Neonatal mortality risk of vulnerable newborns by fine stratum of gestational age and birthweight for 230 679 live births in nine low- and middle-income countries, 2000-2017.

OBJECTIVE: To describe the mortality risks by fine strata of gestational age and birthweight among 230 679 live births in nine low- and middle-income countries (LMICs) from 2000 to 2017. DESIGN: Descriptive multi-country secondary data analysis. SETTING: Nine LMICs in sub-Saharan Africa, Southern and Eastern Asia, and Latin America. POPULATION: Liveborn infants from 15 population-based cohorts. METHODS: Subnational, population-based studies with high-quality birth outcome data were invited to join the Vulnerable Newborn Measurement Collaboration. All studies included birthweight, gestational age measured by ultrasound or last menstrual period, infant sex and neonatal survival. We defined adequate birthweight as 2500-3999 g (reference category), macrosomia as ≥4000 g, moderate low as 1500-2499 g and very low birthweight as <1500 g. We analysed fine strata classifications of preterm, term and post-term: ≥42+0 , 39+0 -41+6 (reference category), 37+0 -38+6 , 34+0 -36+6 ,34+0 -36+6 ,32+0 -33+6 , 30+0 -31+6 , 28+0 -29+6 and less than 28 weeks. MAIN OUTCOME MEASURES: Median and interquartile ranges by study for neonatal mortality rates (NMR) and relative risks (RR). We also performed meta-analysis for the relative mortality risks with 95% confidence intervals (CIs) by the fine categories, stratified by regional study setting (sub-Saharan Africa and Southern Asia) and study-level NMR (≤25 versus >25 neonatal deaths per 1000 live births). RESULTS: We found a dose-response relationship between lower gestational ages and birthweights with increasing neonatal mortality risks. The highest NMR and RR were among preterm babies born at <28 weeks (median NMR 359.2 per 1000 live births; RR 18.0, 95% CI 8.6-37.6) and very low birthweight (462.8 per 1000 live births; RR 43.4, 95% CI 29.5-63.9). We found no statistically significant neonatal mortality risk for macrosomia (RR 1.1, 95% CI 0.6-3.0) but a statistically significant risk for all preterm babies, post-term babies (RR 1.3, 95% CI 1.1-1.5) and babies born at 370 -386 weeks (RR 1.2, 95% CI 1.0-1.4). There were no statistically significant differences by region or underlying neonatal mortality. CONCLUSIONS: In addition to tracking vulnerable newborn types, monitoring finer categories of birthweight and gestational age will allow for better understanding of the predictors, interventions and health outcomes for vulnerable newborns. It is imperative that all newborns from live births and stillbirths have an accurate recorded weight and gestational age to track maternal and neonatal health and optimise prevention and care of vulnerable newborns.

Intimate partner violence victimisation and its association with maternal parenting (the 2015 Pelotas [Brazil] Birth Cohort): a prospective cohort study.

BACKGROUND: Intimate partner violence (IPV) is highly prevalent in low-income and middle-income countries and has been a major obstacle towards reaching global health targets for women and children. We aimed to investigate cross-sectional and longitudinal associations between IPV victimisation and maternal parenting practices of young children in a population-based birth cohort study in Brazil. METHODS: The 2015 Pelotas Birth Cohort is an ongoing, prospective cohort, including all hospital births occurring between Jan 1 and Dec 31, 2015, in the city of Pelotas, Brazil. When children were aged 4 years, mothers reported on emotional, physical, and sexual IPV victimisation in the past 12 months. Parenting outcomes were assessed through filming the mother and child in interactive tasks at age 4 years and maternal interviews at ages 4 years and 6-7 years. Interactive tasks were filmed at the Centre for Epidemiological Research facilities. Directly observed outcomes included negative (eg, coercive) and positive (eg, sensitivity and reciprocity) parenting interactions independently coded by a team of psychologists. Self-reported parenting was measured using the subscales on quality of parent-child relationship, positive encouragement, parental consistency, and coercive behaviour of the Parenting and Family Adjustment Scales questionnaire. Unadjusted and adjusted linear regression analyses were performed to assess the associations. FINDINGS: Of the 4275 livebirths enrolled in the cohort, 3730 mother-child dyads were included in our analytical sample at age 4 years and 3292 at age 6-7 years. After adjusting for all potential confounders, emotional IPV and physical or sexual IPV were associated with the following self-reported parenting outcomes: poor parent-child relationship quality (emotional IPV: p=0·011), lower parental consistency (emotional IPV: p<0·001, physical or sexual IPV: p=0·0053), and more coercive behaviour (emotional IPV: p<0·001, physical or sexual IPV: p=0·0071) at age 4 years. Associations were not observed for self-reported positive encouragement and filmed parenting outcomes in fully adjusted models. Longitudinally, IPV at age 4 years predicted similar outcomes when children were aged 6-7 years. INTERPRETATION: In this large cohort study, maternal IPV victimisation was consistently associated with poorer parent-child relationship, decreased parental consistency, and increased harsh parenting reported by mothers of young children. As well as initiatives to prevent IPV, parenting interventions focused on supporting the capacity of caregivers to provide nurturing care delivered at key stages early in the life course are crucial. FUNDING: Wellcome Trust. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.

Quality of vital event data for infant mortality estimation in prospective, population-based studies: an analysis of secondary data from Asia, Africa, and Latin America.

