Vaccine Effectiveness against SARS-CoV-2 Variants in Adolescents from 15 to 90 Days after Second Dose: A Population-Based Test-Negative Case-Control Study.

OBJECTIVE: The objective of this study was to estimate the vaccine effectiveness (VE) against hospitalization and severe illness in adolescents due to infection with SARS-CoV-2 variants (gamma, delta, and omicron). STUDY DESIGN: A test-negative, case-control analysis was conducted in Brazil from July 2021 to March 2022. We enrolled 8458 eligible individuals (12-19 years of age) hospitalized with an acute respiratory syndrome, including 3075 cases with laboratory-proven COVID-19 and 4753 controls with negative tests for COVID-19. The primary exposure of interest was vaccination status. The primary outcome was SARS-CoV-2 infection during gamma/delta vs omicron-predominant periods. The aOR for the association of prior vaccination and outcomes was used to estimate VE. RESULTS: In the pre-omicron period, VE against COVID-19 hospitalization was 88% (95% CI, 83%-92%) and has dropped to 59% (95% CI, 49%-66%) during the omicron period. For hospitalized cases of COVID-19, considering the entire period of the analysis, 2-dose schedule was moderately effective against intensive care unit admission (46%, [95% CI, 27-60]), need of mechanical ventilation (49%, [95% CI, 32-70]), severe COVID-19 (42%, [95% CI, 17-60]), and death (46%, [95% CI, 8-67]). There was a substantial reduction of about 40% in the VE against all end points, except for death, during the omicron-predominant period. Among cases, 240 (6.6%) adolescents died; of fatal cases, 224 (93.3%) were not fully vaccinated. CONCLUSION: Among adolescents, the VE against all end points was substantially reduced during the omicron-predominant period. Our findings suggest that the 2-dose regimen may be insufficient for SARS-CoV-2 variants and support the need for updated vaccines to provide better protection against severe COVID-19.

Outcomes and risk factors for death among hospitalized children and adolescents with kidney diseases and COVID-19: an analysis of a nationwide database.

BACKGROUND: Patients with kidney diseases (KD) appear to be at particularly high risk for severe COVID-19. This study aimed to characterize the clinical outcomes and risk factors for COVID-19-related death in a large cohort of hospitalized pediatric patients with KD. METHODS: We performed an analysis of all pediatric patients with KD and COVID-19 registered in SIVEP-Gripe, a Brazilian nationwide surveillance database, between February 16, 2020, and May 29, 2021. The primary outcome was time to death, which was evaluated considering discharge as a competitive risk by using cumulative incidence function. RESULTS: Among 21,591 hospitalized patients with COVID-19, 290 cases (1.3%) had KD. Of these, 59 (20.8%) had a fatal outcome compared with 7.5% of the non-KD cohort (P < 0.001). Pediatric patients with KD had an increased hazard of death compared with the non-KD cohort (Hazard ratio [HR] = 2.85, 95% CI 2.21-3.68, P < 0.0001). After adjustment, the factors associated with the death among KD patients were living in Northeast (HR 2.16, 95% CI 1.13-4.31) or North regions (HR 3.50, 95% CI 1.57-7.80), oxygen saturation < 95% at presentation (HR 2.31, 95% CI 1.30-4.10), and presence of two or more associated comorbidities (HR 2.10, 95% CI 1.08-4.04). CONCLUSIONS: Children and adolescents with KD had a higher risk of death compared with the non-KD cohort. The higher risk was associated with low oxygen saturation at admission, living in socioeconomically disadvantaged regions, and presence of other pre-existing comorbidities. A higher resolution version of the Graphical abstract is available as Supplementary information.

Clinical Impact and Risk Factors of Mortality in Hospitalized Children and Adolescents With Hematologic Diseases and COVID-19: An Observational Retrospective Cohort Study.

