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Factors associated with small- and large-for-gestational-age in socioeconomically vulnerable individuals in the 100 million brazilian cohort
No full textMCTI/CNPq/MS/SCTIE/Decit/Bill & Melinda
Gates Foundation’s Grandes Desafios Brasil—Desenvolvimento Saudável
para Todas as Crianças (call number 47/2014). CIDACS and the 100 Million
Cohort received core support from the Wellcome Trust (grant number
202912/Z/16/Z); Health Surveillance Secretariat, Ministry of Health, Brazil,
Bahia State; Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB);
Financiadora de Estudos e Projetos-FINEP, Secretariat of Science and
Technology of the State of Bahia-SECTI. IRF received a doctoral scholarship
from Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB) (grant
number BOL2330 / 2016). ESP is a fellow supported by the Wellcome Trust
(grant number 213589/Z/18/Z).Background: Evidence points to diverse risk factors associated with small- (SGA) and large-for-gestational-age (LGA) births. A more comprehensive understanding of these factors is imperative, especially in vulnerable populations. Objectives: To estimate the occurrence of and sociodemographic factors associated with SGA and LGA births in poor and extremely poor populations of Brazil. Methods: The study population consisted of women of reproductive age (14–49 y), whose last child was born between 2012 and 2015. INTERGROWTH 21st consortium criteria were used to classify weight for gestational age according to sex. Multinomial logistic regression modeling was performed to investigate associations of interest. Results: Of 5,521,517 live births analyzed, SGA and LGA corresponded to 7.8% and 17.1%, respectively. Multivariate analysis revealed greater odds of SGA in children born to women who selfreported as black (OR: 1.21; 95% CI: 1.19, 1.22), mixed-race (parda) (OR: 1.08; 95% CI: 1.07, 1.09), or indigenous (OR: 1.11; 95% CI: 1.06, 1.15), were unmarried (OR: 1.08; 95% CI: 1.07, 1.08), illiterate (OR: 1.47; 95% CI: 1.42, 1.52), did not receive prenatal care (OR: 1.57; 95% CI: 1.53, 1.60), or were aged 14–20 y (OR: 1.21; 95% CI: 1.20, 1.22) or 35–49 y (OR: 1.12; 95% CI: 1.10, 1.13). Considering LGA children, higher odds were found in infants born to women living in households with ≥3 inadequate housing conditions (OR: 1.11; 95% CI: 1.10, 1.12), in indigenous women (OR: 1.22; 95% CI: 1.19, 1.25), those who had 1–3 y of schooling (OR: 1.18; 95% CI: 1.17, 1.19), 1–3 prenatal visits (OR: 1.16; CI 95%: 1.14, 1.17), or were older (OR: 1.26; 95% CI: 1.25, 1.27). Conclusions: In poorer Brazilian populations, socioeconomic, racial, and maternal characteristics are consistently associated with the occurrence of SGA births, but remain less clearly linked to the occurrence of LGA births
High anti-SARS-CoV-2 antibody seroconversion rates before the second wave in Manaus, Brazil, and the protective effect of social behaviour measures: results from the prospective DETECTCoV-19 cohort
No full textAntecedentes: A cidade de Manaus, Brasil, viu dois colapsos do sistema de saúde devido à pandemia de COVID-19. Relatamos as taxas de soroconversão de anticorpos IgG do nucleocapsídeo anti-SARS-CoV-2 e fatores de risco associados em Manaus residentes antes da segunda onda da epidemia no Brasil. Métodos: Uma amostra de conveniência de adultos (idade ≥18 anos) residentes de Manaus foi publicidade do site da universidade na coorte do estudo DETECTCoV-19. A análise atual de soroconversão incluiu um subgrupo de participantes do DETECTCoV-19 que teve pelo menos duas coletas de amostras de soro separadas por pelo menos 4 semanas entre 19 de agosto e 2 de outubro de 2020 (visita 1) e 19 de outubro e 27 de novembro de 2020 (visita 2). Aqueles que relataram (ou tiveram sem dados sobre) ter um diagnóstico de COVID-19 antes da visita 1 e que foram positivos para IgG de nucleocapsídeo anti-SARS-CoV-2 anticorpos na visita 1 foram excluídos. Usando um ELISA interno, o índice de reatividade (RI; calculado como a densidade óptica proporção da amostra para o controle negativo) para anticorpos IgG anti-nucleocapsídeo anti-SARS-CoV-2 sérico foi medido em ambas as visitas. Calculamos a incidência de soroconversão (definida como valores de RI ≤1·5 na visita 1 e ≥1·5 na visita 2, e uma razão >2 entre os valores de IR da visita 2 e da visita 1) durante o período do estudo, bem como taxas de incidência (IRRs) por meio de modelos de regressão de Poisson corrigidos por cluster e ajustados para analisar associações entre soroconversão e variáveis relacionadas a características sociodemográficas, acesso à saúde, comorbidades, exposição à COVID-19, comportamentos protetores e sintomas. Resultados: 2.496 participantes da coorte DETECTCoV-19 retornaram para uma visita de acompanhamento entre 19 de outubro e 27 de novembro de 2020, de dos quais 204 relataram ter COVID-19 antes da primeira visita e 24 não tinham dados sobre o status anterior da doença. 