INTRODUCTION: Infant and neonatal mortality estimates are typically derived from retrospective birth histories collected through surveys in countries with unreliable civil registration and vital statistics systems. Yet such data are subject to biases, including under-reporting of deaths and age misreporting, which impact mortality estimates. Prospective population-based cohort studies are an underutilized data source for mortality estimation that may offer strengths that avoid biases. METHODS: We conducted a secondary analysis of data from the Child Health Epidemiology Reference Group, including 11 population-based pregnancy or birth cohort studies, to evaluate the appropriateness of vital event data for mortality estimation. Analyses were descriptive, summarizing study designs, populations, protocols, and internal checks to assess their impact on data quality. We calculated infant and neonatal morality rates and compared patterns with Demographic and Health Survey (DHS) data. RESULTS: Studies yielded 71,760 pregnant women and 85,095 live births. Specific field protocols, especially pregnancy enrollment, limited exclusion criteria, and frequent follow-up visits after delivery, led to higher birth outcome ascertainment and fewer missing deaths. Most studies had low follow-up loss in pregnancy and the first month with little evidence of date heaping. Among studies in Asia and Latin America, neonatal mortality rates (NMR) were similar to DHS, while several studies in Sub-Saharan Africa had lower NMRs than DHS. Infant mortality varied by study and region between sources. CONCLUSIONS: Prospective, population-based cohort studies following rigorous protocols can yield high-quality vital event data to improve characterization of detailed mortality patterns of infants in low- and middle-income countries, especially in the early neonatal period where mortality risk is highest and changes rapidly.

Neonatal mortality risk of vulnerable newborns: A descriptive analysis of subnational, population-based birth cohorts for 238 203 live births in low- and middle-income settings from 2000 to 2017.

OBJECTIVE: We aimed to understand the mortality risks of vulnerable newborns (defined as preterm and/or born weighing smaller or larger compared to a standard population), in low- and middle-income countries (LMICs). DESIGN: Descriptive multi-country, secondary analysis of individual-level study data of babies born since 2000. SETTING: Sixteen subnational, population-based studies from nine LMICs in sub-Saharan Africa, Southern and Eastern Asia, and Latin America. POPULATION: Live birth neonates. METHODS: We categorically defined five vulnerable newborn types based on size (large- or appropriate- or small-for-gestational age [LGA, AGA, SGA]), and term (T) and preterm (PT): T + LGA, T + SGA, PT + LGA, PT + AGA, and PT + SGA, with T + AGA (reference). A 10-type definition included low birthweight (LBW) and non-LBW, and a four-type definition collapsed AGA/LGA into one category. We performed imputation for missing birthweights in 13 of the studies. MAIN OUTCOME MEASURES: Median and interquartile ranges by study for the prevalence, mortality rates and relative mortality risks for the four, six and ten type classification. RESULTS: There were 238 203 live births with known neonatal status. Four of the six types had higher mortality risk: T + SGA (median relative risk [RR] 2.6, interquartile range [IQR] 2.0-2.9), PT + LGA (median RR 7.3, IQR 2.3-10.4), PT + AGA (median RR 6.0, IQR 4.4-13.2) and PT + SGA (median RR 10.4, IQR 8.6-13.9). T + SGA, PT + LGA and PT + AGA babies who were LBW, had higher risk compared with non-LBW babies. CONCLUSIONS: Small and/or preterm babies in LIMCs have a considerably increased mortality risk compared with babies born at term and larger. This classification system may advance the understanding of the social determinants and biomedical risk factors along with improved treatment that is critical for newborn health.

Breastfeeding Duration and Exclusivity Among Early-Term and Full-Term Infants: A Cohort Study.

Background: As compared to full-term infants (39-41 weeks of gestation), early-term infants (37-38 wk) are at increased risk of adverse outcomes, including shorter exclusive breastfeeding (EB) duration and continued breastfeeding. Objectives: To compare early-term with full- and late-term infants regarding the prevalence of EB at 3 mo and any breastfeeding at 12 mo. Methods: Data sets from two population-based birth cohorts conducted in the city of Pelotas, Brazil, were combined. Only term infants (37 0/7 through 41 6/7 weeks of gestation) were included in the analyses. Early-term infants (37 0/7 through 38 6/7 wk) were compared to the remaining term infants (39 0/7 through 41 6/7 wk). Information on breastfeeding was gathered through maternal interviews at the 3-mo and 12-mo follow-ups. The prevalence of EB at 3 mo and any breastfeeding at 12 mo with 95% CIs were calculated. Crude and adjusted prevalence ratios (PRs) were obtained through Poisson regression. Results: A total of 6395 infants with information on gestational age and EB at 3 mo and 6401 infants with information on gestational age and any breastfeeding at 12 mo were analyzed. There was no difference between early-term infants and the remaining term infants regarding the prevalence of EB at 3 mo (29.2% and 27.9%, respectively) (P = 0.248). Prevalence of any breastfeeding at 12 mo was lower in early-term infants than among those born between 39 0/7 and 41 6/7 weeks of gestation (38.2% compared with 42.4%) (P = 0.001). In the adjusted analysis, the PR for any breastfeeding at 12 mo was 15% lower in the early-term group than in the remaining term infants (PR = 0.85; 95% CI: 0.76-0.95) (P = 0.004). Conclusions: The prevalence of EB at 3 mo was similar among term infants. Nonetheless, in comparison with the remaining infants born at term, early-term infants were at increased risk of having been weaned before reaching 12 mo of age. Curr Dev Nutr 2023;xx:xx.

