Table 1.

Groups of volunteers according to their vaccination status (no, one, two or three vaccine doses) and/or convalescent status (no, one or two reported positive SARS-CoV-2 PCR or AG tests as a documentation of infection/reinfection). Number of volunteers/number of serological data throughout the study visits are reported. Of importance, volunteers could be included and drop out at any of the four study visits.

Immune status	One reported positive test	Two reported positive tests	No reported positive RT-PCR or AG tests	Total
Convalescent	89/139	6/15	96/118
Vaccination 1 dose	30/75	10/22	57/75
Vaccination 2 doses	68/172	17/48	183/296
Vaccination 3 doses	82/227	6/19	129/255
Total	269	39	465	773/1461