559 participantes foram soropositivos para anticorpos anti-SARS-CoV-2 nucleocapsid IgG na linha de base. Do restante 1.709 participantes que eram soronegativos no início do estudo, 71 não preencheram os critérios para soroconversão e foram excluídos a partir das análises. Entre os 1.638 participantes restantes que eram soronegativos no início do estudo, 214 mostraram soroconversão na visita 2. A incidência de soroconversão foi de 13,06% (IC 95% 11,52–14,79) em geral e 6,78% (5·61–8·10) para soroconversão sintomática, durante um período médio de acompanhamento de 57 dias (IQR 54–61). 48,1% de eventos de soroconversão foram estimados como assintomáticos. A amostra apresentou maiores proporções de pessoas abastadas e com nível superior do que aquelas relatadas para a população da cidade de Manaus. No modelo totalmente ajustado e corrigido, o risco fatores de soroconversão antes da visita 2 foram ter um caso de COVID-19 no domicílio (IRR 1·49 [IC 95% 1·21–1·83]), não usar máscara durante o contato com uma pessoa com COVID-19 (1·25 [1·09–1·45]), relaxamento do distanciamento físico (1·31 [1·05–1·64]) e com sintomas de gripe (1·79 [1·23–2·59]) ou um diagnóstico de COVID-19 (3·57 [2·27– 5·63]) entre a primeira e a segunda visita, enquanto o trabalho remoto foi associado à menor incidência (0,74 [0,56–0,97]). Interpretação: Um intenso período de transmissão de infecção precedeu a segunda onda de COVID-19 em Manaus. Diversos comportamentos modificáveis aumentaram o risco de soroconversão, incluindo o não cumprimento de medidas de intervenção como não uso de máscara durante o contato, relaxamento das medidas de proteção e trabalho não remoto. É necessário aumentar os testes em áreas de alta transmissão para fornecer informações oportunas sobre transmissão e ajudar na implementação apropriada de medidas de mitigação da transmissão.Ministério da Educação, Brasil; Fundação de Amparo à Pesquisa do Estado do Amazonas; Pan-Americano
Organização da Saúde (OPAS)/OMS.Background: The city of Manaus, Brazil, has seen two collapses of the health system due to the COVID-19 pandemic. We report anti-SARS-CoV-2 nucleocapsid IgG antibody seroconversion rates and associated risk factors in Manaus residents before the second wave of the epidemic in Brazil. Methods: A convenience sample of adult (aged ≥18 years) residents of Manaus was recruited through online and university website advertising into the DETECTCoV-19 study cohort. The current analysis of seroconversion included a subgroup of DETECTCoV-19 participants who had at least two serum sample collections separated by at least 4 weeks between Aug 19 and Oct 2, 2020 (visit 1), and Oct 19 and Nov 27, 2020 (visit 2). Those who reported (or had no data on) having a COVID-19 diagnosis before visit 1, and who were positive for anti-SARS-CoV-2 nucleocapsid IgG antibodies at visit 1 were excluded. Using an in-house ELISA, the reactivity index (RI; calculated as the optical density ratio of the sample to the negative control) for serum anti-SARS-CoV-2 nucleocapsid IgG antibodies was measured at both visits. We calculated the incidence of seroconversion (defined as RI values ≤1·5 at visit 1 and ≥1·5 at visit 2, and a ratio >2 between the visit 2 and visit 1 RI values) during the study period, as well as incidence rate ratios (IRRs) through cluster-corrected and adjusted Poisson regression models to analyse associations between seroconversion and variables related to sociodemographic characteristics, health access, comorbidities, COVID-19 exposure, protective behaviours, and symptoms. Findings: 2496 DETECTCoV-19 cohort participants returned for a follow-up visit between Oct 19 and Nov 27, 2020, of whom 204 reported having COVID-19 before the first visit and 24 had no data regarding previous disease status. 