SARS-CoV-2 Seroprevalence Following a Large-Scale Vaccination Campaign in Portugal: Results of the National Serological Survey, September - November 2021

Autor: Irina Kislaya, Paulo Gonçalves, Sara Ramalhete, Marta Barreto, Ana Rita Torres, Vânia Gaio, Verónica Gómez, Carla Manita, João Almeida Santos, Sofia Soeiro, Rita de Sousa, Aryse Melo, Camila Henriques, Raquel Guiomar, Ana Paula Rodrigues, on Behalf of ISNCOVID-19 Group
Jazyk: English<br />Portuguese
Rok vydání: 2022
Předmět:
Zdroj: Acta Médica Portuguesa (2022)
Druh dokumentu: article
ISSN: 0870-399X
1646-0758
DOI: 10.20344/amp.18528
Popis: Introduction: Following a COVID-19 mass vaccination campaign, it is important to evaluate the population level of SARS-CoV-2 antibodies. The aim of this study was to estimate the seroprevalence rate of SARS-CoV-2 specific antibodies acquired due to infection or vaccination in the Portuguese population. Material and Methods: The National Serological Survey (third wave – ISN3COVID-19) is a cross-sectional nationwide epidemiological study developed on a sample of 4545 Portuguese residents aged one year or older, between the 28th September 2021 and the 19th November 2021. The SARS-CoV-2 anti-nucleoprotein and anti-spike IgG antibody levels were determined in serum samples using Abbott Chemiluminescent Microparticle Immunoassays. Seroprevalence estimates were stratified by age group, sex, administrative region and self-reported chronic conditions. Medians and respective 95% confidence intervals were used to describe the distribution of SARS-CoV-2 specific antibodies in specific population subgroups. Results: The total seroprevalence rate of SARS-CoV-2 was 86.4% (95% CI: 85.2% to 87.6%). A higher seroprevalence rate was estimated for women (88.3%), 50 to 59 years-old (96.5%) and in those with two or more self-reported chronic conditions (90.8%). A higher IgG (anti-Spike) concentration was observed in individuals vaccinated with the booster dose (median = 1 2601.3 AU/mL; 95% CI: 4127.5 to 19 089.1). Conclusion: There was a significant increase in SARS-CoV-2 seroprevalence following the mass vaccination campaign in Portugal. It is important to continue to monitor the distribution of specific SARS-COV-2 antibody at the population level to further inform public health policies.
Databáze: Directory of Open Access Journals
Externí odkaz: