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1.
Prev Sci ; 25(5): 834-848, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38954125

RESUMO

Violence is a major public health problem globally, with the highest rates in low- and middle-income countries (LMICs) in the Americas and southern Africa. Parenting programmes in high-income countries can diminish risk for violence, by reducing risk factors such as child aggression and harsh parenting, and increasing protective factors such as child cognitive development and school readiness. However, there is critical need to identify low-cost programmes with replicable benefits that work in real-world LMICs contexts. A three-arm, randomised, single-blind trial evaluated effects of two low-cost, group-based parenting programmes recommended for LMICs (ACT: Raising Safe Kids; DBS: dialogic book-sharing) on child aggression (primary outcome), child development, parenting, maltreatment, and stress. Participants were 369 children with medium-high levels of aggression (mean age 3.1 years at baseline) in poor households. Interventions were implemented in city health and education services in southern Brazil. Maternal reports, filmed observations, child tasks, and hair cortisol were assessed at baseline, 1-month post-intervention, and 8-month follow-up. Intention-to-treat analyses compared each of ACT and DBS with a control group. Three hundred sixty-eight (99.7%) participants completed follow-up assessments 8 months after the interventions. There was no effect of ACT (standardised mean difference, SMD 0.11, 95% CI - 0.05, 0.27) or DBS (SMD 0.05, 95% CI - 0.11, 0.21) on the primary outcome of child aggression. ACT reduced harsh parenting behaviour post-intervention (SMD - 0.23; 95% CI - 0.46, - 0.01), but not at follow-up. DBS improved book-sharing practices at both time points (e.g., maternal sensitivity at follow-up SMD 0.33; 95% CI 0.08, 0.57). There were no benefits of either programme for other parenting, child development, or stress outcomes. Two parenting programmes in Brazil had small effects on parenting practices but did not reduce child aggression or several other important risk/protective factors for violence. Effective early interventions that reduce violence in real-world LMIC settings are highly desirable but may be challenging to achieve.


Assuntos
Agressão , Poder Familiar , Violência , Humanos , Brasil , Pré-Escolar , Feminino , Masculino , Violência/prevenção & controle , Método Simples-Cego , Criança , Fatores de Risco
2.
Health Technol Assess ; 28(34): 1-109, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39046101

