https://www.selleckchem.com/products/og-l002.html In the context of the ongoing COVID-19 pandemic, using a half-dose schedule vaccination can help to return to normalcy in a cost-efficient manner, which is especially important for low and middle-income countries. We undertook a study to confirm that in adults up to 55 years old, the humoral response to the half-dose (15 µg, 35 participants between 18 and 55 years old) and to the recommended dose (30 µg, 155 participants) in the two-dose three-week interval schedule would be comparable. Antibody levels were measured by the Elecsys Anti-SARS-CoV-2 S assay (Roche Diagnostics, upper detection limit 2570 BAU/mL) on the day of dose 2 of the vaccine and then 8-10 days later to assess peak response to dose 2. The difference in proportions between the participants who did and did not exceed the upper detection limit 8-10 days after dose 2 was not statistically significant (p = 0.152). We suggest that a half-dose schedule can help to achieve widespread vaccination coverage more quickly and cheaply.The objectives of the cross-sectional study were to measure how behaviors and attitudes about preventive measures toward COVID-19 changed over time among Italian vaccinated healthcare workers and university students, and the associated characteristics. The study was carried out between February and March 2021 in the city of Naples, Campania region, Southern Italy. The perceived personal risk of being infected by SARS-CoV-2 after the vaccination was significantly higher among males, in those having a higher perceived personal risk of being infected by SARS-CoV-2 before the vaccination, and in those who were more concerned about the efficacy of the vaccination. The fear of getting the disease as reason to have the COVID-19 vaccination was reported more frequently in younger participants, in those with at least one chronic medical condition, in those with a higher concern about the severity of COVID-19, in those with a higher level of