Child and Maternal Mental Health Before and During the COVID-19 Pandemic: Longitudinal Social Inequalities in a Brazilian Birth Cohort.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has caused major stress for families and children, particularly in the context of prolonged school closures. Few longitudinal studies are available on young children's mental health, including data both before and during the pandemic. This study examined experiences that might increase risk for mental health problems among caregivers and young children during the COVID-19 pandemic and inequalities driven by pre-pandemic disadvantage. METHOD: This prospective, population-based birth cohort study in Pelotas, Brazil, analyzed 2,083 children and caregivers with data from before the pandemic in 2019, when children were 4 years old, and again in 2020, when schools were closed for a long period during the pandemic. Child conduct problems, emotional problems, and hyperactivity-inattention problems were assessed using the Strengths and Difficulties Questionnaire. Family financial hardship, relationship difficulties, caregiver mental health, parenting practices, and child fears and isolation were considered as potential risk factors. RESULTS: Across the whole population, the only significant increase in mental health problems from before to during the pandemic was found for maternal depression. However, poorer families were at far greater risk of experiencing serious financial problems, food shortages, increased conflict in adult relationships, parenting problems, and child worries about food availability during the pandemic. In turn, these difficulties were associated with increases in multiple mental health problems for both caregivers and children. Increased child mental health problems were most strongly associated with concurrent maternal anxiety (ß > 0.20, p < .001, for each of child conduct, emotional, and hyperactivity problems), maternal depression (ß = 0.26, p < .001, for child emotional problems), partner criticism (ß = 0.21, p < .001, for child conduct problems), and harsh parenting (ß > 0.20, p < .001, for both child conduct and hyperactivity problems). Child worry about COVID-19 was associated with increased emotional problems (ß = 0.14, p < .001), but children's isolation was not associated with their mental health. CONCLUSION: Overall, the impact of the COVID-19 pandemic on mental health is a mixed picture, but for families in poverty, marked material and interpersonal difficulties were associated with increases in mental health problems among children and caregivers.

Construction and validation of the Oxford Neurodevelopment Assessment (OX-NDA) in 1-year-old Brazilian children.

BACKGROUND: Over 250 million children under 5 years, globally, are at risk of developmental delay. Interventions during the first 2 years of life have enduring positive effects if children at risk are identified, using standardized assessments, within this window. However, identifying developmental delay during infancy is challenging and there are limited infant development assessments suitable for use in low- and middle-income (LMIC) settings. Here, we describe a new tool, the Oxford Neurodevelopment Assessment (OX-NDA), measuring cognition, language, motor, and behaviour, outcomes in 1-year-old children. We present the results of its evaluation against the Bayley Scales of Infant Development IIIrd edition (BSID-III) and its psychometric properties. METHODS: Sixteen international tools measuring infant development were analysed to inform the OX-NDA's construction. Its agreement with the BSID-III, for cognitive, motor and language domains, was evaluated using intra-class correlations (ICCs, for absolute agreement), Bland-Altman analyses (for bias and limits of agreement), and sensitivity and specificity analyses (for accuracy) in 104 Brazilian children, aged 12 months (SD 8.4 days), recruited from the 2015 Pelotas Birth Cohort Study. Behaviour was not evaluated, as the BSID-III's adaptive behaviour scale was not included in the cohort's protocol. Cohen's kappas and Cronbach's alphas were calculated to determine the OX-NDA's reliability and internal consistency respectively. RESULTS: Agreement was moderate for cognition and motor outcomes (ICCs 0.63 and 0.68, p < 0.001) and low for language outcomes (ICC 0.30, p < 0.04). Bland-Altman analysis showed little to no bias between measures across domains. The OX-NDA's sensitivity and specificity for predicting moderate-to-severe delay on the BSID-III was 76, 73 and 43% and 75, 80 and 33% for cognition, motor and language outcomes, respectively. Inter-rater (k = 0.80-0.96) and test-rest (k = 0.85-0.94) reliability was high for all domains. Administration time was < 20 minutes. CONCLUSION: The OX-NDA shows moderate agreement with the BSID-III for identifying infants at risk of cognitive and motor delay; agreement was low for language delay. It is a rapid, low-cost assessment constructed specifically for use in LMIC populations. Further work is needed to evaluate its use (i) across domains in populations beyond Brazil and (ii) to identify language delays in Brazilian children.

Prevalence and predictors of anti-SARS-CoV-2 serology in a highly vulnerable population of Rio de Janeiro: A population-based serosurvey.

Background: COVID-19 serosurveys allow for the monitoring of the level of SARS-CoV-2 transmission and support data-driven decisions. We estimated the seroprevalence of anti-SARS-CoV-2 antibodies in a large favela complex in Rio de Janeiro, Brazil. Methods: A population-based panel study was conducted in Complexo de Manguinhos (16 favelas) with a probabilistic sampling of participants aged ≥1 year who were randomly selected from a census of individuals registered in primary health care clinics that serve the area. Participants answered a structured interview and provided blood samples for serology. Multilevel regression models (with random intercepts to account for participants' favela of residence) were used to assess factors associated with having anti-S IgG antibodies. Secondary analyses estimated seroprevalence using an additional anti-N IgG assay. Findings: 4,033 participants were included (from Sep/2020 to Feb/2021, 22 epidemic weeks), the median age was 39·8 years (IQR:21·8-57·7), 61% were female, 41% were mixed-race (Pardo) and 23% Black. Overall prevalence was 49·0% (95%CI:46·8%-51·2%) which varied across favelas (from 68·3% to 31·4%). Lower prevalence estimates were found when using the anti-N IgG assay. Odds of having anti-S IgG antibodies were highest for young adults, and those reporting larger household size, poor adherence to social distancing and use of public transportation. Interpretation: We found a significantly higher prevalence of anti-S IgG antibodies than initially anticipated. Disparities in estimates obtained using different serological assays highlight the need for cautious interpretation of serosurveys estimates given the heterogeneity of exposure in communities, loss of immunological biomarkers, serological antigen target, and variant-specific test affinity. Funding: Fundação Oswaldo Cruz, Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ), the European Union's Horizon 2020 research and innovation programme, Royal Society, Serrapilheira Institute, and FAPESP.

