Dynamics of SARS-CoV-2 seroprevalence during the first year of the COVID-19 pandemic in the Northeast region of Brazil.

In this household-based seroepidemiological survey, we analyzed the dynamics of SARS-CoV-2 seroprevalence during the first year of the COVID-19 pandemic in Sergipe State, Northeast Brazil, the poorest region of the country. A total of 16,547 individuals were tested using a rapid IgM-IgG antibody test and fluorescence immunoassay (FIA). Seroprevalence rates were presented according to age, sex, and geographic region. A comparative analysis was performed between the results obtained in July 2020 (peak of the first wave), August - November 2020 (end of the first wave), and February - March 2021 (beginning of the second wave). Seroprevalence rates in the three phases were estimated at 9.3% (95% CI 8.5-10.1), 12.0% (95% CI 11.2-12.9) and 15.4% (95% CI 14.5-16.4). At the end of the first wave, there was a rise in seroprevalence in the countryside (p < 0.001). At the beginning of the second wave, we found an increase in seroprevalence among women (p < 0.001), adults aged 20 to 59 years (p < 0.001), and the elderly (p < 0.001). In this phase, we found an increase in estimates both in metropolitan areas and in the countryside (p < 0.001). This study showed an increase in SARS-CoV-2 seroprevalence over the first year of the pandemic, with approximately one in six people having anti-SARS-CoV-2 antibodies at the beginning of the second wave of COVID-19. Furthermore, our results suggest a rapid spread of COVID-19 from metropolitan areas to the countryside during the first months of the pandemic.

Seroprevalence of SARS-CoV-2 antibodies in radio and television workers.

We investigated the seroprevalence of SARS-CoV-2 antibodies in individuals working in radio and television stations (TV) in Sergipe state, Northeast Brazil. This cross-sectional study was conducted from December 1 to December 20, 2020, a period which was considered as the beginning of the second wave of COVID-19 in the state. One hundred and thirteen professionals from the three largest media companies in the state were included in this study. Venous blood was collected using venipuncture and a fluorescence immunoassay for qualitative detection and differentiation of IgM and IgG antibodies against SARS-CoV-2 was performed. Twenty-eight media workers had detectable levels of SARS-CoV-2 antibodies (11 IgM+, 6 IgM+/ IgG+, and 11 IgG+) and the estimated seroprevalence was 24.8 % (95 % CI 17.7 - 33.5). Our findings showed a high seroprevalence of SARS-CoV-2 antibodies in radio and TV workers during the second wave of COVID-19 in Brazil.

Functional and concurrent training do not impair immune function and improve functional fitness in postmenopausal women: A randomized controlled trial.

PURPOSE: To evaluate the effects of functional and concurrent training on immune function and functional fitness in postmenopausal women. MATERIALS AND METHODS: A randomized controlled trial was performed on 108 women aged 60 or older who were randomly assigned among the groups: control group (CG: n = 40; 63.88 ± 3.64 years); functional training (FT: n = 32; 63.88 ± 3.79 years); and concurrent training (CT: n = 36; 64.83 ± 4.00 years). Immune function was measured by the expression of the T-lymphocyte function-related surface markers (CD28 and CD57). Functional fitness was assessed using physical tests similar to daily activities, i.e., five times sit to stand, timed up and go, and gallon-jug shelf-transfer. RESULTS: Regarding immune function, there was only a time effect, without between-group differences. Specifically, FT and CT show a reduction and increase in CD4+ and CD8+ T cells, respectively, without impairment in the subpopulations analyzed, while CG showed a reduction in naive T cells (CD8+CD28+). For functional fitness tests, there was a time × group interaction effect for all tests, the FT and CT were superior to the CG, with FT showing differences after the fourth week, while the CT showed this effect after the eighth week of intervention. CONCLUSION: FT and CT do not impair immune function and similarly improve functional fitness in postmenopausal women. CLINICAL TRIALS REGISTRY: RBR-2d56bt.