1. 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
- Author
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Elisson Denny da Costa Carvalho, Antônio Vinicius Soares de Souza, Vitor Batista de Souza, Jaila Dias Borges Lalwani, Jackeline Vieira Guimarães, Maria Fiamma Farias Freitas, Ingrid Silva Correia, Michelle Araújo Ruiz, Fernanda Serrão Pereira, Neila Soares Picanço, Ilia Gilmara Carvalho dos Santos, Evillyn Fernandes Da Costa, Caio Lúcio Andreola da Silva, Josineide de Oliveira Novo França, Marne Carvalho de Vasconcellos, Roger V. Araujo-Castillo, Aguyda Rayany Cavalcante Barbosa, Marizete Candido Moraes, Wellington Barbosa de Melo, Cristiano Fernandes da Costa, Giane Alves da Silva, Pedro Elias de Souza, Aldina Iacy Paulain Holanda, André Victor Rabelo Monteiro, Isabelle Bezerra Cordeiro, Ana Paula Souza de França, Ivanildo Vieira Pereira Filho, Dalila de Alcântara Martins, Maele Ferreira Jordão, Genilton de Oliveira Cardenes, Ana Lúcia Silva Gomes, Bárbara Batista Salgado, Regiane Carneiro Bezerra, Jessica Samile Batista Pinheiro, Cinthya Iamile Frithz Brandão de Oliveira, Andressa dos Passos Santos, Spartaco Astofi-Filho, Susy Cavalcante Harjani, Milena Maria Cardoso de Lemos, Júlio Nino de Souza Neto, Brenda Pereira Farias, Juliana Correa Romana, Christian A. Ganoza, Rayara Gonzaga Maia, Enedina Nogueira de Assunção, Jessica Vanina Ortiz, Romeu Santos de Souza, Danielle Severino Sena da Silva, Fernanda Guilhon Simplicio, Matheus da Silva Damasceno, Gabriele Pimentel Sinimbu, Thiago Barros do Nascimento de Morais, Bianca Pires dos Santos, Beatriz Pinheiro, Kerollen Runa Pinto, Eline Araújo de Oliveira, Bruno Nicolau Paulino, Wlademir Braga Salgado Sobrinho, Iago Sampaio Fernandes da Costa, Bernardino Cláudio de Albuquerque, Pritesh Lalwani, and Antônia de Sousa Teixeira
- Subjects
virus nucleocapsid ,sensitivity analysis ,Prospective Studies ,Young adult ,Prospective cohort study ,disease transmission ,education ,receiver operating characteristic ,education.field_of_study ,adult ,Incidence (epidemiology) ,government ,social distancing ,size exclusion chromatography ,General Medicine ,cohort analysis ,income ,risk factor ,Cohort ,symbols ,Female ,Public aspects of medicine ,RA1-1270 ,medicine.symptom ,Brazil ,nucleocapsid protein ,prospective study ,Population ,Asymptomatic ,Article ,social behavior ,coronavirus disease 2019 ,symbols.namesake ,socioeconomics ,male ,Escherichia coli ,medicine ,controlled study ,diagnostic test accuracy study ,human ,immunoglobulin G antibody ,Poisson regression ,oropharyngeal swab ,Seroconversion ,Epidemics ,SARS-CoV-2 antibody ,seroconversion ,business.industry ,questionnaire ,COVID-19 ,major clinical study ,enzyme linked immunosorbent assay ,sensitivity and specificity ,Immunoglobulin G ,incidence ,business ,Demography - Abstract
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 higher-educated 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 non-remote working. Increased testing in high-transmission areas is needed to provide timely information about ongoing transmission and aid appropriate implementation of transmission mitigation measures. Funding: Ministry of Education, Brazil; Fundação de Amparo à Pesquisa do Estado do Amazonas; Pan American Health Organization (PAHO)/WHO. World Health Organization Revisión por pares
- Published
- 2021