This study aimed to evaluate the risk factors for COVID-19-related death in a large cohort of hospitalized children with hematological disorders. We performed an analysis of all pediatric patients with COVID-19 registered in a Brazilian nationwide surveillance database between February 2020 and May 2021. The primary outcome was time to death, which was evaluated considering discharge as a competitive risk by using the cumulative incidence function. Among 21,591 hospitalized pediatric patients with COVID-19, 596 cases (2.8%) had hematological diseases. Sixty-one children (27.4%) with malignant hematological diseases had a fatal outcome as compared with 4.2% and 7.4% of nonmalignant hematological and nonhematological cohorts, respectively ( P <0.0001). Children with hematological diseases had a significant increased hazard of death compared with those without these conditions (hazard ratio [HR],=2.40, 95% confidence interval, 1.98 - 2.91). In multivariable analysis, the factors associated with death were the presence of malignant hematological disease (HR, 2.22, 95% CI 1.47 - 3.36), age >10 years (HR 2.19, 95% CI 1.46 - 3.19), male (HR 1.52, 95% CI 1.02 - 2.27), oxygen saturation <95% (HR 2.02, 95% CI 1.38 - 2.96), and abdominal pain at admission (HR 2.75, 95% CI 1.76 - 4.27). Children with malignant hematological diseases had a higher risk of death compared with those without these disorders.

Comparison of the First and Second Waves of the Coronavirus Disease 2019 Pandemic in Children and Adolescents in a Middle-Income Country: Clinical Impact Associated with Severe Acute Respiratory Syndrome Coronavirus 2 Gamma Lineage.

OBJECTIVE: To evaluate the severity and clinical outcomes of the SARS-CoV-2 gamma variant in children and adolescents hospitalized with COVID-19 in Brazil. STUDY DESIGN: In this observational retrospective cohort study, we performed an analysis of all 21 591 hospitalized patients aged <20 years with confirmed SARS-CoV-2 infection registered in a national database in Brazil. The cohort was divided into 2 groups according to the predominance of SARS-CoV-2 lineages (WAVE1, n = 11 574; WAVE2, n = 10 017). The characteristics of interest were age, sex, geographic region, ethnicity, clinical presentation, and comorbidities. The primary outcome was time to death, which was evaluated by competing-risks analysis, using cumulative incidence functions. A predictive Fine and Gray competing-risks model was developed based on the WAVE1 cohort with temporal validation in the WAVE2 cohort. RESULTS: Compared with children and adolescents admitted during the first wave, those admitted during the second wave had significantly more hypoxemia (52.5% vs 41.1%; P < .0001) and intensive care unit admissions (28.3% vs 24.9%; P < .0001) and needed more noninvasive ventilatory support (37.3% vs 31.6%; P < .0001). In-hospital deaths and death rates were 896 (7.7%) in the first wave and 765 (7.6%) in the second wave (P = .07). The prediction model of death included age, ethnicity, region, respiratory symptoms, and comorbidities. In the validation set (WAVE2), the C statistic was 0.750 (95% CI, 0.741-0.758; P < .0001). CONCLUSIONS: This large national study found a more severe spectrum of risk for pediatric patients with COVID-19 caused by the gamma variant. However, there was no difference regarding the probability of death between the waves.

Risk factors for COVID-19-related mortality in hospitalized children and adolescents with diabetes mellitus: An observational retrospective cohort study.

BACKGROUND: Diabetes has been recognized as a major comorbidity for COVID-19 severity in adults. This study aimed to characterize the clinical outcomes and risk factors for COVID-19-related death in a large cohort of hospitalized pediatric patients with diabetes. METHODS: We performed an analysis of all pediatric patients with diabetes and COVID-19 registered in SIVEP-Gripe, a Brazilian nationwide surveillance database, between February 2020 and May 2021. The primary outcome was time to death, which was evaluated considering discharge as a competitive risk by using cumulative incidence function. RESULTS: Among 21,591 hospitalized pediatric patients with COVID-19, 379 (1.8%) had diabetes. Overall, children and adolescents with diabetes had a higher prevalence of ICU admission (46.6% vs. 26%), invasive ventilation (16.9% vs. 10.3%), and death (15% vs. 7.6%) (all P < 0.0001). Children with diabetes had twice the hazard of death compared with pediatric patients without diabetes (Hazard ratio [HR] = 2.0, 95% CI, 1.58-2.66). Among children with diabetes, four covariates were independently associated with the primary outcome, living in the poorest regions of the country (Northeast, HR, 2.17, 95% CI 1.18-4.01, and North, (HR 4.0, 95% CI 1.79-8.94), oxygen saturation < 95% at admission (HR 2.97, 95% CI 1.64-5.36), presence of kidney disorders (HR 3.39, 95% CI 1.42-8.09), and presence of obesity (HR 3.77, 95% CI 1.83-7.76). CONCLUSION: Children and adolescents with diabetes had a higher risk of death compared with patients without diabetes. The higher risk of death was associated with clinical and socioeconomic factors.

