"cases among persons who were not fully vaccinated compared with those among fully vaccinated persons" Read yourself carefully but this research seem to label partially vaccinated as unvaccinated or bunching up partially vaccinated with unvaccinated. I do not see the stats of non-vaccinated with vaccinated (partially or fully = both). I might be wrong but this seem to be the case. You have to remember that now vaccinated means the one who received two vaccines + 14 days.