RESUMO

Background: Vaccination of infants with pneumococcal conjugate vaccines is recommended by the World Health Organization. Evidence is mixed regarding the differences in immunogenicity and efficacy of the different pneumococcal vaccines. Objectives: The primary objective was to compare the immunogenicity of pneumococcal conjugate vaccine-10 versus pneumococcal conjugate vaccine-13. The main secondary objective was to compare the seroefficacy of pneumococcal conjugate vaccine-10 versus pneumococcal conjugate vaccine-13. Methods: We searched the Cochrane Library, EMBASE, Global Health, MEDLINE, ClinicalTrials.gov and trialsearch.who.int up to July 2022. Studies were eligible if they directly compared either pneumococcal conjugate vaccine-7, pneumococcal conjugate vaccine-10 or pneumococcal conjugate vaccine-13 in randomised trials of children under 2 years of age, and provided immunogenicity data for at least one time point. Individual participant data were requested and aggregate data used otherwise. Outcomes included the geometric mean ratio of serotype-specific immunoglobulin G and the relative risk of seroinfection. Seroinfection was defined for each individual as a rise in antibody between the post-primary vaccination series time point and the booster dose, evidence of presumed subclinical infection. Each trial was analysed to obtain the log of the ratio of geometric means and its standard error. The relative risk of seroinfection ('seroefficacy') was estimated by comparing the proportion of participants with seroinfection between vaccine groups. The log-geometric mean ratios, log-relative risks and their standard errors constituted the input data for evidence synthesis. For serotypes contained in all three vaccines, evidence could be synthesised using a network meta-analysis. For other serotypes, meta-analysis was used. Results from seroefficacy analyses were incorporated into a mathematical model of pneumococcal transmission dynamics to compare the differential impact of pneumococcal conjugate vaccine-10 and pneumococcal conjugate vaccine-13 introduction on invasive pneumococcal disease cases. The model estimated the impact of vaccine introduction over a 25-year time period and an economic evaluation was conducted. Results: In total, 47 studies were eligible from 38 countries. Twenty-eight and 12 studies with data available were included in immunogenicity and seroefficacy analyses, respectively. Geometric mean ratios comparing pneumococcal conjugate vaccine-13 versus pneumococcal conjugate vaccine-10 favoured pneumococcal conjugate vaccine-13 for serotypes 4, 9V and 23F at 1 month after primary vaccination series, with 1.14- to 1.54-fold significantly higher immunoglobulin G responses with pneumococcal conjugate vaccine-13. Risk of seroinfection prior to the time of booster dose was lower for pneumococcal conjugate vaccine-13 for serotype 4, 6B, 9V, 18C and 23F than for pneumococcal conjugate vaccine-10. Significant heterogeneity and inconsistency were present for most serotypes and for both outcomes. Twofold higher antibody after primary vaccination was associated with a 54% decrease in risk of seroinfection (relative risk 0.46, 95% confidence interval 0.23 to 0.96). In modelled scenarios, pneumococcal conjugate vaccine-13 or pneumococcal conjugate vaccine-10 introduction in 2006 resulted in a reduction in cases that was less rapid for pneumococcal conjugate vaccine-10 than for pneumococcal conjugate vaccine-13. The pneumococcal conjugate vaccine-13 programme was predicted to avoid an additional 2808 (95% confidence interval 2690 to 2925) cases of invasive pneumococcal disease compared with pneumococcal conjugate vaccine-10 introduction between 2006 and 2030. Limitations: Analyses used data from infant vaccine studies with blood samples taken prior to a booster dose. The impact of extrapolating pre-booster efficacy to post-booster time points is unknown. Network meta-analysis models contained significant heterogeneity which may lead to bias. Conclusions: Serotype-specific differences were found in immunogenicity and seroefficacy between pneumococcal conjugate vaccine-13 and pneumococcal conjugate vaccine-10. Higher antibody response after vaccination was associated with a lower risk of subsequent infection. These methods can be used to compare the pneumococcal conjugate vaccines and optimise vaccination strategies. For future work, seroefficacy estimates can be determined for other pneumococcal vaccines, which could contribute to licensing or policy decisions for new pneumococcal vaccines. Study registration: This study is registered as PROSPERO CRD42019124580. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 17/148/03) and is published in full in Health Technology Assessment; Vol. 28, No. 34. See the NIHR Funding and Awards website for further award information.


Pneumococcal disease is a serious illness caused by a bacterial infection that can result in death. Children in the United Kingdom receive a vaccine to prevent this disease that protects against 13 different types of pneumococcal diseases. It is very effective, but other vaccines are also available, such as one that contains 10 types of pneumococcal diseases. Vaccines in the United Kingdom are bought by the government and the choice of which vaccine to provide is based on the cost of the vaccine as well as the benefits to our health. However, there is very little information comparing different vaccines and it is often assumed they are the same. We did a large analysis combining all studies of the two main licensed pneumococcal vaccines to determine which vaccine provides better protection against infection and how this affects costs. We used information from studies published in medical journals, and also data from studies done by the companies that own the vaccines. Our results showed that pneumococcal conjugate vaccine-13 vaccine provided better protection than pneumococcal conjugate vaccine-10 for 5 of the 10 serotypes that are contained in both vaccines. When we used these results to model what might have happened had either of these vaccines been introduced into the United Kingdom vaccination programme in 2006, we found that both vaccines caused a rapid decrease in the amount of disease, but that the decrease in disease was faster with pneumococcal conjugate vaccine-13 than pneumococcal conjugate vaccine-10. This resulted in 2808 cases of diseases prevented over a 25-year time frame with pneumococcal conjugate vaccine-13 compared with pneumococcal conjugate vaccine-10. Our methods can be used to compare other vaccines and we recommend this type of study be done in future when making decisions on vaccine product choice.