COVID-19 and outpatient care: a nationwide household survey.

We aimed to assess the proportion of the population in 133 Brazilian municipalities who - from March to August 2020 - had a health problem but failed to seek care or failed to attend to a health service for routine appointment or examination. We conducted a household survey from August 24-27 in 133 Brazilian cities by asking the subjects if, since the beginning of the COVID-19 pandemic in March 2020, they had suffered from a health problem but did not seek care or failed to attend to a routine or screening examination. Poisson regression was used for the analyses. We interviewed 33,250 subjects and 11.8% (95%CI: 11.4-12.1) reported that, since March 2020, they failed to seek care despite being ill, 17.3% (95%CI: 16.9-17.7) failed to attend to a routine or screening examination and 23.9% (95%CI: 23.4-24.4) reported one or both outcomes. Health service closure and fear of the COVID-19 infection were the main reasons for not seeking care. Women and the poorest were more likely to not look for a health service, despite having a health problem or a scheduled routine appointment. On the other hand, those subjects who self-identified as white were less likely to not look for a health service. The COVID-19 pandemic is more critical for the indigenous people and the poorest, and these people are also more likely to not seek care for other health conditions during the pandemic.

COVID-19 and outpatient care: a nationwide household survey / COVID-19 e assistência ambulatorial: uma pesquisa domiciliar de abrangência nacional / COVID-19 y atención ambulatoria: una encuesta domiciliaria a escala nacional

We aimed to assess the proportion of the population in 133 Brazilian municipalities who - from March to August 2020 - had a health problem but failed to seek care or failed to attend to a health service for routine appointment or examination. We conducted a household survey from August 24-27 in 133 Brazilian cities by asking the subjects if, since the beginning of the COVID-19 pandemic in March 2020, they had suffered from a health problem but did not seek care or failed to attend to a routine or screening examination. Poisson regression was used for the analyses. We interviewed 33,250 subjects and 11.8% (95%CI: 11.4-12.1) reported that, since March 2020, they failed to seek care despite being ill, 17.3% (95%CI: 16.9-17.7) failed to attend to a routine or screening examination and 23.9% (95%CI: 23.4-24.4) reported one or both outcomes. Health service closure and fear of the COVID-19 infection were the main reasons for not seeking care. Women and the poorest were more likely to not look for a health service, despite having a health problem or a scheduled routine appointment. On the other hand, those subjects who self-identified as white were less likely to not look for a health service. The COVID-19 pandemic is more critical for the indigenous people and the poorest, and these people are also more likely to not seek care for other health conditions during the pandemic.

O estudo teve como objetivo avaliar a proporção da população de 133 cidades brasileiras que apresentou algum problema de saúde entre março e agosto de 2020, mas que deixou de procurar atendimento, ou que deixou de buscar um serviço de saúde para consultas ou exames de rotina. Foram realizadas entrevistas domiciliares entre 24 e 27 de agosto de 2020 em 133 áreas urbanas brasileiras. Perguntava-se aos indivíduos se, desde o início da pandemia de COVID-19 em março de 2020, haviam sofrido algum problema de saúde mais não haviam procurado atendimento, ou se haviam deixado de realizar consultas ou exames de rotina. A regressão de Poisson foi utilizada para as análises. Foram entrevistados 33.250 indivíduos, entre os quais 11,8% (IC95%: 11,4-12,1) relataram que desde março de 2020 haviam deixado de procurar atendimento apesar de estarem doentes, 17,3% (IC95%: 16,9-17,7) haviam deixado de comparecer a consultas de rotina ou triagem e 23,9% (IC95%: 23,4-24,4) relataram um ou ambos os desfechos. O fechamento dos serviços de saúde e o medo da infecção pelo SARS-CoV-2 foram os principais motivos para não buscar atendimento. As mulheres e os indivíduos com menor nível socioeconômico mostraram maior probabilidade de não procurarem serviços de saúde em caso de doença, ou de faltar a consultas de rotina previamente agendadas. Por outro lado, indivíduos que se identificavam como brancos eram menos propensos a deixar de procurar os serviços de saúde. A pandemia da COVID-19 está afetando mais duramente os indígenas e as pessoas com menor nível socioeconômico, que também são mais propensos a deixar de procurar atendimento para outras condições de saúde durante a pandemia.

