The comparison of pandemic H1N1 IgG levels between H1N1 influenza-vaccinated healthcare workers and unvaccinated healthcare workers

Background/aim: To compare pandemic H1N1 (pH1N1) IgG antibody levels between healthcare workers who were vaccinated with the pH1N1 influenza vaccine and the unvaccinated healthcare workers who were selected as the control group. Materials and methods: A total of 68 healthcare workers were included in this study. Of those, 53 were adults vaccinated with the H1N1 influenza vaccine and 15 were unvaccinated. Serum samples were parsed and stored at –40 °C until they were examined. Results: Of the total 53 vaccinated healthcare workers, 16 (30.1%) were positive for IgG antibodies (titer 11), 17 (32.0%) were negative for IgG antibodies (titer 9), and 20 (37.7%) were borderline (titer: 9–11). Of the 15 unvaccinated healthcare workers, 1 (6.6%) was positive for IgG antibodies, 11 (73.3%) were negative for IgG antibodies, and the remaining 3 (20.0%) had borderline values (P = 0.014, P 0.05). In both groups, there was no statistically significant difference between IgG-negative, IgG-positive, and borderline subjects in terms of age or sex. Conclusion: The IgG antibody level was higher in the vaccinated healthcare workers than among the unvaccinated healthcare workers.