Postnatal urinary tract dilatation classification: improvement of the accuracy in predicting kidney injury.

BACKGROUND: The grading of urinary tract dilatation (UTD) on postnatal sonography is a fundamental step to establish rational management for infants with antenatal hydronephrosis (ANH). The aim of this study was to compare the prediction accuracy of UTD grading systems for relevant clinical outcomes. In addition, we propose a refinement of the UTD classification by adding quantitative measurements and evaluate its impact on accuracy. METHODS: Between 1989 and 2019, 447 infants diagnosed with isolated AHN were prospectively followed. The events of interest were surgical interventions and kidney injury. Comparison of performance of the grading systems and the impact on the accuracy of a modified UTD classification (including the size of the kidney parenchyma) was assessed by the area under the receiver-operating characteristic curve (AUC). RESULTS: Of 447 infants, 131 (29%) underwent surgical intervention and 26 (5.8%) had developed kidney injury. The median follow-up time was 9 years (IQ range, 7-12 years). The performance for detecting the need for surgical intervention was excellent for all grading systems (AUC > 0.90). However, for predicting kidney injury, the modified UTD classification exhibited significant improvement in accuracy (AUC = 0.913, 95%CI, 0.883-0.937) as compared with UTD classification (AUC = 0.887, 95%CI, 0.854-0.915) (P = 0.027). CONCLUSIONS: Our study confirms that the hydronephrosis grading systems provide excellent accuracy in discriminating patients who need surgical intervention among infants with AHN. Our findings suggest that the inclusion of kidney parenchymal thickness to UTD classification might increase the accuracy for predicting infants who may develop kidney injury. A higher resolution version of the Graphical abstract is available as Supplementary information.

Global scientific production in the pre-Covid-19 Era: An analysis of 53 countries for 22 years.

Based on an extensive analysis of public databases, we provide an overview of the global scientific output and describe the dynamics of the profound changes in the scientific enterprise during the last decades. The analysis included the scientific production of 53 countries over the 1996-2018 period. During this period, the production of articles per year has tripled. There was a strong correlation between the growth of the global gross domestic product and the increase in the number of articles (R2 = 0.973, P<0.001). Six countries showed a robust increment of their scientific production and are currently among the top 20 in the ranking of world scientific production (China, India, South Korea, Brazil, Turkey, and Iran). The mean annual growth rate was about 12.7% for these six countries. The share of the global scientific production of these countries increased from 7% in 1996 to 27.8% in 2018. Conversely, the participation of the 10 most traditional countries has dropped from 73% to 45% during the same period. In conclusion, we believe that our findings may contribute to further studies aiming to evaluate the impact and changes of the scientific endeavor over the next years in light of the forthcoming new world framework.

COVID-19 pandemic and the answer of science: a year in review.

The world is looking forward to a prompt response by the scientific community in order to overcome the first pandemic of the 21st century. This study aimed to provide an overview of scientific output on COVID-19 during its first year. We assembled information regarding 60,830 articles related to COVID-19 indexed in the WoS database from January 24 to December 13, 2020. Only 4 countries accounted for about 60% of the articles (USA, China, Italy, and England) and 12 countries accounted for about 95% of the world scientific output on COVID-19 (USA, China, Italy, England, India, Canada, Germany, Spain, Australia, Brazil, Iran, and Turkey). 25 research centers around the world contributed with more than 500 papers on COVID-19. Papers were scattered throughout 6,133 journals, with 12 journals with > 250 articles. 20 articles (0.03%) have already received more than the 1,000 citations. The response of the scientific endeavor to this acute global public health emergency has been fast and robust. The overview provided by the analysis of the scientific response to the pandemic may contribute to further studies aiming to evaluate the impact and changes in the scientific endeavor for the next years in light of the forthcoming new world framework.

