culture, and Baermann-Morais methods. The IgG anti-S. stercoralis detection was performed using an in house enzyme-linked immunosorbent assay (ELISA). The HTLV-1 infection was diagnosed using a commercial ELISA and confirmed by Western blot. Results: The frequency of S. stercoralis infection was 3.4% (6/178). Individuals infected with S . stercoralis from rural areas (50.0%; 3/6) also showed S. stercoralis hyperinfection (>3,000 larvae/gram of feces). The frequency of circulating anti-S. stercoralis IgG antibodies was 20.8% (37/178). Conclusions: HTLV-1-infected people living in precarious sanitary conditions are more prone to develop severe forms of S. stercoralis infection. Considering the high susceptibility and unfavorable outcome of the infection in these individuals, the serological diagnosis for S. stercoralis should be considered when providing treatment.
Introducción. Los individuos infectados por el virus linfotrópico T humano tipo 1 (HTLV-1) pueden presentar formas graves y diseminadas de infestación por Strongyloides stercoralis con poca mejoría terapéutica. Objetivo. Investigar la infestación por S. stercoralis y la seroprevalencia de IgG anti-S. stercoralis en individuos infectados por HTLV-1 atendidos en el Centro de Referencia para HTLV-1 (CHTLV), en Salvador, Bahía, Brasil. Materiales y métodos. Se hizo un estudio transversal con 178 individuos infectados por HTLV-1 atendidos en el centro especializado de HTLV entre enero de 2014 y diciembre de 2018. El diagnóstico parasitológico de S. stercoralis se hizo mediante los métodos de Hoffman, Pons y Janer, cultivo en placa de agar y Baermann-Morais. Para la detección de IgG anti-S. stercoralis, se utilizó una prueba casera de inmunoabsorción ligada a enzimas (ELISA). La infección por HTLV-1 se diagnosticó usando un ELISA comercial y se confirmó mediante Western blot. Resultados. La frecuencia de infestación por S. stercoralis fue del 3,4 % (6/178). Además, los individuos infestados por S. stercoralis provenientes de la zona rural (50,0 %; 3/6) también mostraron hiperinfestación por S. stercoralis (>3.000 larvas/gramo de heces). La frecuencia de anticuerpos IgG anti-S. stercoralis fue del 20,8 % (37/178). Conclusiones. Las personas infectadas por HTLV-1 que viven en condiciones sanitarias precarias son más propensas a desarrollar formas graves de infestación por S. stercoralis. Teniendo en cuenta la gran vulnerabilidad y el resultado desfavorable de la infección en estos individuos, se debe considerar el diagnóstico serológico de S. stercoralis para administrar el tratamiento
