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Background: Toxoplasma gondii is estimated to infect 33% of blood donors worldwide, and seroprevalence varies widely between countries. We aimed to evaluate, for the first time, the seroprevalence and risk factors associated with T. gondii in blood donors from Western Romania. Methods: Serologic testing to demonstrate the presence of T. gondii antibodies was conducted in 1347 healthy blood donors. Risk factors for T. gondii infection were assessed through an epidemiological questionnaire. Results: The overall prevalence of T. gondii antibodies was 45.9%, with a significant age-associated increase (p < 0.001) from 32.6% in age group 18–25 years to 67.6% in age group 56–63 years. T. gondii seroprevalence decreased with increasing level of education, from 64.3% in individuals who graduated from elementary/middle school to 40.4% in those who graduated from University (p < 0.001). The multiple logistic regression analysis revealed that age, level of education and having pets (cats and/or dogs) were significantly associated with T. gondii infection. Conclusions: This study brings new and valuable data regarding the seroepidemiology of T. gondii infection in Romania. Our findings indicate a high prevalence of T. gondii antibodies in blood donors and may serve as a starting point for further epidemiological studies that should lead to implementation of prevention programs for toxoplasmosis.

Background and Objectives: Comprehension regarding immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is limited, and the durability of immune responses after vaccination is currently unknown. Several studies have reported on the antibody response in fully vaccinated individuals with a limited follow-up of the participants, i.e., below 7 months. Materials and Methods: The antibody response to complete vaccination with the BNT162b2 mRNA COVID-19 vaccine was assessed monthly, for 7 months, in 92 healthcare workers, between February 26 and September 26, 2021. The SARS-CoV-2 anti-spike protein IgG (IgGS) antibody was detected using the SARS-CoV-2 IgG II Quant assay (Abbott, Diagnostics Division, Sligo, Ireland), a chemiluminescent microparticle immunoassay (CMIA) with a sensitivity of 98.1% and specificity of 99.6%. Participants were divided into two groups, one for individuals previously infected with SARS-CoV-2 and the other for individuals without previous infection. Results: The median IgGS titers decreased monthly both in previously infected individuals and in the uninfected group. Previously infected individuals had significantly higher median titers of IgGS compared with previously uninfected subjects at all seven time points after complete vaccination (p < 0.001). Conclusions: Seven months after vaccination, the median IgGS titer had decreased by more than 92% both in individuals previously infected with SARS-CoV-2 and in uninfected individuals. However, IgGS antibodies were still detected in all study participants and persisted throughout the 7 months after the second dose of the vaccine. Further studies should be conducted to monitor the antibody response to the BNT162b2 mRNA vaccine beyond 7 months, to assess the need for a new booster dose in order to extend the duration and amplitude of the specific immune response.