F2 and pertussis: In this study, the GMCs of anti-PT and anti-FHA antibodies significantly increased after primary immunization (at 3, 4, and 5 months of age) and booster immunization (at 18–24 months of age), and compared with children who completed the entire series of pertussis vaccination, children who did not complete the vaccination course had lower levels of anti-PT and anti-FHA antibodies (PT: 17.88 IU/mL vs. 11.19 IU/mL, FHA: 27.37 IU/mL vs. 16.76 IU/mL).