Se realizó un estudio con el fin de evaluar la proporción de población en 133 ciudades brasileñas que -de marzo a agosto 2020- tuvieron un problema de salud, pero no consiguieron buscar cuidados, o presentarse en un servicio de salud para consultas de rutina o exámenes. Se llevó a cabo una encuesta domiciliaria entre el 24 y 27 de agosto en 133 áreas urbanas brasileñas. A los encuestados se les preguntó si, desde el principio de la pandemia de COVID-19 en marzo de 2020, habían sufrido algún problema de salud, pero no habían buscado asistencia, o no consiguieron presentarse a exámenes de rutina o de exploración. Se utilizó una regresión de Poisson para los análisis. Se entrevistó a 33.250 individuos, y un 11,8% (IC95%: 11,4-12,1) informaron que desde marzo de 2020 no consiguieron buscar asistencia, a pesar de estar enfermos, un 17,3% (IC95%: 16,9-17,7) no consiguieron presentarse a exámenes de rutina o visitas de exploración, y un 23,9% (IC95%: 23,4-24,4) informaron de uno o ambos resultados. El cierre de los servicios de salud y el miedo a contraer COVID-19 fueron las razones principales para no buscar cuidados. Las mujeres y aquellos que tenían un estatus socioeconómico bajo eran más propensos a no buscar asistencia sanitaria, tanto si tenían un problema médico, como para un chequeo rutinario o se saltaban una cita médica programada. Por otro lado, estas personas que se autoidentificaron como blancas eran menos propensas a no buscar asistencia sanitaria. La pandemia de COVID-19 está golpeando duramente a los indígenas y a quienes tienen un estatus socioeconómico bajo, y estas personas también son más propensas a no conseguir buscar asistencia sanitaria relacionada con otros problemas de salud durante la pandemia.

Population-level seropositivity trend for SARS-Cov-2 in Rio Grande do Sul, Brazil.

OBJECTIVE: To describe the evolution of seropositivity in the State of Rio Grande do Sul, Brazil, through 10 consecutive surveys conducted between April 2020 and April 2021. METHODS: Nine cities covering all regions of the State were studied, 500 households in each city. One resident in each household was randomly selected for testing. In survey rounds 1-8 we used the rapid WONDFO SARS-CoV-2 Antibody Test (Wondfo Biotech Co., Guangzhou, China). In rounds 9-10, we used a direct ELISA test that identifies IgG to the viral S protein (S-UFRJ). In terms of social distancing, individuals were asked three questions, from which we generated an exposure score using principal components analysis. RESULTS: Antibody prevalence in early April 2020 was 0.07%, increasing to 10.0% in February 2021, and to 18.2% in April 2021. In round 10, self-reported whites showed the lowest seroprevalence (17.3%), while indigenous individuals presented the highest (44.4%). Seropositivity increased by 40% when comparing the most with the least exposed. CONCLUSIONS: The proportion of the population already infected by SARS-Cov-2 in the state is still far from any perspective of herd immunity and the infection affects population groups in very different levels.

[Prevalence of antibodies against SARS-CoV-2 according to socioeconomic and ethnic status in a nationwide Brazilian surveyPrevalência de anticorpos contra o SARS-CoV-2 de acordo com o status socioeconômico e étnico em uma pesquisa nacional no Brasil]. / Prevalencia de anticuerpos contra el SARS-CoV-2 según el estatus socioeconómico y étnico en una encuesta nacional de Brasil.

OBJECTIVES: To investigate socioeconomic and ethnic group inequalities in prevalence of antibodies against SARS-CoV-2 in the 27 federative units of Brazil. METHODS: In this cross-sectional study, three household surveys were carried out on May 14-21, June 4-7, and June 21-24, 2020 in 133 Brazilian urban areas. Multi-stage sampling was used to select 250 individuals in each city to undergo a rapid antibody test. Subjects answered a questionnaire on household assets, schooling and self-reported skin color/ethnicity using the standard Brazilian classification in five categories: white, black, brown, Asian or indigenous. Principal component analyses of assets was used to classify socioeconomic position into five wealth quintiles. Poisson regression was used for the analyses. RESULTS: 25 025 subjects were tested in the first, 31 165 in the second, and 33 207 in the third wave of the survey, with prevalence of positive results equal to 1.4%, 2.4%, and 2.9% respectively. Individuals in the poorest quintile were 2.16 times (95% confidence interval 1.86; 2.51) more likely to test positive than those in the wealthiest quintile, and those with 12 or more years of schooling had lower prevalence than subjects with less education. Indigenous individuals had 4.71 (3.65; 6.08) times higher prevalence than whites, as did those with black or brown skin color. Adjustment for region of the country reduced the prevalence ratios according to wealth, education and ethnicity, but results remained statistically significant. CONCLUSIONS: The prevalence of antibodies against SARS-CoV-2 in Brazil shows steep class and ethnic gradients, with lowest risks among white, educated and wealthy individuals.

OBJETIVOS: Investigar as desigualdades socioeconômicas e étnicas na prevalência de anticorpos contra SARS-CoV-2 nas 27 unidades federativas do Brasil. MÉTODOS: Neste estudo transversal, três pesquisas domiciliares foram realizadas de 14 a 21 de maio, 4 a 7 de junho, e 21-24 de junho, 2020 em 133 áreas urbanas brasileiras. Amostragem em várias etapas foi utilizada para selecionar 250 indivíduos em cada cidade para se submeter a um teste rápido de anticorpos. Os sujeitos responderam a um questionário sobre bens domésticos, escolaridade e cor da pele/etnicidade (auto-relatada utilizando a classificação padrão brasileira de cinco categorias: branco, preto, pardo, asiático ou indígena). A análise dos componentes principais dos ativos foi utilizada para classificar a posição socioeconómica em cinco quintis de riqueza. A regressão de Poisson foi utilizada para as análises. RESULTADOS: 25 025 indivíduos foram testados na primeira pesquisa, 31 165 na segunda, e 33 207 na terceira, com prevalência de resultados positivos de 1,4%, 2,4% e 2,9%, respectivamente. Indivíduos no quintil mais pobre tinham 2,16 vezes (intervalo de confiança de 95% 1,86; 2,51) mais probabilidade de ter um resultado positivo do que aqueles do quintil mais rico, e aqueles com 12 ou mais anos de escolaridade tinham uma prevalência menor do que aqueles com menos educação. Os indivíduos indígenas tinham 4,71 (3,65; 6,08) vezes mais prevalência do que os brancos, assim como aqueles com cor da pele preta ou parda. O ajuste regional reduziu as taxas de prevalência de acordo com a riqueza, educação e etnia, mas os resultados permaneceram estatisticamente significativos. CONCLUSÕES: A prevalência de anticorpos contra a SARS-CoV-2 no Brasil mostra gradientes relacionados com a posição socioeconómica e a etnia muito acentuados, com os menores riscos entre os indivíduos brancos, educados e ricos.