559 participants were seropositive for anti-SARS-CoV-2 nucleocapsid IgG antibodies at baseline. Of the remaining 1709 participants who were seronegative at baseline, 71 did not meet the criteria for seroconversion and were excluded from the analyses. Among the remaining 1638 participants who were seronegative at baseline, 214 showed seroconversion at visit 2. The seroconversion incidence was 13·06% (95% CI 11·52–14·79) overall and 6·78% (5·61–8·10) for symptomatic seroconversion, over a median follow-up period of 57 days (IQR 54–61). 48·1% of seroconversion events were estimated to be asymptomatic. The sample had higher proportions of affluent and highereducated people than those reported for the Manaus city population. In the fully adjusted and corrected model, risk factors for seroconversion before visit 2 were having a COVID-19 case in the household (IRR 1·49 [95% CI 1·21–1·83]), not wearing a mask during contact with a person with COVID-19 (1·25 [1·09–1·45]), relaxation of physical distancing (1·31 [1·05–1·64]), and having flu-like symptoms (1·79 [1·23–2·59]) or a COVID-19 diagnosis (3·57 [2·27–5·63]) between the first and second visits, whereas working remotely was associated with lower incidence (0·74 [0·56–0·97]). Interpretation: An intense infection transmission period preceded the second wave of COVID-19 in Manaus. Several modifiable behaviours increased the risk of seroconversion, including non-compliance with non-pharmaceutical interventions measures such as not wearing a mask during contact, relaxation of protective measures, and nonremote working. Increased testing in high-transmission areas is needed to provide timely information about ongoing transmission and aid appropriate implementation of transmission mitigation measures
The ongoing evolution of variants of concern and interest of SARS-CoV-2 in Brazil revealed by convergent indels in the amino (N)-terminal domain of the Spike protein (preprint)
No full textA Rede Genômica Fiocruz é formada por especialistas de todas as unidades da Fundação no país e de institutos parceiros que se empenham diariamente em gerar dados mais robustos sobre o comportamento do SARS-Cov-2 e contribuir para um melhor preparo do país no enfrentamento da pandemia em termos de diagnóstico mais precisos e vacinas eficazes. Saiba mais sobre a Rede Genômica Fiocruz em: http://www.genomahcov.fiocruz.br/Fiocruz
COVID-19 Genomic Surveillance Network (http://www.genomahcov.fiocruz.br/)
members, the Respiratory Viruses Genomic Surveillance Network of the General
Laboratory Coordination (CGLab), Brazilian Ministry of Health (MoH), Brazilian
Central Laboratory States (LACENs) and the Amazonas surveillance teams for the
partnership in the viral surveillance in Brazil. Financial support was provided by
FAPEAM (PCTI-EmergeSaude/AM call 005/2020 and Rede Genômica de Vigilancia
em Saúde - REGESAM); Ministério da Ciência, Tecnologia, Inovações e
Comunicações/Conselho Nacional de Desenvolvimento Científico e Tecnológico -
CNPq/Ministério da Saúde - MS/FNDCT/SCTIE/Decit (grants 402457/2020-9 and
403276/2020-9); Inova Fiocruz/Fundação Oswaldo Cruz (Grants
VPPCB-007-FIO-18-2-30 and VPPCB-005-FIO-20-2-87) and INCT-FCx
(465259/2014-6). Computer allocation was partly granted by the Brazilian National
Scientific Computing Center (LNCC). FGN, GLW, RDL and GB are supported by the
CNPq through their productivity research fellowships (306146/2017-7, 303902/2019-1,
425997/2018-9 and 302317/2017-1 respectively). G.B. is also funded by the Fundação
Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro – FAPERJ
(Grant number E-26/202.896/2018).Mutations at both the receptor-binding domain (RBD) and the amino (N)-terminal domain (NTD) of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Spike (S) glycoprotein can alter its antigenicity and promote immune escape. We identified that SARS-CoV-2 lineages circulating in Brazil with mutations of concern in the RBD independently acquired convergent deletions and insertions in the NTD of the S protein, which altered the NTD antigenic-supersite and other predicted epitopes at this region. Importantly, we detected the community transmission of different P.1 lineages bearing NTD indels Δ69-70 (which can impact several SARS-CoV-2 diagnostic protocols), Δ144 and ins214ANRN, and a new VOI N.10 derived from the B.1.1.33 lineage carrying three NTD deletions (Δ141– 144, Δ211, and Δ256–258). These findings support that the ongoing widespread transmission of SARS-CoV-2 in Brazil generates new viral lineages that might be more resistant to antibody neutralization than parental variants of concern