Assuntos
Metanálise em Rede , Infecções Pneumocócicas , Vacinas Pneumocócicas , Vacinas Conjugadas , Humanos , Vacinas Pneumocócicas/imunologia , Vacinas Pneumocócicas/administração & dosagem , Vacinas Conjugadas/imunologia , Infecções Pneumocócicas/prevenção & controle , Infecções Pneumocócicas/imunologia , Lactente , Streptococcus pneumoniae/imunologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Imunogenicidade da Vacina
3.
Vaccine ; : 126167, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060202

RESUMO

BACKGROUND: For pathogens which cause infections that present asymptomatically, evaluating vaccine efficacy (VE) against asymptomatic infection is important for understanding a vaccine's potential epidemiological impact. Regular testing for subclinical infections is a potentially valuable strategy but its success hinges on participant adherence and minimising false positives. This paper describes the implementation and adherence to weekly testing in a COVID-19 vaccine trial. METHODS: COV002 was a phase 2/3 trial assessing the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2. Asymptomatic infections were detected using weekly self-administered swabs for RT-PCR testing. We analysed adherence using mixed-effects regression models and estimated the probability of true and false positive asymptomatic infections using estimates of adherence and testing characteristics. FINDINGS: 356,551 tests were self-administered by 10,811 participants during the 13-month follow-up. Median adherence was 75.0% (IQR 42·6-90·9), which translated to a 74·5% (IQR 50·9-78·8) probability of detecting a positive asymptomatic infection during the swabbing period, and between 21 and 96 false positives during VE evaluation. The odds of returning a swab declined by 8% per week and further after testing positive and unblinding. Adherence was higher in older age groups, females and non-healthcare workers. INTERPRETATION: The COV002 trial demonstrated the feasibility of running a long-term regular asymptomatic testing strategy. This information could be valuable for designing future phase III vaccine trials in which infection is an outcome. FUNDING: UK Research and Innovation, National Institutes for Health Research (NIHR), Coalition for Epidemic Preparedness Innovations, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, AstraZeneca.

4.
BMJ Open ; 14(6): e077271, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38885988

RESUMO

INTRODUCTION: In 2020, the UK government established a large-scale testing programme to rapidly identify individuals in England who were infected with SARS-CoV-2 and had COVID-19. This comprised part of the UK government's COVID-19 response strategy, to protect those at risk of severe COVID-19 disease and death and to reduce the burden on the health system. To assess the success of this approach, the UK Health Security Agency (UKHSA) commissioned an independent evaluation of the activities delivered by the National Health System testing programme in England. The primary purpose of this evaluation will be to capture key learnings from the roll-out of testing to different target populations via various testing services between October 2020 and March 2022 and to use these insights to formulate recommendations for future pandemic preparedness strategy. In this protocol, we detail the rationale, approach and study design. METHODS AND ANALYSIS: The proposed study involves a stepwise mixed-methods approach, aligned with established methods for the evaluation of complex interventions in health, to retrospectively assess the combined impact of key asymptomatic and symptomatic testing services nationally. The research team will first develop a theory of change, formulated in collaboration with testing service stakeholders, to understand the causal pathways and intended and unintended outcomes of each testing service and explore contextual impacts on each testing service's intended outcomes. Insights gained will help identify indicators to evaluate how the combined aims of the testing programme were achieved, using a mixed-methods approach. ETHICS AND DISSEMINATION: The study protocol was granted ethics approval by the UKHSA Research Ethics and Governance Group (reference NR0347). All relevant ethics guidelines will be followed throughout. Findings arising from this evaluation will be used to inform lessons learnt and recommendations for UKHSA on appropriate pandemic preparedness testing programme designs; findings will also be disseminated in peer-reviewed journals, a publicly available report to be published online and at academic conferences. The final report of findings from the evaluation will be used as part of a portfolio of evidence produced for the independent COVID-19 government inquiry in the UK. TRANSPARENCY DECLARATION: The lead author (the manuscript's guarantor) affirms that the manuscript is an honest, accurate and transparent account of the study being reported; no important aspects of the study have been omitted, and any discrepancies from the study as planned have been explained.


Assuntos
Teste para COVID-19 , COVID-19 , Pandemias , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/diagnóstico , Inglaterra/epidemiologia , Teste para COVID-19/métodos , Projetos de Pesquisa , Estudos Retrospectivos
5.
Pediatr Infect Dis J ; 43(2): e67-e70, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38758207

RESUMO

We evaluated whether the quantification of IgG to pneumococcal capsular polysaccharides is an accurate diagnostic test for pneumococcal infection in children with pneumonia in Nepal. Children with pneumococcal pneumonia did not have higher convalescent, or higher fold change, IgG to pneumococcal polysaccharides than children with other causes of pneumonia. Caution is needed in interpreting antibody responses in pneumococcal infections.


