Seroprevalence of Dengue, Chikungunya, and Zika viruses antibodies in a cohort of asymptomatic pregnant women in a low-income region of Minas Gerais, Brazil, 2018-2019.

Dengue, Chikungunya, and Zika viruses are arthropod-borne viruses (arboviruses) that infect millions of individuals in tropical and subtropical regions. In the Americas, arboviruses represent a major public health problem, especially among vulnerable groups such as the elderly, children, and pregnant women. In this study, the seroprevalence of IgM or IgG against these arboviruses in pregnant, young women in the city of Diamantina, Minas Gerais, Brazil, and the influence of sociodemographic factors on the incidence/prevalence of infection in this group were investigated. A cross-sectional investigation was conducted on a total of 135 pregnant women for Dengue and Chikungunya IgM and 88 pregnant women for Zika IgG. Dengue IgM was found on the serum of twenty participants (14.8%) and only one woman (0.7%) tested positive for Chikungunya IgM. Zika IgG was found in three (3.4%) participants and 2 women who tested positive for Zika virus were also positive for Dengue virus IgM. Although the arboviruses seroprevalence was higher frequency among young (20-25 years old), brown and high school women, with a monthly income of 1-3 minimum wages, no association between these sociodemographic factors and arboviruses seroprevalence was found.

Detection of SARS-CoV-2 genome on inanimate surfaces in COVID-19 intensive care units and emergency care cohort.

INTRODUCTION: Understanding the different transmission routes of SARS-CoV-2 is crucial in planning effective interventions in healthcare institutions. This study aimed to evaluate the presence of SARS-Cov-2 genome on inanimate surfaces in COVID-19 intensive care unit and emergency care cohorts. METHODS: This is a prospective cross-sectional study. Samples of the environmental surface of objects and furniture were collected between July 15 and October 15, 2020, at COVID-19 intensive and emergency care units. The presence of SARS-CoV-2 genome was determined by quantitative RT-qPCR. The positivity rate for SARS-Cov-2 genome is presented as the arithmetic mean of the sum of the values obtained in each collection. Values of 1.0, 0.5, and 0.0 were assigned for positive, indeterminate, and negative events, respectively. RESULTS: In the intensive care unit, 86% of samples collected at the stethoscope and bed rail surfaces were positive. In the emergency care unit, 43% of bathroom tap, bed rails, and bedside table samples were positive. SARS-CoV-2 genome was not detected at the computer mouse and keyboard. At the emergency care unit, 14.3% of the samples from the collection room armchair were positive. CONCLUSIONS: SARS-CoV-2 genome can be found at the environmental surface of objects and furniture at COVID-19 care units. They can represent a potential source of indirect transmission pathway for COVID-19, especially within health service institutions.

Antiviral effect of silymarin against Zika virus in vitro.

Zika virus (ZIKV) epidemic and its association with severe neurological syndromes have raised worldwide concern. Despite the great clinical relevance of this infection, no vaccine or specific treatment is available and the search for antiviral compounds against ZIKV is extremely necessary. Several natural compounds, such as silymarin, exhibit antioxidant, hepatoprotective, and antiviral properties; however, the antiviral potential of this compound remains partially investigated. Therefore, the objective of this study was to evaluate in vitro the antiviral activity of silymarin against ZIKV infection. Global antiviral activity, dose-dependent, plaque reduction, and time-of-drug-addition assays were used to determine the anti-ZIKV activity of silymarin. Additionally, to start characterizing the mechanisms of action we determined whether silymarin could have a virucidal effect and inhibit viral adsorption and penetration stages. Regarding its global antiviral activity, silymarin showed significant inhibition of ZIKV infection, protecting cells infected with EC50 equal to 34.17µg/mL, with a selectivity index greater than 17 and 4x greater than that of the positive control (ribavirin). Its greatest efficiency was achieved at 125µg/mL, whose cell viability did not differ from the control without infection and treatment. Furthermore, treatment with silymarin reduced viral load by up to two logs (> 90%) concerning viral control, when evaluating virucidal activity and the precocious times of infection. Thus, our results set to show the promising anti-ZIKV activity of silymarin, which does not seem to have a single inhibition mechanism, acting at different times of infection, and still has the advantage of silymarin be a phytotherapy already available on the market.