Natural disasters, population displacement and health emergencies: multiple public health threats in Mozambique
No full textNational Institute of Health of
Mozambique. VAM and GSR received scholarships from the Brazilian National
Council for Scientific and Technological Development (CNPq).In early 2019, following the 2015–2016 severe drought,
the provinces of Sofala and Cabo Delgado, Mozambique,
were hit by Cyclones Idai and Kenneth, respectively. These
were the deadliest and most destructive cyclones in the
country’s history. Currently, these two provinces host tens
of thousands of vulnerable households due to the climatic
catastrophes and the massive influx of displaced people
associated with violent terrorist attacks plaguing Cabo
Delgado. The emergence of the COVID-19 pandemic added
a new challenge to this already critical scenario, serving as
a real test for Mozambique’s public health preparedness.
On the planetary level, Mozambique can be viewed as a
‘canary in the coal mine’, harbingering to the world the
synergistic effects of co-occurring
anthropogenic and
natural disasters. Herein, we discuss how the COVID-19
pandemic has accentuated the need for an effective and
comprehensive public health response in a country already
deeply impacted by health problems associated with
natural disasters and population displacemen
Identificação de elementos rhabdovirais endógenos (EREs) em células embrionárias, adultos de Lutzomyia longipalpis e outros flebotomíneos
No full textInsetos vetores são responsáveis pela transmissão de diferentes patógenos. Dentre os principais insetos vetores destacam-se os flebotomíneos. Os flebotomíneos dos gêneros Phlebotomus e Lutzomyia são os principais vetores das leishmanioses que ocorrem no Velho e Novo Mundo, respectivamente. Além de serem vetores das leishmanioses, os flebotomíneos do Velho Mundo, são reconhecidamente vetores de várias arboviroses. Pouco se sabe sobre a capacidade vetorial de flebotomíneos do Novo Mundo em transmitir viroses para humanos, mas a ocorrência de populações de Lutzomyia spp. naturalmente infectadas por diferentes vírus tem sido demonstrada. Nosso grupo tem desenvolvido estudos com Lutzomyia longipalpis, o principal vetor da leishmaniose visceral no Brasil. Um dos principais modelos utilizados para estudos in vitro sobre L. longipalpis são as células embrionárias LL-5. Essas células, quando transfectadas com RNAs de dupla fita, independente das sequências desses RNAs passam a apresentar uma atividade antiviral inespecífica e o meio condicionado dessas células também é capaz de induzir esse fenótipo antiviral em células não transfectadas. A análise microscópica do meio condicionado identificou a presença de exossomos e além dessas vesículas, também foi observada a presença de possíveis partículas virais. Deste material foram identificados RNAs que codificavam para quatro diferentes proteínas de Rhabdovírus, sendo três delas de Nucleocapsídeo e uma RNA Polimerase dependente de RNA Através de reações em cadeia da polimerase, essas sequências foram identificadas em amostras de cDNA de células LL-5, e potencialmente em amostras de insetos adultos. Nas amostras de DNA, também foi possível identificar a presença dessas sequências, indicando uma possível inserção no genoma. A presença desses elementos rhabdovirais endógenos (EREs) foi confirmada por estudos in silico e in vitro. Além disso, neste projeto investigamos a presença dessas inserções em diferentes populações de flebotomíneos do Novo Mundo. A grande maioria das amostras testadas apresentou inserção no genoma e muitas delas apresentaram também transcritos referentes às inserções. Dentre elas L. longipalpis, L. umbratilis, Lutzomyia davisi, Lutzomyia whitmani e Lutzomyia fischeri, sendo todos esses insetos de diferentes regiões do Brasil. Porém, nenhuma das amostras do Velho Mundo testada, apresentou estas inserções no genoma, sendo estas: Phlebotomus arabicus, Phlebotomus argentipes, Phlebotomus papatasi, Phlebotomus sergenti e Sergentomyia schwetziInsect vectors are responsible for the transmission of different pathogens. Among the main insect vectors, phlebotomine sandflies stand out. Among