Assuntos
Anticorpos Antibacterianos , Infecções Comunitárias Adquiridas , Imunoglobulina G , Pneumonia Pneumocócica , Polissacarídeos Bacterianos , Streptococcus pneumoniae , Humanos , Anticorpos Antibacterianos/sangue , Pré-Escolar , Polissacarídeos Bacterianos/imunologia , Imunoglobulina G/sangue , Lactente , Streptococcus pneumoniae/imunologia , Pneumonia Pneumocócica/diagnóstico , Pneumonia Pneumocócica/imunologia , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/imunologia , Masculino , Feminino , Criança , Nepal , Cápsulas Bacterianas/imunologia
6.
Vaccine ; 42(13): 3230-3238, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38627147

RESUMO

INTRODUCTION: Capsular polysaccharide (CPS) serotype-specific Immunoglobulin G (IgG) in cord blood has been proposed as a correlate of protection against invasive Group B Streptococcus (iGBS) disease. Although protective levels are required in infants throughout the window of vulnerability up to 3 months of age, little is known regarding the kinetics of GBS-specific IgG over this period. METHODS: We enrolled 33 healthy infants born to mothers colonized with GBS. We collected cord blood and infant blood samples either at one (21-35 days), two (49-63 days), or three months of age (77-91 days). We measured GBS serotype-specific CPS IgG concentrations and calculated the decay rate using a mixed-effects model. We further explored whether the antibody kinetics were affected by common maternal and infant factors and estimated the correlation between IgG concentration at birth and one, two, and three months of age. RESULTS: The half-life estimate of IgG concentration for homologous and non-homologous GBS serotypes in paired samples with detectable IgG levels at both time points was 27.4 (95 % CI: 23.5-32.9) days. The decay rate did not vary by maternal age (p = 0.7), ethnicity (p = 0.1), gravida (p = 0.1), gestation (p = 0.7), and infant sex (p = 0.1). Predicted IgG titres above the assay lower limit of quantification on day 30 strongly correlated with titres at birth (Spearman correlation coefficient 0.71 [95 % CI: 0.60-0.80]). CONCLUSION: Our results provide a basis for future investigations into the use of antibody kinetics in defining a serocorrelate of protection against late-onset iGBS disease.


Assuntos
Anticorpos Antibacterianos , Imunoglobulina G , Infecções Estreptocócicas , Streptococcus agalactiae , Humanos , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Streptococcus agalactiae/imunologia , Imunoglobulina G/sangue , Lactente , Feminino , Recém-Nascido , Infecções Estreptocócicas/imunologia , Masculino , Reino Unido , Sangue Fetal/imunologia , Estudos de Coortes , Gravidez , Adulto , Sorogrupo , Imunidade Materno-Adquirida
7.
Nat Commun ; 15(1): 3402, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649734

RESUMO

The immune mechanisms mediating COVID-19 vaccine attenuation of COVID-19 remain undescribed. We conducted comprehensive analyses detailing immune responses to SARS-CoV-2 virus in blood post-vaccination with ChAdOx1 nCoV-19 or a placebo. Samples from randomised placebo-controlled trials (NCT04324606 and NCT04400838) were taken at baseline, onset of COVID-19-like symptoms, and 7 days later, confirming COVID-19 using nucleic amplification test (NAAT test) via real-time PCR (RT-PCR). Serum cytokines were measured with multiplexed immunoassays. The transcriptome was analysed with long, short and small RNA sequencing. We found attenuation of RNA inflammatory signatures in ChAdOx1 nCoV-19 compared with placebo vaccinees and reduced levels of serum proteins associated with COVID-19 severity. KREMEN1, a putative alternative SARS-CoV-2 receptor, was downregulated in placebo compared with ChAdOx1 nCoV-19 vaccinees. Vaccination ameliorates reductions in cell counts across leukocyte populations and platelets noted at COVID-19 onset, without inducing potentially deleterious Th2-skewed immune responses. Multi-omics integration links a global reduction in miRNA expression at COVID-19 onset to increased pro-inflammatory responses at the mRNA level. This study reveals insights into the role of COVID-19 vaccines in mitigating disease severity by abrogating pro-inflammatory responses associated with severe COVID-19, affirming vaccine-mediated benefit in breakthrough infection, and highlighting the importance of clinically relevant endpoints in vaccine evaluation.