The association between pre-existing asthma and reduced risk of death among children and adolescents hospitalized with COVID-19 in Brazil.

OBJECTIVE: There have been conflicting reports on the relationship between asthma and COVID-19 severity. This study aimed to compare the risk of death among children with asthma and healthy peers hospitalized due to COVID-19. METHODS: We carried out an analysis of all pediatric patients 2-19 years of age with asthma and COVID-19 registered in Influenza Epidemiological Surveillance Information System-Gripe, a Brazilian nationwide surveillance database, between February 2020 and March 2022. The primary outcome was time to death, which was evaluated considering discharge as a competitive risk using the cumulative incidence function. RESULTS: Among 30,405 hospitalized children with COVID-19, 21,340 (70.2%) had no comorbidities, 6444 (21.2%) had comorbidities other than asthma, 2165 (7.1%) had asthma, and 465 (1.5%) had asthma with other comorbidities. The estimated probability of a fatal outcome for each group was 4.1%, 14.9%, 2.1%, and 10.7%, respectively. After adjustment, children with asthma had a 60% reduction in the hazard of death than healthy peers (hazard ratio [HR] = 0.39, 95% confidence interval [CI], 0.29-0.53, p < 0.0001). Among children with asthma and no other comorbidities, two covariates were independently associated with in-hospital mortality, age ≥12 years, HR = 4.0, 95% CI, 2.5-6.4), and low oxygen saturation at admission (HR = 2.3, 95% CI, 1.4-3.2). CONCLUSION: Children with asthma and no comorbidities had a lower risk of death compared with healthy peers after controlling for clinical and demographic confounding factors.

Effectiveness of BNT162b2 and CoronaVac vaccines against omicron in children aged 5 to 11 years.

BACKGROUND: This study aimed to estimate vaccine effectiveness (VE) against omicron variant infection and severe corona virus disease 2019 (COVID-19) in children aged 5-11 years hospitalized with acute respiratory syndrome. METHODS: A test-negative, case-control analysis was conducted from February 2022 to June 2022. We enrolled 6950 eligible children, including 1102 cases and 5848 controls. VE was calculated after immunization with one and two doses of BNT162b2 or CoronaVac. The outcomes were hospitalization with acute respiratory symptoms and detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and severe COVID-19. The adjusted odds ratio for the association of prior vaccination and outcomes was used to estimate VE. RESULTS: For fully vaccinated children, the overall estimated VE against hospitalization with SARS-CoV-2 infection was 42% [95% confidence interval (CI) 26 to 54]. VE peaked at 29-42 days (67%, 95% CI 40% to 82%) and then declined to 19% (95% CI, - 20% to 45%) at 57-120 days after the second dose. The BNT162b2 vaccine had a similar VE against hospitalization with SARS-CoV-2 infection (45%, 95% CI, 20 to 61) compared to the CoronaVac vaccine (40%, 95% CI, 17% to 56%). Among cases, 56 (5%) children died; 53 (94.6%) were not fully vaccinated. For cases, the two-dose schedule effectiveness against ICU admission, need for invasive ventilation, severe illness, and death were 10% (95% CI, - 54%-45%), 22% (95% CI - 70%-68%), 12% (95% CI, - 62%-52%), and 16% (95% CI, - 77%-75%), respectively. CONCLUSIONS: For hospitalized children aged 5-11 years during the omicron-predominant period in Brazil, two doses of both vaccines had moderate effectiveness against hospitalization with acute respiratory symptoms and SARS-CoV-2 infection and offered limited protection against endpoints of COVID-19 severity.

Outcomes and risk factors of death among hospitalized children and adolescents with obesity and COVID-19 in Brazil: An analysis of a nationwide database.