these the genera Phlebotomus and Lutzomyia are the main vectors of leishmaniasis in the Old and New World, respectively. In addition to being vectors of leishmaniasis, the Old World phlebotomines are known to be vectors of several arboviruses. Little is known about the vectorial capacity of New World sandflies in the transmission of viruses to humans, although the occurrence of Lutzomyia spp. naturally infected by different viruses has been demonstrated. Our group has carried out various studies with Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Brazil. One of the main models used for L. longipalpis in vitro studies is the LL-5 embryonic cell line. These cells, when transfected with double-stranded RNAs, showed non-specific antiviral activity and the conditioned medium of these cells induces this antiviral phenotype in non-transfected cells. The analysis of the exosomal pellet by electron microscopy identified possible viral particles. In this material, RNAs that encoded four different Rhabdovirus proteins were identified. Three of them codified Nucleocapsids and one of them an RNAdependent RNA Polymerase. Through polymerase chain reactions, these sequences were identified in cDNA samples from LL-5 cells, and later in samples from adult insects These sequences were also iden-tified in DNA samples, indicating a possible insertion into the genome. The presence of these endogenous rhabdoviral elements (EREs) were confirmed by in silico and in vitro studies. In this project, we also investigated the presence of these inserts in different populations of sandflies in the New World. The majority of the tested samples had insertions into the genome and many of them also had transcripts, among them L. longipalpis, L. umbratilis, Lutzomyia davisi, Lutzomyia whitmani and Lutzomyia fischeri, all of which are from different regions of Brazil. However, none of the tested Old World samples showed any insertions into the genome: Phlebotomus arabicus, Phlebotomus argentipes, Phlebotomus papatasi, Phlebotomus sergenti and Sergentomyia schwetz
The Human Rights to Water and Sanitation in Policy Responses to the COVID-19 Pandemic: An Analysis of Brazilian States
No full textThe outbreak of the new coronavirus disease (COVID-19) led to an unprecedented number of policy responses from public institutions involved in the health and economic sectors. Nonetheless, the water, sanitation, and hygiene (WASH) sector remained in the background of this decision-making arena. The objective of the study presented herein was to observe and discuss political responses to the new coronavirus pandemic in the context of WASH during the first 40 days of the outbreak, using as cases the five Brazilian states most affected by the pandemic. We addressed this issue with a quali-quantitative exploratory study using content analysis to discuss the direction (for whom and how?) of those policy responses, through the framework of the human rights to water and sanitation. The paper also introduces a timeline to map the reactivity and proactivity of the studied institutions. We identified two major priorities in policy responses to the coronavirus pandemic: population protection and financial and economic sustainability of service providers. In regard to population protection, the findings show that it often did not contemplate all of the population, and that equality and non-discriminations were partially ignored in the laws and regulations. In addition, institutions more attached to service providers were more committed to the provider’s economic and financial sustainability than to measures to directly protect the population
Asymptomatic Leishmania infection in HIV-positive outpatients on antiretroviral therapy in Pernambuco, Brazil
No full textBackground: Visceral leishmaniasis (VL) in HIV-positive individuals is a global health problem. HIV-Leishmania coinfection worsens prognosis and mortality risk, and HIV-Leishmania coinfected individuals are more susceptible to VL relapses. Early initiation of antiretroviral therapy can protect against Leishmania infection in individuals living in VL-endemic areas, and regular use of antiretrovirals might prevent VL relapses in these individuals. We conducted a cross-sectional study in Petrolina, Brazil, an VL-endemic area, to estimate the prevalence of asymptomatic Leishmania cases among HIV-positive outpatients.
