【摘要】 目的 了解甘肃省人群血清新型冠状病毒（severe acute respiratory syndrome coronavirus 2,SARSCoV-2，简称新冠病毒）IgG抗体水平，为疫情防控提供重要血清学依据。方法 采用整群抽样方法，于2023年2月选取甘肃省14个市/州和兰州新区，每个市/州分别选取2个县/区，按照0～<5、 5～<15、15～<25、25～<60、60～<80、≥80岁6个年龄段进行抽样。对调查对象开展新型冠状病毒感染状况、疫苗接种情况等回顾性调查，同时采集调查对象外周静脉血，用化学发光法检测SARS-CoV-2 IgG抗体。分别采用χ~2检验和Kruskal-Wallis H检验对抗体阳性率和抗体浓度进行统计学分析。结果 有效调查6 238人，出现发热、咽痛等呼吸道症状者5 302人，占85.00%，自诉未发病者303人，占4.86%，不清楚是否发病的占10.15%(633人)。血清SARS-CoV-2 IgG总阳性率为96.31%(6 008/6 238)，抗体浓度（发光值）为66.99(41.83,83.49)。自诉发病组（含确诊）、自诉未发病组和不清楚是否发病组抗体阳性率分别为97.25%(5 156/5 302)、89.11%(270/303)和91.94%(582/633)。各市/州人群抗体阳性率差异有统计学意义（χ~2=87.17,P<0.05）;5～<80岁人群抗体阳性率最高（97.07%,5 174/5 330）,80岁以上老人抗体阳性率最低（90.57%,586/647），各年龄组抗体阳性率差异有统计学意义（χ~2=91.80,P<0.05）；医护人员、学生抗体阳性率较高，分别为98.41%(806/819)和97.87%(1 242/1 269)，不同职业抗体阳性率差异有统计学意义（χ~2=49.25,P<0.05）。完成新冠病毒疫苗接种2剂次及以上者5 775人，占总调查人数的92.58%,5岁以下儿童全程接种率最低（28.74%,75/261），其次为80岁以上老人（85.16%,551/647）,5～<80岁人群全程接种率为96.60%(5 149/5 330)，不同年龄组间疫苗接种率差异有统计学意义（χ~2=1 723.87,P<0.05）。自诉发病组完成接种2剂次及以上者占93.34%(4 949/5 302)，抗体阳性率为97.25%(5 156/5 302)；自诉未发病组全程接种率和抗体阳性率分别为86.47%(262/303)和89.11%(270/303)；自诉不清楚是否发病组全程接种率和抗体阳性率分别为89.10%(564/633)和91.94%(582/633)；自诉发病组、自诉未发病组和不清楚是否发病组疫苗全程接种率和抗体阳性率差异有统计学意义（χ~2=24.13、91.33,P<0.05）。结论 甘肃省人群新冠病毒抗体维持在较高的水平，SARSCoV-2疫苗全程接种率>90%，短期内再次引起人群大规模感染的风险较低。应继续开展人群血清抗体水平动态监测和中和抗体监测及针对目前新的变异株抗体的监测，为新冠病毒疫情防控提供更多依据。更多还原

【Abstract】 Objective To understand the levels of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) IgG antibodies in the population of Gansu province, so as to provide an important serological basis for epidemic prevention and control. Methods Two counties/districts were selected in each of the 14 cities/prefectures in Gansu province and a whole-group stratified sampling was conducted based on 6 age groups: 0-<5, 5-<15, 15-<25, 25-<60, 60-<80 and ≥80. A retrospective investigation was carried out on 6 238 subjects on the status of SARS-COV-2 infection and vaccination among the population. Venous blood samples were collected, and SARS-CoV-2 IgG antibodies were detected using the chemiluminescence method. χ~2 and Kruskal-Wallis H tests were used to analyze the antibody positivity rate and antibody concentration of the subjects. Results A total of 6 238 subjects were effectively surveyed in Gansu province. Among them, 5 302 individuals, accounting for 85. 00%, had respiratory symptoms such as fever and sore throat, while 303 individuals, accounting for 4. 86%, denied symptoms, and 633 individuals, accounting for 10. 15%, were unsure. The total positive rate of serum SARS-CoV-2 IgG was 96. 31%(6 008/6 238), with a median antibody concentration(interquartile range) of 66. 99(41. 83, 83. 49). The antibody-positive rates of the population with onset, denial, and unknown cases were 97. 25%(5 156/5 302), 89. 11%(270/303), and 91. 94%(582/633), respectively. There was significant difference in the antibody-positive rate among the population in different cities and prefectures （χ~2=87. 17, P<0. 05）.The antibody-positive rate of the population aged 5 to <80 was as high as 97. 07%(5 174/5 330), while the antibody-positive rate of the elderly aged 80 and above was the lowest at 90. 57%(586/647). There was a statistically significant difference in antibody-positive rates among different age groups （χ~2=91. 80, P<0. 05）. The antibody-positive rates of medical staff and students were 98. 41%(806/819) and 97. 87%(1 242/1 269), which were higher than those of other professions, and the differences were statistically significant （χ~2=49. 25, P<0. 05）.A total of 5 775 individuals completed two or more doses of SARS-CoV-2 vaccination, accounting for 92. 58% of the total number of people surveyed. The lowest vaccination rate was 28. 74%(75/261) for children under 5 years old, followed by 85. 16%(551/647)for people over 80 years old, and 96. 60%(5 149/5 330) for people between 5 and 79 years old. There were statistically significant differences in vaccination rates among different age groups （χ~2=1 723. 84, P<0. 05）. The full course vaccination rate for the symptomatic group was 93. 34%(4 949/5 302), with an antibody positivity rate of 97. 25%(5 156/5 302); the non-symptomatic group had full course vaccination rate and antibody positivity rate of 86. 47%(262/303) and 89. 11%(270/303) respectively; the unknown group had full course vaccination rate and antibody positivity rate of 89. 10%(564/633) and 91. 94%(582/633) respectively; the differences in full course vaccination rates and antibody positivity rates among the symptomatic group, non-symptomatic group, and unsure group were statistically significant （χ~2=24. 13, 91. 33, P<0. 05）.Conclusions The population in Gansu province maintain a high level of SARS-COV-2 antibodies, with a full course vaccination rate for SARS-CoV-2 exceeding 90%, indicating a low risk of large-scale infections in the short term. Continuous monitoring of serological antibody levels in the population and surveillance of neutralizing antibodies against new variants are recommended to provide further basis for the prevention and control of the COVID-19 epidemic.更多还原