Prevalencia de anticuerpos contra el SARS-CoV-2 según el estatus socioeconómico y étnico en una encuesta nacional de Brasil

[RESUMEN]. Objetivos. Investigar las desigualdades socioeconómicas y entre distintos grupos étnicos en la prevalencia de anticuerpos contra el SARS-CoV-2 en las 27 unidades federativas de Brasil. Métodos. En este estudio transversal, se realizaron tres encuestas de hogares los días 14-21 de mayo, 4-7 de junio y 21-24 de junio de 2020 en 133 áreas urbanas brasileñas. Se utilizó un muestreo de etapas múltiples para seleccionar 250 individuos en cada ciudad a fin de someterlos a una prueba rápida de anticuerpos. Los sujetos respondieron un cuestionario sobre los bienes del hogar, la escolaridad y el color de la piel y etnia (autodeclarado utilizando la clasificación brasileña estándar de cinco categorías: blanco, negro, pardo, asiático o indígena). Se utilizó el análisis de los componentes principales de los bienes para clasificar el estatus socioeconómico en cinco quintiles de riqueza. Se empleó la regresión de Poisson para los análisis. Resultados. Se analizaron 25 025 sujetos en la primera encuesta, 31 165 en la segunda y 33 207 en la tercera, que mostraron una prevalencia de resultados positivos de 1,4%, 2,4% y 2,9%; respectivamente. Los individuos del quintil más pobre tuvieron 2,16 veces más probabilidades de presentar un resultado positivo (intervalo de confianza del 95%: 1,86-2,51) que los del quintil más rico, y los que tenían 12 o más años de escolaridad tuvieron una prevalencia menor que los sujetos con menos educación. Las personas indígenas presentaron una prevalencia 4,71 (IC95%: 3,65-6,08) veces mayor que las blancas, al igual que las de piel negra o parda. El ajuste por región del país redujo los índices de prevalencia según la riqueza, la educación y el origen étnico, pero los resultados siguieron siendo estadísticamente significativos. Conclusiones. La prevalencia de anticuerpos contra el SARS-CoV-2 en Brasil muestra gradientes relacionados con la posición socioeconómica y la etnia muy pronunciados, con menor riesgo en las personas blancas, educadas y ricas.

[ABSTRACT]. Objectives. To investigate socioeconomic and ethnic group inequalities in prevalence of antibodies against SARS-CoV-2 in the 27 federative units of Brazil. Methods. In this cross-sectional study, three household surveys were carried out on May 14-21, June 4-7, and June 21-24, 2020 in 133 Brazilian urban areas. Multi-stage sampling was used to select 250 individuals in each city to undergo a rapid antibody test. Subjects answered a questionnaire on household assets, schooling and self-reported skin color/ethnicity using the standard Brazilian classification in five categories: white, black, brown, Asian or indigenous. Principal component analyses of assets was used to classify socioeconomic position into five wealth quintiles. Poisson regression was used for the analyses. Results. 25 025 subjects were tested in the first, 31 165 in the second, and 33 207 in the third wave of the survey, with prevalence of positive results equal to 1.4%, 2.4%, and 2.9% respectively. Individuals in the poorest quintile were 2.16 times (95% confidence interval 1.86; 2.51) more likely to test positive than those in the wealthiest quintile, and those with 12 or more years of schooling had lower prevalence than subjects with less education. Indigenous individuals had 4.71 (3.65; 6.08) times higher prevalence than whites, as did those with black or brown skin color. Adjustment for region of the country reduced the prevalence ratios according to wealth, education and ethnicity, but results remained statistically significant. Conclusions. The prevalence of antibodies against SARS-CoV-2 in Brazil shows steep class and ethnic gradients, with lowest risks among white, educated and wealthy individuals.