Methods: We invited any HIV-positive patients, aged ≥ 18-years-old, under antiretroviral therapy, and who were asymptomatic for VL. Patients were tested for Leishmania with enzyme-linked immunosorbent assays (ELISA)-rK39, immunochromatographic test (ICT)-rK39, direct agglutination test (DAT), latex agglutination test (KAtex), and conventional polymerase chain reaction (PCR). HIV-Leishmania coinfection was diagnosed when at least one VL test was positive.
Results: A total of 483 patients were included. The sample was predominantly composed of single, < 48-years-old, black/pardo, heterosexual males, with fewer than 8 years of schooling. The prevalence of asymptomatic HIV-Leishmania coinfection was 9.11% (44/483). HIV mono-infected and HIV-Leishmania coinfected groups differed statistically significantly in terms of race (p = 0.045), marital status (p = 0.030), and HIV viral load (p = 0.046). Black/pardo patients, married patients, and those with an HIV viral load up to 100,000 copies/ml presented higher odds for HIV-Leishmania coinfection.
Conclusions: A considerable number of asymptomatic Leishmania cases were observed among HIV-positive individuals in a VL-endemic area. Given the potential impact on transmission and health costs, as well as the impact on these coinfected individuals, studies of asymptomatic Leishmania carriers can be useful for guiding public health policies in VL-endemic areas aiming to control and eliminate the disease
Chagas heart disease: An overview of diagnosis, manifestations, treatment, and care
No full textChagas heart disease (CHD) affects approximately 30% of patients chronically infected with the protozoa Trypanosoma cruzi. CHD is classified into four stages of increasing severity according to electrocardiographic, echocardiographic, and clinical criteria. CHD presents with a myriad of clinical manifestations, but its main complications are sudden cardiac death, heart failure, and stroke. Importantly, CHD has a higher incidence of sudden cardiac death and stroke than most other cardiopathies, and patients with CHD complicated by heart failure have a higher mortality than patients with heart failure caused by other etiologies. Among patients with CHD, approximately 90% of deaths can be attributed to complications of Chagas disease. Sudden cardiac death is the most common cause of death (55%-60%), followed by heart failure (25%-30%) and stroke (10%-15%). The high morbimortality and the unique characteristics of CHD demand an individualized approach according to the stage of the disease and associated complications the patient presents with. Therefore, the management of CHD is challenging, and in this review, we present the most updated available data to help clinicians and cardiologists in the care of these patients. We describe the clinical manifestations, diagnosis and classification criteria, risk stratification, and approach to the different clinical aspects of CHD using diagnostic tools and pharmacological and non-pharmacological treatments
Nota Técnica 17 de 8 de abril de 2021. Redes de Atenção à Saúde para Covid-19 e os desafios das esferas governamentais: macrorregiões de saúde e a curva que devemos “achatar”
No full textMonitoraCovid-19: https://bigdata-covid19.icict.fiocruz.br/Segundo dados do CNES apenas 741 municípios apresentam capacidade de atendimento de alta complexidade para Covid-19 (UTI). Dados do SIVEP-Gripe de abril de 2020 a fevereiro de 2021 apontam que pouco menos de um quinto dos (1.029) municípios no país conseguiram atender mais de
10% dos casos de residentes que demandaram atendimento em UTI. Considerando o total de internações por Covid-19 nem metade dos 5.570 municípios conseguiu atender mais de 10% (2.085) dos casos da doença em residentes. A análise dos fluxos de internação aponta que as redes de atendimentos para hospitalização de casos de Covid-19 se assemelham às Macrorregiões de Saúde
compostas por um conjunto de municípios que devem tomar medidas compartilhadas para aumento da restrição ou relaxamento das medidas de distanciamento social. Em áreas de fronteira entre alguns estados, a circulação de pessoas vai além dos limites territoriais das UFs, o que demanda decisão compartilhada entre estes Estados com apoio do governo Federal
