Views and Attitudes of Blood Donors toward Blood Donation during the COVID-19 Pandemic in Thrace Region, Greece.

The COVID-19 pandemic has been going on for the last two years and it has affected our society and, amongst other things, has had a negative impact on blood donation, which has led to a significant reduction in blood supplies worldwide. The imposed restrictions in terms of physical presence and transportation, and the fear of the unknown, have aggravated the situation. In Greece, after the first cases of COVID-19 were reported, the blood supplies at the blood transfusion units (BTUs) were dramatically reduced. Although the blood transfusions were lessened during the COVID-19 pandemic period, the blood stocks at all the BTUs of the country were also reduced.

Prevalence of anti-SARS-CoV-2 IgG antibodies in a group of patients, a control group, and healthcare workers of Thrace area in Greece, by the use of two distinct methods.

INTRODUCTION: The aim of this study was to assess the clinical performance of different automated immunoassays available in Europe to detect anti-SARS-CoV-2 antibodies; an ELISA assay and a CLIA. The second goal was to estimate the seroprevalence of SARS-CoV-2 antibodies among healthcare workers in Evros area during the first pandemic wave of COVID-19. METHODS: The study included serum samples from 101 patients with confirmed COVID-19 by RT-PCR and 208 negative patients. Furthermore, it included 1036 healthcare workers (HWs) of the Evros Region, Northern Greece. The measurement of anti-SARS-CoV-2 antibodies was performed using the Abbott SARS-CoV-2 IgG and anti-SARS-CoV-2 ELISA IgG assay (Epitope Diagnostics, USA). RESULTS: Of 101 confirmed COVID-19 patients, 82 were hospitalized and 19 were outpatients. Hospitalized patients had higher IgG levels in comparison to outpatients (6.46±2.2 vs. 3.52±1.52, p<0.001). Of 208 non-COVID-19 patients only 1 was positive in both ELISA and CLIA assay. SARS-CoV-2-IgG antibodies were detected in 6 HWs out of 1036 (0.58%) with mean S/CO-value of anti-SARS-CoV-2 IgG 3.12±1.3 (confidence interval 0.95), which was lower than in COVID-19 patients (3.12 vs. 5.9; p=0.016). The clinical evaluation of two immunoassays showed remarkably high true positivity rates in the confirmed COVID-19 patients. Sensitivities obtained with CLIA and ELISA methods were 99.02% vs. 97.09% and specificities 99.52% vs 99.05% respectively. CONCLUSIONS: We found an acceptable accordance between CLIA and ELISA assays in the confirmed COVID-19 patients. In all subjects included in this study in the past medical history, the information that was obtained included details about the presence of autoimmune diseases.

Levels of Produced Antibodies after Vaccination with mRNA Vaccine; Effect of Previous Infection with SARS-CoV-2.

The aim of this study was to estimate the immunogenic effect of mRNA vaccine against SARS-CoV-2. This study included 510 participants who received mRNA vaccine. The measurement of anti-COVID-19 antibodies was performed using the Abbott SARS-CoV-2 IgG quantitative assay (Abbott). Overall, mean titer of anti-Spike antibodies was 19,319.2 ± 1787.5 AU/mL. Vaccination induced a robust immunogenic response in those previously infected with SARS-CoV-2 compared with non-infected subjects. Additionally, individuals that were asymptomatic after vaccination produced lower levels of antibodies compared to feverish individuals. In conclusion, remarkably high levels of anti-Spike COVID-19 antibodies were observed after vaccination.

The prevalence of HCV RNA positivity in anti-HCV antibodies-negative hemodialysis patients in Thrace Region. Multicentral study.

INTRODUCTION: HCV infection in patients under hemodialysis for end stage chronic kidney disease (ESCKD) may exist despite the absence of anti-HCV antibodies. Molecular methods are widely accepted as "gold standard" techniques for the detection of viral RNA. However, the molecular methods are more expensive in comparison to conventional methods and their replacement is not cost-effective. The aim of this study was to estimate the prevalence of HCV RNA positivity in anti-HCV negative hemodialysis patients and evaluate new diagnostic methods for the detection and the monitoring of hepatitis C in ESCKD patients. METHODS: The study was performed in four hospitals of Thrace region of Greece and 233 patients with no history of hepatitis C were enrolled. Measurement of anti-HCV antibodies and HCV core antigen was performed by microparticle chemiluminescence immunoassay. Molecular detection of viral RNA was performed by the real-time RT PCR. RESULTS: The mean age of the patients was 64.9 ± 23.3 years. HCV-Ag was positive in 2/233 patients (0.86%). Nevertheless, viral RNA was negative in those patients. CONCLUSIONS: The results of the present study showed that the incidence of HCV-RNA in patients with negative anti-HCV Abs, in hemodialysis patients in Thrace region of Greece was negligible (0/233).