Objective: To compare the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine used for the vaccination in public security officers with different immunization schedules. Methods: From January to February, 2021, 405 public security officers in Taiyuan were randomly divided into 3 groups. Two doses of SARS-CoV-2 inactivated vaccine were injected according to the immunization schedule of 0-14 days, 0-21 days or 0-28 days, respectively. The nucleic acid of SARS-CoV-2 was detected by reverse transcription polymerase chain reaction. The neutralizing antibodies to SARS-CoV-2 were tested by microdose cytopathogenic efficiency assay of live virus. The GMT, seroconversion rate of SARS-CoV-2 neutralizing antibody and safety of the vaccine were analyzed for the 3 groups. Results: The seroconversion rate of SARS-CoV-2 neutralizing antibody was 100% in all the 3 groups. The SARS-CoV-2 neutralizing antibody level of 0-21 day group [166.70 (95%CI: 148.30-185.10)] was similar to that of 0-28 day group [179.50 (95%CI: 156.50-202.60)] (P>0.05), significantly higher than that of 0-14 day group [86.08 (95%CI: 72.36-99.80)] (P<0.001). The incidence rates of adverse reaction in the 3 groups were 1.48% (2/135), 0.74% (1/136) and 1.49% (2/134) respectively (P=0.750), all the adverse reactions were mild. Conclusions: The vaccination of inactivated SARS-CoV-2 vaccine with different immunization schedules in public security officers showed good safety and high seroconversion rate, and the GMTs of SARS-CoV-2 neutralizing antibody in 0-21 day group and 0-28 day group were higher than that in 0-14 day group.
目的： 比较公安人员按不同方案（0~14 d、0~21 d、0~28 d）接种新型冠状病毒（新冠病毒）灭活疫苗的免疫原性和安全性。 方法： 于2021年1-2月以山西省太原市405名公安人员为研究对象，通过随机分组将其分为3组，分别按照0~14 d、0~21 d和0~28 d方案接种2剂新冠病毒灭活疫苗，采用RT-PCR检测新冠病毒核酸，活病毒微量病变法检测新冠病毒中和抗体，分析3组的新冠病毒中和抗体GMT、血清阳转率和安全性。 结果： 0~14 d、0~21 d和0~28 d方案组新冠病毒中和抗体血清学阳转率均为100%，其中0~21 d组［166.70（95%CI：148.30~185.10）］和0~28 d组［179.50（95%CI：156.50~202.60）］新冠病毒中和抗体水平接近（P>0.05），均明显高于0~14 d组［86.08（95%CI：72.36~99.80）］（P<0.001）。3个方案组不良反应发生率分别为1.48%（2/135）、0.74%（1/136）和1.49%（2/134）（P=0.750），均为轻度不良反应。 结论： 公安人员按不同方案（0~14 d、0~21 d、0~28 d）接种新冠病毒灭活疫苗后均表现出较好的血清阳转率和安全性，0~21 d和0~28 d接种方案组新冠病毒中和抗体GMT高于0~14 d方案组。.