Associations between cesarean delivery and child mortality: a national record linkage longitudinal study of 17.8 million births in Brazil
No full textInfectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom / Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil. Infectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom. Infectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom / Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil. Infectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom. Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil. Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil /Universidade Federal da Bahia. Escola de Nutrição. Salvador, BA, Brasil. Infectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom. Infectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom / Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil. Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil. Fundação Oswaldo Cruz. Escola Nacional de Saúde Pública Sergio Arouca. Rio de Janeiro, RJ, Brasil. Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil / Universidade Federal da Bahia. Instituto de Saúde Coletiva, Salvador, BA, Brasil. Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil / Universidade Federal da Bahia. Instituto de Saúde Coletiva, Salvador, BA, Brasil. Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil. Infectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom. Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Centro de Integração de Dados e Conhecimento para a Saúde. Salvador, BA, Brasil. Infectious Disease Department. Faculty of Epidemiology and Population Health. London School of Hygiene & Tropical Medicine. London, United Kingdom.Wellcome Trust.Background: There is an increasing use of cesarean delivery (CD) based on preference rather than on medical indication. However, the extent to which nonmedically indicated CD benefits or harms child survival remains unclear. Our hypothesis was that in groups with a low indication for CD, this procedure would be associated with higher child mortality and in groups with a clear medical indication CD would be associated with improved child survival chances. Methods and findings: We conducted a population-based cohort study in Brazil by linking routine data on live births between January 1, 2012 and December 31, 2018 and assessing mortality up to 5 years of age. Women with a live birth who contributed records during this period were classified into one of 10 Robson groups based on their pregnancy and delivery characteristics. We used propensity scores to match CD with vaginal deliveries (1:1) and prelabor CD with unscheduled CD (1:1) and estimated associations with child mortality using Cox regressions. A total of 17,838,115 live births were analyzed. After propensity score matching (PSM), we found that live births to women in groups with low expected frequencies of CD (Robson groups 1 to 4) had a higher death rate up to age 5 years if they were born via CD compared with vaginal deliveries (HR = 1.25, 95% CI: 1.22 to 1.28; p < 0.001). The relative rate was greatest in the neonatal period (HR = 1.39, 95% CI: 1.34 to 1.45; p < 0.001). There was no difference in mortality rate when comparing offspring born by a prelabor CD to those born by unscheduled CD. For the live births to women with a CD in a prior pregnancy (Robson group 5), the relative rates for child mortality were similar for those born by CD compared with vaginal deliveries (HR = 1.05, 95% CI: 1.00 to 1.10; p = 0.024). In contrast, for live births to women in groups with high expected rates of CD (Robson groups 6 to 10), the child mortality rate was lower for CD than for vaginal deliveries (HR = 0.90, 95% CI: 0.89 to 0.91; p < 0.001), particularly in the neonatal period (HR = 0.84, 95% CI: 0.83 to 0.85; p < 0.001). Our results should be interpreted with caution in clinical practice, since relevant clinical data on CD indication were not available. Conclusions:In this study, we observed that in Robson groups with low expected frequencies of CD, this procedure was associated with a 25% increase in child mortality. However, in groups with high expected frequencies of CD, the findings suggest that clinically indicated CD is associated with a reduction in child mortality