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.

Does In-Person Visiting Affect the Number of COVID-19 Cases in Prisons?

Even with the current advances that have been made in regard to COVID-19, such as a better understanding of the disease and the steady growth in the number of vaccinated individuals, it remains a challenge for humanity. Dealing with the disease in prison settings has been particularly difficult. This study sought to discover whether in-person visiting affected the number of cases of SARS-CoV-2 infection in the penitentiaries in the state of Sergipe (Brazil). We conducted a two-phase study (when visiting was suspended and after it recommenced) in seven penitentiaries in Sergipe using immunochromatography and nasopharyngeal swab testing to evaluate whether visiting affects the number of COVID-19 cases. In the first phase (n = 778), 57.6% of inmates reported risk factors and 32.5% were positive for COVID-19 (18.9% IgM, 24.2% IgG, 1% antigen). In the second phase, 19.6% tested positive (13.9% IgM, 7.9% IgG, 0.2% antigen). The occurrence of positive cases of COVID-19 and positive results (IgM and IgG) were significantly higher in the first phase. In the second phase, 56.7% of inmates had received visits and 18.7% were positive for COVID-19 (14% IgM, 7% IgG). Among those who had not received visits, 20.9% tested positive (13.8% IgM, 9.2% IgG, 0.5% antigen). There was no significant difference in positive cases/results between inmates that had and had not received visits. These findings suggest that, under the conditions assessed, visiting does not seem to affect the number of COVID-19 cases in prisons and reinforces the importance of sanitary measures to control dissemination.

Seroprevalence of SARS-CoV-2 antibodies in the poorest region of Brazil: results from a population-based study.

Population-based seroprevalence studies on coronavirus disease 2019 (COVID-19) in low- and middle-income countries are lacking. We investigated the seroprevalence of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) antibodies in Sergipe state, Northeast Brazil, using rapid IgM-IgG antibody test and fluorescence immunoassay. The seroprevalence was 9.3% (95% CI 8.5-10.1), 10.2% (95% CI 9.2-11.3) for women and 7.9% (IC 95% 6.8-9.1) for men (P = 0.004). We found a decline in the prevalence of SARS-CoV-2 antibodies according to age, but the differences were not statistically significant: 0-19 years (9.9%; 95% CI 7.8-12.5), 20-59 years (9.3%; 95% CI 8.4-10.3) and ≥60 years (9.0%; 95% CI 7.5-10.8) (P = 0.517). The metropolitan area had a higher seroprevalence (11.7%, 95% CI 10.3-13.2) than outside municipalities (8.0%, 95% CI 7.2-8.9) (P < 0.001). These findings highlight the importance of serosurveillance to estimate the real impact of the COVID-19 outbreak and thereby provide data to better understand the spread of the virus, as well as providing information to guide stay-at-home measures and other policies. In addition, these results may be useful as basic data to follow the progress of COVID-19 outbreak as social restriction initiatives start to be relaxed in Brazil.

Factors Associated with Mortality among Hospitalized Patients with COVID-19: A Retrospective Cohort Study.

Information on the risk factors for COVID-19 mortality in low- and middle-income countries is still scarce. In this retrospective cohort study, we analyzed the factors associated with COVID-19 mortality in hospitalized patients in a poor area of Brazil. Logistic regression was used to identify factors independently associated with mortality, including gender, age, and the presence of underlying medical conditions. A total of 1,207 patients were included in the analysis, and a 1.5-fold increase in COVID-19 mortality was found among patients aged > 65 years with hypertension and diabetes (odds ratio [OR]: 1.50, 95% CI: 1.02-2.19). Moreover, infectious disease (OR: 4.31, 95% CI: 1.39-13.39), kidney disease (OR: 2.59, 95% CI: 1.27-5.27), and heart disease (OR: 2.00, 95% CI: 1.31-3.04) were also predictive for COVID-19 in-hospital death. This large cohort provides important data on potential factors associated with COVID-19 mortality in Brazil.