Covid-19: temporal evolution and immunization in the three epidemiological waves, Brazil, 2020-2022.

OBJECTIVE: Describe the temporal evolution of morbimortality due to Covid-19 and vaccination coverage during the health emergency in Brazil. METHODS: Number of cases and deaths due to Covid-19 were extracted from the public panel of the Brazilian Ministry of Health, according to epidemiological week (EW) and geographic region. Data on vaccines and variants were obtained, respectively, from the Information System of the National Immunization Program and the Genomic Surveillance System of SARS-CoV-2. RESULTS: Three peaks of deaths characterized the evolution of the Covid-19 pandemic: in EW 30 of 2020, in the EW 14 of 2021 and in the EW six of 2022; three case waves, starting in the North and Northeast regions, with higher rates in the third wave, mainly in the South region. Vaccination started in the epidemiological week three of 2021, rapidly reaching most of the population, particularly in the Southeast and South regions, coinciding with a reduction exclusively in the mortality rate in the third wave. Only from the beginning of the second wave, when Gama was the dominant variant, 146,718 genomes were sequenced. From the last EW of 2021, with vaccination coverage already approaching 70%, the Omicron variant caused an avalanche of cases, but with fewer deaths. CONCLUSIONS: We noticed the presence of three waves of Covid-19, as well as the effect of immunization on the reduction of mortality in the second and third waves, attributed to the Delta and Omicron variants, respectively. However, the reduction of morbidity, which peaked in the third wave during the domination of the Omicron variant, remained the same. The national and centralized command of the pandemic confrontation did not occur; thus, public administrators took the lead in their territories. The overwhelming effect of the pandemic could have been minimized, if there had been a coordinated participation of three spheres of the Brazilian Unified Health System administration, in the joint governance of the pandemic fight.

[Social vulnerability, survival, and hospital lethality by COVID-19 in patients aged 50 years and over: retrospective cohort of cases in Brazil in 2020 and 2021]. / Vulnerabilidade social, sobrevida e letalidade hospitalar pela COVID-19 em pacientes com 50 anos ou mais: coorte retrospectiva de casos no Brasil em 2020 e 2021.

The outcome of SARS-CoV-2 infection is not only associated with age and comorbidities but is also aggravated by social vulnerability. This study aims to analyze - according to social vulnerability - survival and hospital lethality by COVID-19 in the first 100 days from symptoms to death in individuals aged 50 years or older hospitalized in Brazil. This is a retrospective cohort from Epidemiological Week 11 of 2020 to week 33 of 2021. The Influenza Epidemiological Surveillance Information System (SIVEP-Gripe) provided clinical and epidemiological data. The Geographic Index of the Socioeconomic Context for Health and Social Studies (GeoSES) measured social vulnerability. The Kaplan-Meier curve and the adjusted proportional risk model by Cox were used for survival, with hazard ratio (HR) and 95% confidence intervals (95%CI). Among the 410,504 cases, overall lethality was of 42.2% in general and 51.4% in the most vulnerable. We found a higher lethality according to worse socioeconomic status in all categories by age group; the double is registered for 50-59 years. The adjusted Cox model showed a 32% increase in risk of death (HR = 1.32; 95%CI: 1.24-1.42). Moreover, men, older adults, black or indigenous adults, with multiple comorbidities, and subjected to invasive ventilation, have a higher risk of death after hospitalization. Intersectoral policy measures need to be targeted to alleviate the effects of the COVID-19 pandemic aggravated by social vulnerability.

O desfecho da infecção pelo SARS-CoV-2 não se associa apenas à idade e a comorbidades, mas também agrava-se por vulnerabilidade social. Este estudo tem como objetivo analisar, segundo vulnerabilidade social, a sobrevida e a letalidade hospitalar por COVID-19 para os primeiros 100 dias entre sintomas até o óbito em indivíduos de 50 anos ou mais hospitalizados no Brasil. Trata-se de uma coorte retrospectiva das Semanas Epidemiológicas 11, de 2020, a 33, de 2021. O Sistema de Informação de Vigilância Epidemiológica da Gripe (SIVEP-Gripe) forneceu dados clínico-epidemiológicos. O Índice Socioeconômico do Contexto Geográfico para Estudos em Saúde (GeoSES) mensurou vulnerabilidade social. Para sobrevida, utilizou-se a curva de Kaplan-Meier e o modelo ajustado de riscos proporcionais de Cox, com hazard ratio (HR) e intervalos de 95% de confiança (IC95%). Dentre os 410.504 casos, a letalidade geral foi de 42,2%, sendo 51,4% os indivíduos mais vulneráveis. Por faixa etária, registra-se a presença de maior letalidade para os piores status socioeconômicos em todas as categorias; para 50-59 anos, registra-se o dobro. O modelo ajustado de Cox mostrou aumento de 32% de risco para óbito (HR = 1,32; IC95%: 1,24-1,42). Ademais, homens, idosos, pretos ou indígenas, com múltiplas comorbidades e submetidos à ventilação invasiva apresentam maior risco de óbito após hospitalização. É necessário que medidas políticas intersetoriais sejam direcionadas para mitigar os efeitos da pandemia de COVID-19 agravados pela vulnerabilidade social.

