摘要Objective:To evaluate the effectiveness of DTwP-HB-Hib vaccination dosing intervals at eight weeks versus four weeks on the immunogenicity of the diphtheria component.Methods:This is a randomized,open-label,parallel,controlled trial on healthy two-month-old infants who had not received DTwP-HB-Hib vaccinations.The infants received three doses of the vaccine either at an eight-week or four-week interval.The anti-diphtheria toxoid IgG antibody levels before and after three doses of the vaccination were measured using ELISA.Results:Eighty infants were enrolled in this study,with 64 fulfilling the study requirements and randomized into two groups.All study participants exhibited uncertain protection against diphtheria antibodies(0.01-0.99 IU/mL)at the beginning of the study with an average of(0.023±0.009)IU/mL and(0.026±0.009)IU/mL in eight weeks and four weeks groups.Following three doses of the vaccination,the antibody level rose to an average of(1.320±0.234)IU/mL in the eight-week group and(1.307±0.186)IU/mL in the four-week group,with no statistically significant difference in the antibody levels observed(P=0.814).Conclusions:DTwP-HB-Hib vaccinations can be administered at an eight-week or four-week interval,as they do not significantly affect the level of anti-diphtheria IgG antibodies.