Vaccination time does not influence total anti-SARS-CoV-2 antibodies response

We measured total anti-SARS-CoV-2 receptor-biding domain (RBD) antibodies in 249 healthcare workers (mean age: 44 ± 13 years; 151 women), who received the first dose of mRNA-based Comirnaty COVID-19 vaccine at different times of the day. Compared with the reference vaccination time point (i.e. <10:00h), vaccine injection at the following times of day elicited a comparable response (all p > 0.05). Under our experimental conditions, we can therefore exclude a possible influence of the timing of primary mRNA-based COVID-19 vaccination on the levels of total anti-SARS-CoV-2 antibodies.