El pronóstico de la infección por SARS-CoV-2 no sólo está asociado a la edad y a las comorbilidades, sino que también empeora por la vulnerabilidad social. El presente estudio tiene como objetivo analizar, según la vulnerabilidad social, la supervivencia y la letalidad hospitalaria por COVID-19 durante los primeros 100 días entre los síntomas hasta la muerte en individuos de 50 años o más hospitalizados en Brasil. Se trata de una cohorte retrospectiva desde la Semana Epidemiológica 11 de 2020 hasta la 33 de 2021. El Sistema de Información de Vigilancia Epidemiológica de la Gripe (SIVEP-Gripe) proporcionó datos clínico-epidemiológicos. El Índice Socioeconómico del Contexto Geográfico para los Estudios de Salud (GeoSES) midió la vulnerabilidad social. Para la supervivencia se utilizó la curva de Kaplan-Meier y el modelo ajustado de riesgos proporcionales de Cox, con cociente de riesgos (hazard ratio - HR) e intervalos del 95% de confianza (IC95%). Entre los 410.504 casos la letalidad global fue del 42,2%; el 51,4% en los más vulnerables. Por grupos de edad, se registra la presencia de una mayor letalidad a medida que empeora el estatus socioeconómico en todas las categorías; para 50-59 años es el doble. El modelo de Cox ajustado mostró un aumento del 32% en el riesgo de muerte (HR = 1,32; IC95%: 1,24-1,42). Además, los hombres de edad avanzada, de raza negra o indígena, con múltiples comorbilidades y sometidos a ventilación invasiva tienen un mayor riesgo de muerte tras la hospitalización. Es necesario que las medidas políticas intersectoriales se dirijan a mitigar los efectos de la pandemia de COVID-19 agravada por la vulnerabilidad social.

COVID-19 as the leading cause of hospital deaths in the Brazilian public health system in 2020.

OBJECTIVES: To describe the profile of hospital deaths in Brazil according to cause of admission during the pre-pandemic (2019) and pandemic periods (2020). METHODS: Descriptive study based on individual-level records of all hospital admissions with death outcomes reimbursed by the Brazilian National Health System in 2019 and 2020. RESULTS: The number of hospital deaths increased by 16.7% in 2020 compared with 2019 (522,686 vs 609,755). Coronavirus disease 2019 (COVID-19) was associated with 19.5% (118,879) of all hospital deaths in 2020, surpassing diseases of the circulatory system (15.4%, 93,735) and diseases of the respiratory system (14.9%, 91,035). CONCLUSIONS: COVID-19 was the main cause of death in public hospitals in Brazil in 2020.

Evaluation of the severe acute respiratory syndrome (SARS) surveillance system, with emphasis on influenza, Brazil, 2014-2016. / Avaliação do sistema de vigilância da síndrome respiratória aguda grave (SRAG) com ênfase em influenza, no Brasil, 2014 a 2016.

OBJECTIVE: to evaluate attributes of the severe acute respiratory syndrome (SARS) surveillance system in Brazil, 2014-2016. METHOD: this was an evaluation study conducted according to United States Centers for Disease Control and Prevention guidelines. Data from the Influenza Web information system notified for the period 2014-2016 were used. The simplicity, completeness, inconsistency, timeliness, acceptability, representativeness, positive predictive value (PPV) of the SARS case definition attributes and usefulness were evaluated. RESULTS: a simple structure was found with good completeness (100% for required variables; >95% for optional variables); low inconsistency (3.2%); lack of timeliness (68.2%); low acceptability (average of 70.4%); representative of the territory (capable of analyzing risk groups); high PPV (29.1%); useful (fulfils system objectives). CONCLUSION: the attributes evaluated indicate that the system is capable of providing complete, representative and useful information about influenza, adequate for guiding national health responses.

Trends in COVID-19 case-fatality rates in Brazilian public hospitals: A longitudinal cohort of 398,063 hospital admissions from 1st March to 3rd October 2020.

