ABSTRACT
Medical history of COVID-19 was an exclusion criterion in the clinical trial that led to the vaccination regimen of two-doses for the BNT162b2 SARS-CoV-2 mRNA vaccine. Herein, we have analyzed a wide panel of immune responses triggered by this immunization in a cohort of naïve and COVID-19-recovered individuals. Plasma levels of S-specific immunoglobulins peaked after one vaccine shot in COVID-19-recovered individuals, while a second dose was needed in naïve subjects to achieve similar levels. However, naïve individuals did not reach as much neutralizing titers as COVID-19-recovered participants did after a complete vaccination regimen. At that point, after T cell stimulation with S-protein antigens from SARS-CoV-2, naïve individuals exhibited higher cytokine production levels, CD4+ T cells activation and proliferation than COVID-19-recovered individuals. Moreover, patent inverse correlations were observed between humoral and cellular immune variables, discriminating naïve from COVID-19-recovered subjects. Our data indicate that a previous history of COVID-19 determines the functional T and B cell-mediated responses to BNT162b2 vaccination and, consequently, individual’s history should be considered prior to the vaccination regime.Funding Information: CdF, JGP and JA are supported by Instituto de Salud Carlos III (ISCII). Research in ELC’s lab is supported by Fundación Familia Alonso, Santander Bank, Real Seguros, Fundación Mutua Madrileña, Fundación Uria, Fundación Caixa and Ayuntamiento de Madrid. Declaration of Interests: The authors declare that no conflict of interest exists.Ethics Approval Statement: Informed consent was obtained from all volunteers in accordance with the ethical standards and following the ethical guidelines of the 1975 Declaration of Helsinki. All healthy health personnel data were anonymized before study inclusion
Subject(s)
COVID-19ABSTRACT
COVID-19 pandemic caused by SARS-CoV-2 led the Spanish government to impose a national lockdown in an attempt to control the spread of the infection. Mobility restrictions but also the requirement of a medical prescription to gain access to serological testing for COVID-19 were included among the measures. Under this scenario, between April 15th to June 15th, 2020, we performed a seroprevalence observational study including 449 individuals that fulfill prescription requirements: manifesting COVID-19 compatible symptoms, being in contact with a COVID-19 confirmed case or belonging to essential occupations including healthcare workers, firefighters or public safety personnel such as police. Importantly, none of the participants was hospitalized. Altogether, we studied this specific, non-commonly addressed cohort for SARS-CoV-2 seroprevalence, uncovering intrinsic features of great demographic interest. The overall rate of IgG seropositivity was 33.69% (95% CI: 29.27 – 38.21). This seroprevalence was comparable between different occupations performed by the participants. However, contacts with confirmed cases associated positively with IgG+ results, with stronger correlation if being a household member. The number of symptoms also correlated positively with IgG+ prevalence. Ageusia/anosmia, pneumonia and cutaneous manifestations were the top-three symptoms that most strongly associated with IgG+ seroprevalence. However, while pneumonia and cutaneous manifestations were barely present in our cohort, fever, ageusia/anosmia and asthenia were the most frequently symptoms described within IgG+ subjects. Therefore, our data illustrate how specific cohorts display heterogeneous characteristics that should be taken into account when identifying population seroprevalence against SARS-CoV-2 and key defining symptoms for COVID-19.