Trifonova, I.; Ngoc, K.; Gladnishka, T.; Ivanova, V.; Kunchev, M.; Mutafchiyski, V.; Christova, I. SARS-COV-2 SEROSURVEY AMONG BULGARIAN HEALTHCARE WORKERS BEFORE AND AFTER VACCINATION. Probl Infect Parasit Dis 2023, 50 (3), 24-28. https://doi.org/10.58395/2zpwv014.