BACKGROUND: Obesity is a well-recognized risk factor for critical illness and death among adult patients with SARS-CoV-2 infection. OBJECTIVE: This study aimed to characterize the clinical outcomes and risk factors of death related to obesity in a cohort of hospitalized paediatric patients with COVID-19. METHODS: We performed an analysis of all paediatric patients with obesity and COVID-19 registered in SIVEP-Gripe, a Brazilian nationwide surveillance database, between February 2020 and May 2021. The primary outcome was time to death, which was evaluated by using cumulative incidence function. RESULTS: Among 21 591 hospitalized paediatric patients with COVID-19, 477 cases (2.2%) had obesity. Of them, 71 (14.9%) had a fatal outcome as compared with 7.5% for patients without obesity (hazard ratio [HR] = 2.0, 95% confidence interval [CI] 1.59-2.53, p < 0.001). After adjustment, the factors associated with death among patients with obesity were female gender (HR = 2.8, 95% CI 1.70-4.61), oxygen saturation < 95% (HR = 2.58, 95% CI 1.38-4.79), presence of one (HR = 1.91, 95% CI 1.11-3.26), and two or more comorbidities (HR = 4.0, 95% CI 2.21-7.56). CONCLUSIONS: Children and adolescents with obesity had higher risk of death compared with those without obesity. The higher risk of death was associated with female gender, low oxygen saturation at admission, and presence of other comorbidities.

Clinical characteristics and risk factors for death among hospitalised children and adolescents with COVID-19 in Brazil: an analysis of a nationwide database.

BACKGROUND: COVID-19 is usually less severe and has lower case fatality in children than in adults. We aimed to characterise the clinical features of children and adolescents hospitalised with laboratory-confirmed SARS-CoV-2 infection and to evaluate the risk factors for COVID-19-related death in this population. METHODS: We did an analysis of all patients younger than 20 years who had quantitative RT-PCR-confirmed COVID-19 and were registered in the Influenza Epidemiological Surveillance Information System (SIVEP-Gripe, a nationwide surveillance database of patients admitted to hospital with severe acute respiratory disease in Brazil), between Feb 16, 2020, and Jan 9, 2021. The primary outcome was time to recovery (discharge) or in-hospital death, evaluated by competing risks analysis using the cumulative incidence function. FINDINGS: Of the 82 055 patients younger than 20 years reported to SIVEP-Gripe during the study period, 11 613 (14·2%) had available data showing laboratory-confirmed SARS-CoV-2 infection and were included in the sample. Among these patients, 886 (7·6%) died in hospital (at a median 6 days [IQR 3-15] after hospital admission), 10 041 (86·5%) patients were discharged from the hospital, 369 (3·2%) were in hospital at the time of analysis, and 317 (2·7%) were missing information on outcome. The estimated probability of death was 4·8% during the first 10 days after hospital admission, 6·7% during the first 20 days, and 8·1% at the end of follow-up. Probability of discharge was 54·1% during the first 10 days, 78·4% during the first 20 days, and 92·0% at the end of follow-up. Our competing risks multivariate survival analysis showed that risk of death was increased in infants younger than 2 years (hazard ratio 2·36 [95% CI 1·94-2·88]) or adolescents aged 12-19 years (2·23 [1·84-2·71]) relative to children aged 2-11 years; those of Indigenous ethnicity (3·36 [2·15-5·24]) relative to those of White ethnicity; those living in the Northeast region (2·06 [1·68-2·52]) or North region (1·55 [1·22-1·98]) relative to those in the Southeast region; and those with one (2·96 [2·52-3·47]), two (4·96 [3·80-6·48]), or three or more (7·28 [4·56-11·6]) pre-existing medical conditions relative to those with none. INTERPRETATION: Death from COVID-19 was associated with age, Indigenous ethnicity, poor geopolitical region, and pre-existing medical conditions. Disparities in health care, poverty, and comorbidities can contribute to magnifying the burden of COVID-19 in more vulnerable and socioeconomically disadvantaged children and adolescents in Brazil. FUNDING: National Council for Scientific and Technological Development, Research Support Foundation of Minas Gerais.