ABSTRACT
Introduction One of the major criticisms facing the research community during SARS-CoV2 pandemic was the lack of large-scale, longitudinal data on the efficacy of the SARS-CoV2 mRNA vaccines. Currently, even if COVID-19 antiviral treatments have been authorized by European Medicine Agency, prevention through approved specific vaccines is the best approach available in order to contain the ongoing pandemic. Objectives Here, we studied the antibody kinetic over a one-year period from vaccination with the Pfizer-BioNTech (Pfizer) vaccines and subsequent boosting with either the BioNTech or Moderna (Spikevax) vaccines in a large cohort of 8,071 healthcare workers (HCW). We also described the impact of SARS-CoV2 infection on antibody kinetic over the same period. Methods We assessed the anti SARS-CoV2 Spike IgG antibody kinetic by the high throughput dried blood spot (DBS) collection method and the GSP®/DELFIA® Anti-SARS-CoV2 IgG assay (PerkinElmer®). Results Our data support existing models showing that SARS-CoV2 vaccination elicits strong initial antibodies responses that decline with time but are transitorily increased by administering a vaccine booster. We also showed that using heterologous vaccine/booster combinations a stronger antibody response was elicited than utilizing a booster from the same vaccine manufacturer. Furthermore, by considering the impact of SARS-CoV2 infection occurrence in proximity to the scheduled booster administration, we confirmed that booster dose did not contribute significantly to elicit higher antibody responses. Conclusion DBS sampling in our large population of HCWs was fundamental to collect a large number of specimens and to clarify the effective mRNA vaccine-induced antibody kinetic and the role of both heterologous boosters and SARS-CoV2 infection in modulating antibody responses.
ABSTRACT
Introduction: One of the major criticisms facing the research community during SARS-CoV2 pandemic was the lack of large-scale, longitudinal data on the efficacy of the SARS-CoV2 mRNA vaccines. Currently, even if COVID-19 antiviral treatments have been authorized by European Medicine Agency, prevention through approved specific vaccines is the best approach available in order to contain the ongoing pandemic. Objectives: Here, we studied the antibody kinetic over a one-year period from vaccination with the Pfizer-BioNTech (Pfizer) vaccines and subsequent boosting with either the BioNTech or Moderna (Spikevax) vaccines in a large cohort of 8,071 healthcare workers (HCW). We also described the impact of SARS-CoV2 infection on antibody kinetic over the same period. Methods: We assessed the anti SARS-CoV2 Spike IgG antibody kinetic by the high throughput dried blood spot (DBS) collection method and the GSP®/DELFIA® Anti-SARS-CoV2 IgG assay (PerkinElmer®). Results: Our data support existing models showing that SARS-CoV2 vaccination elicits strong initial antibodies responses that decline with time but are transitorily increased by administering a vaccine booster. We also showed that using heterologous vaccine/booster combinations a stronger antibody response was elicited than utilizing a booster from the same vaccine manufacturer. Furthermore, by considering the impact of SARS-CoV2 infection occurrence in proximity to the scheduled booster administration, we confirmed that booster dose did not contribute significantly to elicit higher antibody responses. Conclusion: DBS sampling in our large population of HCWs was fundamental to collect a large number of specimens and to clarify the effective mRNA vaccine-induced antibody kinetic and the role of both heterologous boosters and SARS-CoV2 infection in modulating antibody responses.
ABSTRACT
At the end of March 2020, just over a month after the first ascertained case of CoViD-19 infection in Italy, the first reports of acute lesions of acro-ischemia appeared, especially in pre-adolescents and adolescents. These manifestations have been called in the course of these months in various ways, from "acro-ischemia acuta", "erythema pernio", "chilblains", up to characterize them more recently as "CoViD Toes". Clinical manifestations do not usually associate with other typical symptoms of Covid-19 and do not find a classical and defined serological antibody response (IgG and IgM). From a clinical point of view it is a localized and self-resolving problem of an interesting and relatively new pathogenetic model of disease in relation to a viral agent. Future studies must make us understand if there is in this specific condition a low viral load is not detectable by current methods and if this explains the inability to produce an adequate immune response for CoViD-19. It is important to determine whether the interferon immune response in some subjects can be the cause of both the low viremia and the endothelial damage so localized in the acral-site, as happens in other models of diseases (chilblain-lupus like). On the contrary, some authors believe that the acral lesions are attributable to chilblains caused by a series of favourable environmental conditions due to forced enclosure. We report the descriptive experience of 14 cases of acro-ischemia in children and adolescents observed in the territorial area of Ravenna and Rimini. The cases were subjected to the nasopharyngeal swab and to the search for antibodies with ELISA method for CoViD-19 both with negative results.