Longitudinal SARS-CoV-2 seroprevalence in Portugal and antibody maintenance 12 months after infection.
Eur J Immunol
; 52(1): 149-160, 2022 01.
Article
em En
| MEDLINE
| ID: mdl-34695227
ABSTRACT
During the COVID-19 pandemic, Portugal has experienced three distinct SARS-CoV-2 infection waves. We previously documented the prevalence of SARS-CoV-2 immunity, measured by specific antibodies, in September 2020, 6 months after the initial moderate wave. Here, we show the seroprevalence changes 6 months later, up to the second week of March 2021, shortly following the third wave, which was one of the most severe in the world, and 2 months following the start of the vaccination campaign. A longitudinal epidemiological study was conducted, with a stratified quota sample of the Portuguese population. Serological testing was performed, including ELISA determination of antibody class and titers. The proportion of seropositives, which was 2.2% in September 2020, rose sharply to 17.3% (95% CI 15.8-18.8%) in March 2021. Importantly, circulating IgG and IgA antibody levels were very stable 6 months after the initial determination and up to a year after initial infection, indicating long-lasting infection immunity against SARS-CoV-2. Moreover, vaccinated people had higher IgG levels from 3 weeks post-vaccination when compared with previously infected people at the same time post-infection.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Imunoglobulina A
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Imunoglobulina G
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Teste Sorológico para COVID-19
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SARS-CoV-2
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COVID-19
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Anticorpos Antivirais
Tipo de estudo:
Clinical_trials
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Observational_studies
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Prevalence_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adolescent
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Adult
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Female
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Humans
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Male
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Middle aged
País como assunto:
Europa
Idioma:
En
Ano de publicação:
2022
Tipo de documento:
Article