Assessment of Anti-SARS-CoV-2 Antibodies Post-Coronavac Vaccination in the Amazon Region of Brazil

Autor: Carlos David Araújo Bichara, Maria Alice Freitas Queiroz, Ednelza da Silva Graça Amoras, Gergiane Lopes Vaz, Izaura Maria Vieira Cayres Vallinoto, Cléa Nazaré Carneiro Bichara, Isabella Pinheiro Costa do Amaral, Ricardo Ishak, Antonio Carlos Rosário Vallinoto
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Vaccines, Vol 9, Iss 10, p 1169 (2021)
Druh dokumentu: article
ISSN: 2076-393X
DOI: 10.3390/vaccines9101169
Popis: The present study evaluated the frequency of seropositivity for anti-SARS-CoV-2 (S1 and S2) total antibodies and anti-SARS-CoV-2 (receptor binding domain-RBD-S1) neutralizing antibodies in individuals vaccinated with the immunizing agent Coronavac. This was a cross-sectional study involving 358 individuals divided into two groups. Group 1 consisted of 205 volunteers who were tested for anti-SARS-CoV-2 total antibodies; group 2 consisted of 153 individuals tested for the presence of anti-SARS-CoV-2 neutralizing antibodies. Seropositivity was greater than 70% in both groups, although 17.6% and 20.9% of individuals showed no neutralizing or total antibody reactivity, respectively. The frequency of anti-SARS-CoV-2 total antibodies displayed a significantly different distribution between the sexes but not according to age. The frequency of anti-SARS-CoV-2 neutralizing antibodies was 93.3% (95% CI 68.1–99.8) in the age group from 21 to 40 years but significantly decreased with advancing age, and was 76.2% (95% CI 52.8–91.8) for 41 to 60 years, 72.5% (95% CI 62.8–80.9) for 61 to 80 years, and 46.7% (95% CI 21.3–73.4) for >80 years. Our results reveal a high prevalence of anti-SARS-CoV-2 total antibodies and anti-SARS-CoV-2 neutralizing antibodies in individuals who received both doses of the Coronavac vaccine, suggesting a lower effectiveness of the humoral immune response among those older than 60 years of age, which might be associated with senescence of the immune system.
Databáze: Directory of Open Access Journals