河南省SARS-CoV-2既往感染与再次感染人群抗体水平分析

Anti-SARS-CoV-2 antibody levels in previously infected and re-infected populations in Henan Province,China

目的回顾分析2022年1月河南省郑州市-禹州市COVID-19疫情(首次感染变异株为Delta/B.1.617.2)和安阳市疫情(首次感染变异株为Omicron/BA.1.1)中既往SARS-CoV-2感染者的再感染水平及人群特征,并分析不同感染人群的抗体水平。方法共采集371例既往感染者、134例再次感染者和19例未感染者的血清样本进行IgG抗体检测。其中45例既往感染者、44例再次感染者和19例未感染者的血清样本采用不同SARS-CoV-2变异株(早期原始毒株、BA.5.2变异株、XBB.1.5变异株)进行中和抗体检测。结果郑州市-禹州市COVID-19疫情中再次感染率为32.82%(85/259),安阳市疫情中再次感染率为19.92%(49/246)。再次感染人群IgG抗体水平高于既往感染人群和未感染人群(P<0.05);未感染人群中3个月内疫苗接种人群IgG抗体水平高于疫苗接种超过6个月的人群(P<0.05);接种4剂疫苗人群IgG抗体水平高于接种3剂疫苗人群(P<0.05)。真病毒中和抗体检测结果显示,郑州市-禹州市疫情中,既往感染和再次感染人群的抗早期原始毒株中和抗体水平均高于抗BA.5.2变异株和抗XBB.1.5变异株中和抗体水平(P<0.05),抗BA.5.2变异株中和抗体水平均高于抗XBB.1.5变异株中和抗体水平(P<0.05)。安阳市疫情中,既往感染人群中抗早期原始毒株中和抗体水平高于抗BA.5.2变异株中和抗体水平和抗XBB.1.5变异株中和抗体水平(P<0.05);再次感染人群中,抗早期原始毒株中和抗体说高于抗XBB.1.5变异株中和抗体水平(P<0.05)。此外,既往感染和再次感染人群各中和抗体水平均大于未感染人群(P<0.05);郑州市-禹州市疫情感染人群中抗早期原始毒株中和抗体水平高于安阳市疫情感染人群和未感染人群(P<0.05),郑州市-禹州市疫情感染人群中抗BA.5.2变异株和抗XBB.1.5变异株中和抗体水平均高于未感染人群(P<0.05);安阳市疫情感染人群中既往感染人群抗BA.5.2变异株中和抗体水平高于未感染人群(P<0.05),安阳市疫情感染人群中抗XBB.1.5变异株中和抗体水平高于未感染人群(P<0.05)。结论感染SARS-CoV-2后,人体内产生的中和抗体对SARS-CoV-2变异株具有一定的交叉保护作用,但抗体水平会随着时间逐渐降低。感染早期变异株产生的中和抗体对Omicron变异株(如XBB变异株)的保护作用已经大大下降,既往感染或加强接种引起的免疫力可能不足以抵抗新变异株感染。

ObjectiveTo analyze the reinfection rates in people previously infected with SARS-CoV-2 in Zhengzhou and Yuzhou cities(first infected with Delta/B.1.617.2 variant),and Anyang city(first infected with Omicron/BA.1.1 variant)in January 2022 and the population characteristics,and compare the differences in antibody levels among different populations.MethodsSerum samples were collected from 371 previously infected,134 reinfected and 19 uninfected people for IgG antibody detection.Among them,serum samples from 45 previously infected,44 reinfected and 19 uninfected people were tested with different novel coronavirus variants(early original strain,BA.5.2 variant,XBB.1.5 variant)for neutralizing antibody detection.ResultsThe rate of reinfection was 32.82%(85/259)in Zhengzhou and Yuzhou cities,and 19.92%(49/246)in Anyang city.The IgG antibody level in reinfected people was higher than that in previously infected and uninfected people(P<0.05).The IgG antibody level in uninfected group was higher in people vaccinated within three months than in those vaccinated six months ago(P<0.05).The IgG antibody level in the group receiving four doses of vaccine was higher than that in the group receiving three doses of vaccine(P<0.05).The results of true virus neutralization antibody detection showed that in the Zhengzhou and Yuzhou cases,the level of neutralization antibody against the early original strain was higher than those against the BA.5.2 variant and the XBB.1.5 variant(P<0.05),and the level of neutralizing antibody against BA.5.2 variant was higher than that against XBB.1.5 variant(P<0.05).In Anyang city cases,the level of neutralizing antibody against the early original strain was higher than those against BA.5.2 variant and XBB.1.5 variant(P<0.05);in the reinfected population,the level of neutralizing antibody against the early original strain was higher than that against the XBB.1.5 variant(P<0.05).In addition,the levels of all neutralizing antibodies in both previously infected and reinfected people were higher than those in uninfected people(P<0.05).The level of neutralizing antibody in the infected population in Zhengzhou and Yuzhou cities was higher than that in the infected population in Anyang city and in uninfected population(P<0.05).The levels of antibodies against BA.5.2 and anti-XBB.1.5 variants in infected people in Zhengzhou and Yuzhou cities were higher than those in uninfected people(P<0.05).The level of neutralizing antibody against BA.5.2 variants in the previously infected population in Anyang city was higher than that in the uninfected population(P<0.05),and the level of neutralizing antibody against XBB.1.5 variants in the infected population in Anyang city was higher than that in the uninfected population(P<0.05).ConclusionsAfter infection with SARS-CoV-2,the neutralizing antibodies produced in the human body have a certain cross-protection effect on other variants,but the antibody level will gradually decrease over time.Protection from a previous early SARS-CoV-2 variants infection against the current main circulating Omicron variants(such as XBB variants)is low,and the immunity conferred by pervious infection or booster vaccination may not be able to provide sufficient protection against new variants.