[RESUMO]. Objetivos. Investigar as desigualdades socioeconômicas e étnicas na prevalência de anticorpos contra SARS-CoV-2 nas 27 unidades federativas do Brasil. Métodos. Neste estudo transversal, três pesquisas domiciliares foram realizadas de 14 a 21 de maio, 4 a 7 de junho, e 21-24 de junho, 2020 em 133 áreas urbanas brasileiras. Amostragem em várias etapas foi utilizada para selecionar 250 indivíduos em cada cidade para se submeter a um teste rápido de anticorpos. Os sujeitos responderam a um questionário sobre bens domésticos, escolaridade e cor da pele/etnicidade (auto-relatada utilizando a classificação padrão brasileira de cinco categorias: branco, preto, pardo, asiático ou indígena). A análise dos componentes principais dos ativos foi utilizada para classificar a posição socioeconómica em cinco quintis de riqueza. A regressão de Poisson foi utilizada para as análises. Resultados. 25 025 indivíduos foram testados na primeira pesquisa, 31 165 na segunda, e 33 207 na terceira, com prevalência de resultados positivos de 1,4%, 2,4% e 2,9%, respectivamente. Indivíduos no quintil mais pobre tinham 2,16 vezes (intervalo de confiança de 95% 1,86; 2,51) mais probabilidade de ter um resultado positivo do que aqueles do quintil mais rico, e aqueles com 12 ou mais anos de escolaridade tinham uma prevalência menor do que aqueles com menos educação. Os indivíduos indígenas tinham 4,71 (3,65; 6,08) vezes mais prevalência do que os brancos, assim como aqueles com cor da pele preta ou parda. O ajuste regional reduziu as taxas de prevalência de acordo com a riqueza, educação e etnia, mas os resultados permaneceram estatisticamente significativos. Conclusões. A prevalência de anticorpos contra a SARS-CoV-2 no Brasil mostra gradientes relacionados com a posição socioeconómica e a etnia muito acentuados, com os menores riscos entre os indivíduos brancos, educados e ricos.

Characteristics and outcomes of pregnant women with SARS-CoV-2 infection and other severe acute respiratory infections (SARI) in Brazil from January to November 2020.

BACKGROUND: Knowledge about COVID-19 in pregnancy is limited, and evidence on the impact of the infection during pregnancy and postpartum is still emerging. AIM: To analyze maternal morbidity and mortality due to severe acute respiratory infections (SARI), including COVID-19, in Brazil. METHODS: National surveillance data from the SIVEP-Gripe (Sistema de Informação de Vigilância Epidemiológica da Gripe) was used to describe currently and recently pregnant women aged 10-49 years hospitalized for SARI from January through November, 2020. SARI cases were grouped into: COVID-19; influenza or other detected agent SARI; and SARI of unknown etiology. Characteristics, symptoms and outcomes were presented by SARI type and region. Binomial proportion and 95% confidence intervals (95% CI) for outcomes were obtained using the Clopper-Pearson method. RESULTS: Of 945,460 SARI cases in the SIVEP-Gripe, we selected 11,074 women aged 10-49 who were pregnant (7964) or recently pregnant (3110). COVID-19 was confirmed in 49.4% cases; 1.7% had influenza or another etiological agent; and 48.9% had SARI of unknown etiology. The pardo race/ethnic group accounted for 50% of SARI cases. Hypertension/Other cardiovascular diseases, chronic respiratory diseases, diabetes, and obesity were the most common comorbidities. A total of 362 women with COVID-19 (6.6%; 95%CI 6.0-7.3) died. Mortality was 4.7% (2.2-8.8) among influenza patients, and 3.3% (2.9-3.8) among those with SARI of unknown etiology. The South-East, Northeast and North regions recorded the highest frequencies of mortality among COVID-19 patients. CONCLUSION: Mortality among pregnant and recently pregnant women with SARIs was elevated among those with COVID-19, particularly in regions where maternal mortality is already high.

Time-dependent decay of detectable antibodies against SARS-CoV-2: A comparison of ELISA with two batches of a lateral-flow test.

BACKGROUND: Large-scale epidemiological studies of seroprevalence of antibodies against SARS-CoV-2 often rely on point-of-care tests that provide immediate results to participants. Yet, little is known on how long rapid tests remain positive after the COVID-19 episode, or how much variability exists across different brands and even among batches of the same test. METHODS: In November 2020, we assessed the sensitivity of three tests applied to 133 individuals with a previous positive PCR result between April and October. All subjects provided finger prick blood samples for two batches (A and B) of the Wondfo lateral-flow IgG/IgM test, and dried blood spot samples for the S-UFRJ ELISA test. RESULTS: Overall sensitivity levels were 92.5% (95% CI 86.6-96.3), 63.2% (95% CI 54.4-71.4) and 33.8% (95% CI 25.9-42.5) for the S-UFRJ test, Wondfo A and Wondfo B tests, respectively. There was no evidence of a decline in the positivity of S-UFRJ with time since the diagnosis, but the two Wondfo batches showed sharp reductions to as low as 41.9% and 19.4%, respectively, for subjects with a positive PCR in June or earlier. Positive results for batch B of the rapid test were 35% to 54% lower than for batch A at any given month of diagnosis. INTERPRETATION: Whereas the ELISA test showed high sensitivity and stability of results over the five months of the study, both batches of the rapid test showed substantial declines, with one of the batches consistently showing lower sensitivity levels than the other. ELISA tests based on dried-blood spots are an inexpensive alternative to rapid lateral-flow tests in large-scale epidemiological studies. FUNDING: The study was funded by the "Todos Pela Saúde" initiative, Instituto Serrapilheira, Brazilian Ministry of Health, Brazilian Collective Health Association (ABRASCO) and the JBS S.A. initiative 'Fazer o Bem Faz Bem'.

Slow Spread of SARS-CoV-2 in Southern Brazil Over a 6-Month Period: Report on 8 Sequential Statewide Serological Surveys Including 35 611 Participants.

