Saltoğlu, NeşeDinç, Harika ÖyküBalkan, İlker İnançCan, GünayÖzbey, DoğukanBeytur, Ayşe NurKeskin, ElifBudak, BeyhanAydoğan, OkanMete, BilgülKaraali, RıdvanErgin, Sevgi2022-08-082022-08-082022Saltoğlu, N., Dinç, H. Ö., Balkan, İ. İ., Can, G., Özbey, D., Beytur, A. N. ... Ergin, S. (2022). Heterologous booster COVID-19 vaccination elicited potent immune responses in HCWs. Diagnostic Microbiology and Infectious Disease, 104(2). https://doi.org/10.1016/j.diagmicrobio.2022.1157580732-8893https://doi.org/10.1016/j.diagmicrobio.2022.115758https://hdl.handle.net/20.500.12511/9636The objective of our study was to evaluate the antibody responses of health care workers (HCWs) who were vaccinated with booster dose BNT162b2 6 months after 2 doses of the CoronoVac vaccine. The study included 318 HCWs vaccinated with inactive CoronaVac SARS-CoV-2 vaccine in 2 doses. Anti-spike/RBD IgG levels were measured immediately before and 1 month after the booster dose. In the sixth month after CoronaVac vaccination, the median of antibody levels of 1212.02 AU/ML, while it was 9283 AU/mL after BNT162b2 vaccination. IgG antibody titers of over 1050 AU/mL (which is equivalent to 1:80 dilution in the plaque reduction neutralization test) were detected in HCWs 15.09% and 97.8%, respectively. Our results showed that antibody titers increased 8-fold after the booster dose. We believe that the administration of the mRNA vaccine as a booster dose can provide more effective protection against COVID-19 infection, especially in individuals with risk factors.eninfo:eu-repo/semantics/openAccessAntibodyBNT162b2CoronaVacCOVID-19VaccineArticle104210.1016/j.diagmicrobio.2022.115758Q30008341015000012-s2.0-8513473476935878507Q2