Estudos epidemiológicos sobre a Covid-19: hipótese enteral, aumento de mortes súbitas cardíacas, efeitos do isolamento e da imunização e estudo de correlação espacial com análise de séries temporais com ruptura de bayes e impacto causal para conclusões contrafatuais

Abstract

Introduction: The COVID-19 pandemic has had a profound impact on global public health, affecting multiple aspects of social and healthcare systems. This study investigates these impacts from four main perspectives: sudden cardiac deaths, basic sanitation, social isolation, and vaccination.Methods: Four distinct studies were conducted using advanced epidemiological and statistical approaches: An epidemiological, observational, and descriptive study, utilizing Bayesian models and counterfactual analysis to assess the pandemic’s impact on sudden cardiac deaths (SCD) in Brazil. A spatial correlation analysis explored the relationship between the quality of basic sanitation and COVID-19 mortality rates across all Brazilian municipalities. An assessment of the effects of social isolation in the state of São Paulo was conducted using paired t-tests, Bayesian breakpoint analysis, and causal impact analysis. A cross-sectional study in 18 countries employed the AMOC model and the "changepoint" package in R to estimate the number of deaths prevented by COVID-19 vaccination.Results: A significant increase in the monthly average of SCDs was observed during the pandemic, rising from 176.6 to 555.03 cases per month, resulting in an additional 12,522 cases over the pandemic period. Municipalities with poor basic sanitation showed higher rates of COVID-19 incidence and mortality, with high-mortality clusters identified mainly in the North and Northeast regions. The analysis of social isolation in São Paulo indicated that isolation measures, initially appearing ineffective, were influenced by latent variables such as vaccination, which significantly altered the outcomes. Vaccination proved highly effective in the 18 countries studied, reducing the average daily COVID-19 deaths from 2.53 to 0.54 per million, preventing approximately 2,886,869 deaths.Conclusions: The results highlight the direct influence of COVID-19 on cardiovascular mortality, the importance of basic sanitation in pandemic management, the complexity of social isolation effects, and the efficacy of vaccination campaigns. The implications are clear: public policies should focus on improving sanitation infrastructure and continuing vaccination efforts. Future research should consider latent variables and evaluate policies within distinct regional contexts.