Unravelling COVID-19 waves in Rio de Janeiro city: Qualitative insights from nonlinear dynamic analysis.

Since the COVID-19 pandemic was first reported in 2019, it has rapidly spread around the world. Many countries implemented several measures to try to control the virus spreading. The healthcare system and consequently the general quality of life population in the cities have all been significantly impacted by the Coronavirus pandemic. The different waves of contagious were responsible for the increase in the number of cases that, unfortunately, many times lead to death. In this paper, we aim to characterize the dynamics of the six waves of cases and deaths caused by COVID-19 in Rio de Janeiro city using techniques such as the Poincaré plot, approximate entropy, second-order difference plot, and central tendency measures. Our results reveal that by examining the structure and patterns of the time series, using a set of non-linear techniques we can gain a better understanding of the role of multiple waves of COVID-19, also, we can identify underlying dynamics of disease spreading and extract meaningful information about the dynamical behavior of epidemiological time series. Such findings can help to closely approximate the dynamics of virus spread and obtain a correlation between the different stages of the disease, allowing us to identify and categorize the stages due to different virus variants that are reflected in the time series.

Trends in suicide rates in Brazil from 1997 to 2015

Objectives: To analyze time trends of suicide rates in Brazil overall and in Brazilian states and compare the estimated suicide rates projected for 2020 with the World Health Organization (WHO) Mental Health Action Plan target. Methods: This was an ecological time-series study from 1997 to 2015, stratified by Brazilian states, specific age groups, and sex. Data were obtained from the Mortality Information System (Sistema de Informações sobre Mortalidade [SIM]) of the Brazilian Ministry of Health. Polynomial regression models were used to analyze the trends in suicide rates and to project suicide rates for 2020. Results: Considering 224 units of analysis, 21 (9.4%) showed a decreasing trend, 108 (48.2%) were stable, and 95 (42.4%) showed an increasing trend. Thus, 67% of units of analysis will not meet the WHO target in 2020. Mean suicide rates were higher in males than in females. People aged 60 years and older presented the highest suicide rates, while 84.7% of total deaths by suicide occurred among 15-to-59-year-olds. Conclusion: Overall, 90.6% of units of analysis had a stable or increasing trend in suicide rates from 1997 to 2015. If these trends remain, most of Brazil will fail to achieve the WHO-recommended reduction in suicide rates by 2020.

Trends in suicide rates in Brazil from 1997 to 2015.

OBJECTIVES: To analyze time trends of suicide rates in Brazil overall and in Brazilian states and compare the estimated suicide rates projected for 2020 with the World Health Organization (WHO) Mental Health Action Plan target. METHODS: This was an ecological time-series study from 1997 to 2015, stratified by Brazilian states, specific age groups, and sex. Data were obtained from the Mortality Information System (Sistema de Informações sobre Mortalidade [SIM]) of the Brazilian Ministry of Health. Polynomial regression models were used to analyze the trends in suicide rates and to project suicide rates for 2020. RESULTS: Considering 224 units of analysis, 21 (9.4%) showed a decreasing trend, 108 (48.2%) were stable, and 95 (42.4%) showed an increasing trend. Thus, 67% of units of analysis will not meet the WHO target in 2020. Mean suicide rates were higher in males than in females. People aged 60 years and older presented the highest suicide rates, while 84.7% of total deaths by suicide occurred among 15-to-59-year-olds. CONCLUSION: Overall, 90.6% of units of analysis had a stable or increasing trend in suicide rates from 1997 to 2015. If these trends remain, most of Brazil will fail to achieve the WHO-recommended reduction in suicide rates by 2020.