Objectives. To evaluate the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) over 6 months in the Brazilian State of Rio Grande do Sul (population 11.3 million), based on 8 serological surveys. Methods. In each survey, 4151 participants in round 1 and 4460 participants in round 2 were randomly sampled from all state regions. We assessed presence of antibodies against SARS-CoV-2 using a validated lateral flow point-of-care test; we adjusted figures for the time-dependent decay of antibodies. Results. The SARS-CoV-2 antibody prevalence increased from 0.03% (95% confidence interval [CI] = 0.00%, 0.34%; 1 in every 3333 individuals) in mid-April to 1.89% (95% CI = 1.36%, 2.54%; 1 in every 53 individuals) in early September. Prevalence was similar across gender and skin color categories. Older adults were less likely to be infected than younger participants. The proportion of the population who reported leaving home daily increased from 21.4% (95% CI = 20.2%, 22.7%) to 33.2% (95% CI = 31.8%, 34.5%). Conclusions. SARS-CoV-2 infection increased slowly during the first 6 months in the state, differently from what was observed in other Brazilian regions. Future survey rounds will continue to document the spread of the pandemic.

COVID-19 and social distancing among children and adolescents in Brazil.

OBJECTIVE: To estimate the prevalence of SARS-CoV-2 antibodies and the adherence to measures of social distancing in children and adolescents studied in three national surveys conducted in Brazil between May-June 2020. METHODS: Three national serological surveys were conducted in 133 sentinel cities located in all 27 Federative Units. Multistage probability sampling was used to select 250 individuals per city. The total sample size in age ranges 0-9 and 10-19 years old are of 4,263 and 8,024 individuals, respectively. Information on children or adolescents was gathered with a data collection app, and a rapid point-of-case test for SARS-CoV-2 was conducted on a finger prick blood sample. RESULTS: The adjusted prevalence of antibodies was 2.9% (2.2-3.6) among children 0-9 years, 2.2% (1.8-2.6) among adolescents 10-19 years, and 3.0% (2.7-3.3) among adults 20+years. Prevalence of antibodies was higher among poor children and adolescents compared to those of rich families. Adherence to social distancing measures was seen in 72.4% (71.9-73.8) of families with children, 60.8% (59.6-61.9) for adolescents, and 57.4% (56.9-57.8) for adults. For not leaving the house except for essential matters the proportions were 81.7% (80.5-82.9), 70.6% (69.6-61.9), and 65.1% (64.7-65.5), respectively. Among children and adolescents, social distancing was strongly associated with socioeconomic status, being much higher in the better-off families. CONCLUSIONS: The prevalence of antibodies against SARS-CoV-2 showed comparable levels among children, adolescents, and adults. Adherence to social distancing measures was more prevalent in children, followed by adolescents. There were important socioeconomic differences in the adherence to social distancing among children and adolescents.

High prevalence of symptoms among Brazilian subjects with antibodies against SARS-CoV-2.

Since the beginning of the pandemic of COVID-19, there has been a widespread assumption that most infected persons are asymptomatic. Using data from the recent wave of the EPICOVID19 study, a nationwide household-based survey including 133 cities from all states of Brazil, we estimated the proportion of people with and without antibodies for SARS-CoV-2 who were asymptomatic, which symptoms were most frequently reported, number of symptoms and the association with socio-demographic characteristics. We tested 33,205 subjects using a rapid antibody test previously validated. Information was collected before participants received the test result. Out of 849 (2.7%) participants positive for SARS-CoV-2 antibodies, only 12.1% (95% CI 10.1-14.5) reported no symptoms, compared to 42.2% (95% CI 41.7-42.8) among those negative. The largest difference between the two groups was observed for changes in smell/taste (56.5% versus 9.1%, a 6.2-fold difference). Changes in smell/taste, fever and body aches were most likely to predict positive tests as suggested by recursive partitioning tree analysis. Among individuals without any of these three symptoms, only 0.8% tested positive, compared to 18.3% of those with both fever and changes in smell or taste. Most subjects with antibodies against SARS-CoV-2 are symptomatic, even though most present only mild symptoms.

Missed childhood immunizations during the COVID-19 pandemic in Brazil: Analyses of routine statistics and of a national household survey.

INTRODUCTION: There is widespread concern that disruption to health services during the COVID-19 pandemic has led to declines in immunization coverage among young children, but there is limited information on the magnitude of such impact. High immunization coverage is essential for reducing the risk of vaccine preventable diseases. METHODS: We used data from two nationwide sources covering the whole of Brazil. Data from the Information System of the National Immunization Program (SIPNI) on the monthly number of vaccine doses administered to young children were analyzed. The second source was a survey in 133 large cities in the 27 states in the country, carried out from August 24-27. Respondents answered a question on whether children under the age of three years had missed any scheduled vaccinations during the pandemic, and available vaccination cards were photographed for later examination. RESULTS: SIPNI data showed that, relative to January and February 2020, there was a decline of about 20% in vaccines administered to children aged two months or older during March and April, when social distancing was at the highest level in the country. After May, vaccination levels returned to pre-pandemic values. Survey data, based on the interviews and on examination of the vaccine cards, showed that 19.0% (95% CI 17.0;21.1%) and 20.6% (95% CI 19.0;23.1%) of children, respectively, had missed immunizations. Missed doses were most common in the North (Amazon) region and least common in the South and Southeast, and also more common among children from poor than from wealthy families. INTERPRETATION: Our results show that the pandemic was associated with a reduction of about 20% in child vaccinations, but this was reverted in recent months. Children from poor families and from the least developed regions of the country were most affected. There is an urgent need to booster immunization activities in the country to compensate for missed doses, and to reduce geographic and socioeconomic inequalities.