ABSTRACT
Compared to previous variants, the SARS-CoV-2 B.1.1.529 (Omicron) variant has relatively high infection rates, including among children. Even though severe COVID-19 in children is rare, this group is susceptible to the multisystem inflammatory syndrome in Children (MIS-C), long-COVID and downstream effects of COVID-19, including social isolation and education disruption. There is evidence that vaccination with an mRNA vaccine offers protection against infection and severe forms of COVID-19 for children. However, data on the effectiveness of inactivated virus vaccine, the most used platform worldwide, is scarce during the Omicron period. In Brazil, children between 6 to 11 years are eligible to receive the CoronaVac vaccine. Using a national linked database from January 21, 2022, up to April 19, 2022, during the Omicron dominant period in Brazil, we conducted a test-negative design with 194,258 tests to assess CoronaVac effectiveness against infection and severe (hospitalisation or death) outcomes among children aged 6 to 11 years. The estimated VE for symptomatic infection was 35.0% (95% CI 27.7–41.5) at 0–13 days and 41.5% (95% CI: 34.4–47.7) at ≥ 14 days post-second dose. For severe outcomes (hospitalisation or death) VE was 69.2% (95% CI: 11.7–93.6) at 0–13 days and 63.5% (95% CI: 5.8–90.0). Two doses of CoronaVac in children during the Omicron period showed low levels of protection against symptomatic infection, and modest levels against severe illness.
Subject(s)
COVID-19ABSTRACT
Background: Socio-economic factors have been consistently associated with suicide, and economic recessions are linked to rising suicide rates. This study investigates the effect of the world`s largest conditional cash transfer (CCT) programme on suicide rates in a cohort of half the Brazilian population. Methods: We used data from the 100 Million Brazilian Cohort, covering a 12-year period (2004 to 2015). It comprises socio-economic and demographic information on 114,008,317 individuals, linked to the “Bolsa Família” programme (BFP) payroll database, and nationwide death registration data. We fitted Poisson models to estimate the incidence rate ratios for suicide, associated with exposure to the BFP and Propensity Score (PS) to group BFP beneficiaries and non-beneficiaries. We estimated the PS through multiple logistic regression using baseline socio-demographic and economic characteristics and year of registration, and ran Kernel matching analysis and several sensitivity tests. Results: In the main analysis, 33,281 suicide cases occurred among the 69,707,312 individuals followed for 305,229,883 person-years at risk. Suicide rates among beneficiaries and non-beneficiaries were 5.5 (95%CI=5.44, 5.61) and 11.1 (95%CI=10.41, 11.81) in the matched cohort and 5.4 (95%CI=5.32, 5.47) and 10.7 (95%CI=10.51, 10.87) per 100,000 individuals, in the original cohorts. BFP beneficiaries had a 61% lower suicide rate than non-beneficiaries (IRR=0.39, 95%CI=0.37,0.41) in the main analysis and similar results in all sensitivity analyses. This effect was higher among women (IRR=0.35, 95%IC=0.31,0.39), and younger individuals (IRR=0.40, 95%IC=0.37,0.44). Interpretation: CCT programs play an important role in poverty reduction and well-being improvement for beneficiaries. We have also demonstrated that it contributes towards reduced suicide rates. Targeting social determinants, using cash transfer programmes, could be important tools to limit suicide, predicted to rise in the aftermath of the economic recession, consequent to the Covid-19 pandemic.Funding Statement: The authors received no direct financial support for this article. During the study DBM held a research associate scholarship from Wellcome Trust (202912/Z/16/Z) and CIDACS has received support from the Department of Science and Technology, from the Brazilian Ministry of Health; National Research Council (CNPq), Brazil; Bill and Melinda Gates Foundation (CHAMADA MCTI/CNPq/MS/SCTIE/Decit/Fundação Bill e Melinda Gates N o 47/2014); Health Surveillance Secretariat, Ministry of Health, Brazil; Fundação de Apoio a Pesquisa do Estado da Bahia (FAPESB); Financiadora de Estudos e Projetos (FINEP); Secretaria de Ciência e Tecnologia do Estado da Bahia (SECTI), and Wellcome Trust.Declaration of Interests: All authors have no competing interests.Ethics Approval Statement: This study was approved by the two research ethics committees of the: (i) Federal University of Bahia (application number: 1023107) and (ii) London School of Hygiene & Tropical Medicine (application number: 11581).
Subject(s)
Multiple Sclerosis , COVID-19ABSTRACT
Social isolation has affected a large number of people and may lead to impairment of physical and mental health. Although stress resulting from social isolation may increase cancer progression, its interference on tumorigenesis is poorly known. In this study, we used a preclinical model to evaluate the effects of social isolation stress on chemically induced oral carcinogenesis. Sixty-two 21-day-old male Wistar rats were divided into isolated and grouped groups. After 90 days of age, the rats from both groups underwent oral carcinogenesis with 4-nitroquinoline 1-oxide (4NQO) for 20 weeks. All rats were assessed for depressive-like behavior and euthanized for oral squamous cell carcinoma (OSCC) diagnosis and measurement of inflammatory mediators in the tumor microenvironment. Social isolation stress increased the OSCC occurrence by 20.4% when compared to control. Isolated rats also showed higher tumor volume and cachexia than the grouped rats. Social isolation did not induce changes in the depressive-like behavior after carcinogenic induction. Tumors from stressed rats had increased levels of the inflammatory mediators, TNF-alpha, IL1-beta and MCP-1. The concentrations of TNF-alpha and MCP-1 were significantly increased in the large tumors from isolated animals. Higher tumor levels of TNF-alpha, IL-6, IL1-beta and MCP-1 were positively correlated with OSCC growth. This study provides the first evidence that social isolation stress may facilitate OSCC occurrence and tumor progression, an event accompanied by increased local levels of inflammatory mediators.