ABSTRACT
OBJECTIVE: The risk of reinfection with SARS-CoV-2 has been rapidly increased with the circulation of concerns about variants. So, the aim of our study was to evaluate the factors that increase the risk of this reinfection in healthcare workers compared to those who have never been positive and those who have had only one positivity. METHODS: A case-control study was carried out at the Teaching Hospital Policlinico Umberto I in Rome, Sapienza University of Rome, in the period between 6 March 2020 and 3 June 2022. Cases are healthcare workers who have developed a reinfection with the SARS-CoV-2 virus, while controls were either healthcare workers who tested positive once or those who have never tested positive for SARS-CoV-2. RESULTS: 134 cases and 267 controls were recruited. Female gender is associated with a higher odds of developing reinfection (OR: 2.42; 95% CI: 1.38-4.25). Moreover, moderate or high alcohol consumption is associated with higher odds of reinfection (OR: 1.49; 95% CI: 1.19-1.87). Diabetes is also associated with higher odds of reinfection (OR: 3.45; 95% CI: 1.41-8.46). Finally, subjects with increased red blood cell counts have higher odds of reinfection (OR: 1.69; 95% CI: 1.21-2.25). CONCLUSION: From the prevention point of view, these findings indicate that particular attention should be paid to subjects with diabetes mellitus, women and alcoholic drinkers. These results could also suggest that contact tracing represents a fundamental approach model against the SARS-CoV-2 pandemic, together with the health information of participants.
ABSTRACT
BACKGROUND: The 2019 coronavirus (COVID-19) epidemic, required the development of different diagnostic tests. While reverse transcriptase real-time PCR (RT-PCR) remains the first-line test of choice in acute infection diagnosis, anti-N antibodies serological assays provide a valuable tool to differentiate natural SARS-CoV-2 immunological response from that induced by vaccination, thus the goal of our study was to evaluate three serological tests agreement for these antibodies detection. METHODS: Three anti-N different tests were examined in 74 sera from patients referred or not COVID infection: immunochromatographic rapid test (Panbio™ COVID-19 IgG/IgM Rapid Test Device Abbott, Germany), ELISA kit (NovaLisa® SARS-CoV-2 IgG and IgM NovaTech Immunodiagnostic GmbH, Germany) and ECLIA immunoassay (Elecsys® Anti-SARS-CoV-2 Roche Diagnostics, Manheim, Germany). RESULTS: Qualitative comparison of the three analytical methods revealed a moderate agreement between ECLIA immunoassay and immunochromatographic rapid test (Cohen kappa coefficient κ = 0.564). Correlation analysis indicated weak positive correlation between total Ig (IgT) detected by ECLIA immunoassay and IgG by ELISA test (p < 0.0001), the analysis of ECLIA IgT and IgM ELISA detected, showed no statistical correlation. CONCLUSION: Comparison between of three analytical systems available for anti-N SARS-CoV-2 IgG and IgM antibodies showed a general agreement when compared to detect total and G class immunoglobulins, while doubtful or discordant results have been highlighted for IgT and IgM class. Anyway, all the tests examined provide reliable results to assess the serological status of SARS-CoV-2 infected patients.
Subject(s)
COVID-19 , SARS-CoV-2 , SARS-CoV-2/immunology , Humans , Antibodies/immunologyABSTRACT
To date, no comprehensive marker to monitor the immune status of patients is available. Given that Torque teno virus (TTV), a known human virome component, has previously been identified as a marker of immunocompetence, it was retrospectively investigated whether TTV viral load may also represent a marker of ability to develop antibody in response to COVID-19-BNT162B2 vaccine in solid organ transplant recipients (SOT). Specifically, 273 samples from 146 kidney and 26 lung transplant recipients after successive doses of vaccine were analyzed. An inverse correlation was observed within the TTV copy number and anti-Spike IgG antibody titer with a progressive decrease in viremia the further away from the transplant date. Analyzing the data obtained after the second dose, a significant difference in TTV copy number between responsive and nonresponsive patients was observed, considering a 5 log10 TTV copies/mL threshold to discriminate between the two groups. Moreover, for 86 patients followed in their response to the second and third vaccination doses a 6 log10 TTV copies/mL threshold was used to predict responsivity to the booster dose. Although further investigation is necessary, possibly extending the analysis to other patient categories, this study suggests that TTV can be used as a good marker of vaccine response in transplant patients.