Assuntos
Infecções Irruptivas , Vacinas contra COVID-19 , COVID-19 , ChAdOx1 nCoV-19 , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , COVID-19/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Citocinas/sangue , Inflamação/imunologia , Multiômica , Transcriptoma , Vacinação
8.
PLoS One ; 19(3): e0290913, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38427691

RESUMO

BACKGROUND: Data on SARS-CoV-2 infection in pregnancy and infancy has accumulated throughout the course of the pandemic, though evidence regarding asymptomatic SARS-CoV-2 infection and adverse birth outcomes are scarce. Limited information is available from countries in sub-Saharan Africa (SSA). The pregnant woman and infant COVID in Africa study (PeriCOVID Africa) is a South-South-North partnership involving hospitals and health centres in five countries: Malawi, Uganda, Mozambique, The Gambia, and Kenya. The study leveraged data from three ongoing prospective cohort studies: Preparing for Group B Streptococcal Vaccines (GBS PREPARE), SARS-CoV-2 infection and COVID-19 in women and their infants in Kampala and Mukono (COMAC) and Pregnancy Care Integrating Translational Science Everywhere (PRECISE). In this paper we describe the seroepidemiology of SARS-CoV-2 infection in pregnant women enrolled in sites in Uganda and Malawi, and the impact of SARS-CoV-2 infection on pregnancy and infant outcomes. OUTCOME: Seroprevalence of SARS-CoV-2 antibodies in maternal blood, reported as the proportion of seropositive women by study site and wave of COVID-19 within each country. METHODS: The PeriCOVID study was a prospective mother-infant cohort study that recruited pregnant women at any gestation antenatally or on the day of delivery. Maternal and cord blood samples were tested for SARS-CoV-2 antibodies using Wantai and Euroimmune ELISA. In periCOVID Uganda and Malawi nose and throat swabs for SARS-Cov-2 RT-PCR were obtained. RESULTS: In total, 1379 women were enrolled, giving birth to 1387 infants. Overall, 63% of pregnant women had a SARS-CoV-2 positive serology. Over subsequent waves (delta and omicron), in the absence of vaccination, seropositivity rose from 20% to over 80%. The placental transfer GMR was 1.7, indicating active placental transfer of anti-spike IgG. There was no association between SARS-CoV-2 antibody positivity and adverse pregnancy or infancy outcomes.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Lactente , Humanos , Feminino , Gravidez , SARS-CoV-2 , Gestantes , COVID-19/epidemiologia , Estudos Prospectivos , Estudos Soroepidemiológicos , Malaui/epidemiologia , Estudos de Coortes , Uganda/epidemiologia , Placenta , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle
9.
Vaccine ; 42(8): 2018-2025, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38395723

RESUMO

BACKGROUND: Previously, the Vi-typhoid conjugate vaccine (Vi-TT) was found to be highly efficacious in Nepalese children under 16 years of age. We assessed the immunogenicity of Vi-TT at 9 and 12 months of age and response to a booster dose at 15 months of age. METHODS: Infants were recruited at Patan Hospital, Kathmandu and received an initial dose of Vi-TT at 9 or 12 months of age with a booster dose at 15 months of age. Blood was taken at four timepoints, and antibody titres were measured using a commercial ELISA kit. The primary study outcome was seroconversion (4-fold rise in antibody titre) of IgG one month after both the doses. FINDINGS: Fifty children were recruited to each study group.Some visits were disrupted by the COVID19 pandemic and occurred out of protocol windows.Both the study groups attained 100 % IgG seroconversion after the initial dose. IgG seroconversion in the 9-month group was significantly higher than in the 12-month group (68.42 % vs 25.8 %, p < 0.001). Among individuals who attended visits per protocol, IgG seroconversion after the first dose occurred in 100 % of individuals (n = 27/27 in 9-month and n = 32/32 in 12-month group). However, seroconversion rates after the second dose were 80 % in the 9-month and 0 % in the shorter dose-interval 12-month group (p < 0.001) (n = 16/20 and n = 0/8, respectively). INTERPRETATION: Vi-TT is highly immunogenic at both 9 and 12 months of age. Stronger response to a booster in the 9-month group is likely due to the longer interval between doses.


Assuntos
Febre Tifoide , Vacinas Tíficas-Paratíficas , Criança , Lactente , Humanos , Febre Tifoide/prevenção & controle , Vacinas Conjugadas , Nepal/epidemiologia , Imunidade , Imunoglobulina G , Anticorpos Antibacterianos , Imunogenicidade da Vacina
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