BACKGROUND: Almost 200,000 deaths from COVID-19 were reported in Brazil in 2020. The case fatality rate of a new infectious disease can vary by different risk factors and over time. We analysed the trends and associated factors of COVID-19 case fatality rates in Brazilian public hospital admissions during the first wave of the pandemic. METHODS: A retrospective cohort of all COVID-19-related admissions between epidemiological weeks 10-40 in the Brazilian Public Health System (SUS) was delimited from available reimbursement records. Smoothing time series and survival analyses were conducted to evaluate the trends of hospital case fatality rates (CFR) and the probability of death according to factors such as sex, age, ethnicity, comorbidities, length of stay and ICU use. RESULTS: With 398,063 admissions and 86,452 (21.7%) deaths, the overall age-standardized hospital CFR trend decreased throughout the period, varying from 31.8% (95%CI: 31.2 to 32.5%) in week 10 to 18.2% (95%CI: 17.6 to 18.8%) in week 40. This decreasing trend was observed in all sex, age, ethnic groups, length of stay and ICU admissions. Consistently, later admission (from July to September) was an independent protective factor. Patients 80+ year old had a hazard ratio of 8.18 (95% CI: 7.51 to 8.91). Ethnicity, comorbidities, and ICU need were also associated with the death risk. Although also decreasing, the CFR was always around 40-50% in people who needed an ICU admission. CONCLUSIONS: The overall hospital CFR of COVID-19 has decreased in Brazilian public hospitals during the first wave of the pandemic in 2020. Nevertheless, during the entire period, the CFR was still very high, suggesting the need for improving COVID-19 hospital care in Brazil.

Imputation method to reduce undetected severe acute respiratory infection cases during the coronavirus disease outbreak in Brazil

INTRODUCTION: The coronavirus disease (COVD-19) outbreak has overburdened the surveillance of severe acute respiratory infections (SARIs), including the laboratory network. This study was aimed at correcting the absence of laboratory results of reported SARI deaths. METHODS: The imputation method was applied for SARI deaths without laboratory information using clinico-epidemiological characteristics. RESULTS: Of 84,449 SARI deaths, 51% were confirmed with COVID-19 while 3% with other viral respiratory diseases. After the imputation method, 95% of deaths were reclassified as COVID-19 while 5% as other viral respiratory diseases. CONCLUSIONS: The imputation method was a useful and robust solution (sensitivity and positive predictive value of 98%) for missing values through clinical &epidemiological characteristics.

Imputation method to reduce undetected severe acute respiratory infection cases during the coronavirus disease outbreak in Brazil.

INTRODUCTION: The coronavirus disease (COVD-19) outbreak has overburdened the surveillance of severe acute respiratory infections (SARIs), including the laboratory network. This study was aimed at correcting the absence of laboratory results of reported SARI deaths. METHODS: The imputation method was applied for SARI deaths without laboratory information using clinico-epidemiological characteristics. RESULTS: Of 84,449 SARI deaths, 51% were confirmed with COVID-19 while 3% with other viral respiratory diseases. After the imputation method, 95% of deaths were reclassified as COVID-19 while 5% as other viral respiratory diseases. CONCLUSIONS: The imputation method was a useful and robust solution (sensitivity and positive predictive value of 98%) for missing values through clinical & epidemiological characteristics.

Covid-19: temporal evolution and immunization in the three epidemiological waves, Brazil, 2020-2022.

OBJECTIVE: Describe the temporal evolution of morbimortality due to Covid-19 and vaccination coverage during the health emergency in Brazil. METHODS: Number of cases and deaths due to Covid-19 were extracted from the public panel of the Brazilian Ministry of Health, according to epidemiological week (EW) and geographic region. Data on vaccines and variants were obtained, respectively, from the Information System of the National Immunization Program and the Genomic Surveillance System of SARS-CoV-2. RESULTS: Three peaks of deaths characterized the evolution of the Covid-19 pandemic: in EW 30 of 2020, in the EW 14 of 2021 and in the EW six of 2022; three case waves, starting in the North and Northeast regions, with higher rates in the third wave, mainly in the South region. Vaccination started in the epidemiological week three of 2021, rapidly reaching most of the population, particularly in the Southeast and South regions, coinciding with a reduction exclusively in the mortality rate in the third wave. Only from the beginning of the second wave, when Gama was the dominant variant, 146,718 genomes were sequenced. From the last EW of 2021, with vaccination coverage already approaching 70%, the Omicron variant caused an avalanche of cases, but with fewer deaths. CONCLUSIONS: We noticed the presence of three waves of Covid-19, as well as the effect of immunization on the reduction of mortality in the second and third waves, attributed to the Delta and Omicron variants, respectively. However, the reduction of morbidity, which peaked in the third wave during the domination of the Omicron variant, remained the same. The national and centralized command of the pandemic confrontation did not occur; thus, public administrators took the lead in their territories. The overwhelming effect of the pandemic could have been minimized, if there had been a coordinated participation of three spheres of the Brazilian Unified Health System administration, in the joint governance of the pandemic fight.