METHODS: We evaluated anti-spike IgG (Abbott) and neutralising (cPASS/GenScript) antibody (nAb) titers up to one year after mRNA-1273 boost in two-dose-CoronaVac-primed Indonesian healthcare workers (August 2021-August 2022). We used linear mixed modeling to estimate the rate of change in antibody levels, and logistic regression to examine associations between antibody levels and VBI.
RESULTS: Of 138 participants, 52 (37.7%) had a prior infection and 78 (56.5%) received an mRNA-1273 booster. After two-dose CoronaVac, antibody titers had significantly declined within 180 days, irrespective of prior infection. After mRNA-1273 booster, anti-spike IgG (1.47% decline/day) and Omicron B.1.1.529/BA.2 nAbs declined between day 28-90, and IgG titers plateaued between day 90-360. During the BA.1/BA.2 wave (February-March 2022), 34.6% (27/78) of individuals experienced a VBI (median 181 days after mRNA-1273), although none developed severe illness. VBI was associated with low pre-VBI anti-spike IgG and B.1.1.529/BA.2 nAbs, which were restored post-VBI.
CONCLUSIONS: mRNA-1273 booster after two-dose CoronaVac did not prevent BA.1/BA.2 VBI. Periodic vaccine boosters may be warranted against emerging SARS-CoV-2 variants.
方法:我们评估了在两剂CoronaVac引发的印度尼西亚医护人员(2021年8月至2022年8月)中mRNA-1273增强后一年内的抗标IgG(Abbott)和中和(cPASS/GenScript)抗体(nAb)滴度。我们使用线性混合模型来估计抗体水平的变化率,和逻辑回归检查抗体水平和VBI之间的关联。
结果:在138名参与者中,52(37.7%)曾感染过,78(56.5%)接受了mRNA-1273加强剂。两次注射CoronaVac后,抗体滴度在180天内显著下降,不管以前的感染。mRNA-1273加强后,抗标IgG(1.47%/天下降)和OmicronB.1.1.529/BA.2nAbs在第28-90天之间下降,IgG滴度在第90-360天之间趋于稳定。在BA.1/BA.2浪潮期间(2022年2月至3月),34.6%(27/78)的个体经历了VBI(mRNA-1273后中位181天),虽然没有人患上严重疾病。VBI与低VBI前抗尖峰IgG和B.1.1.529/BA.2nAbs相关,在VBI后恢复。
结论:两剂CoronaVac后加强mRNA-1273并不能预防BA.1/BA.2VBI。可能需要定期接种疫苗以对抗新出现的SARS-CoV-2变体。