Detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfections is challenging with current serology assays and is further complicated by the marked decrease in routine viral testing practices as viral transmission increased during Omicron. Here, we provide proof-of-principle that high-avidity anti-nucleocapsid (N) antibodies detects reinfections after a single infection with higher specificity (85%; 95% confidence interval [95% CI], 80%–90%) compared to anti-N antibody levels (72%; 95% CI, 66%–79%) in a vaccinated cohort. This method could be used to retroactively investigate the epidemiology and incremental long-term health consequences of SARS-CoV-2 reinfections.

中文翻译：

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一种用于识别 SARS-CoV-2 再感染的新型抗核衣壳抗体亲和力方法

使用当前的血清学检测检测严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 再次感染具有挑战性，并且由于 Omicron 期间病毒传播增加，常规病毒检测实践显着减少，这使情况变得更加复杂。在这里，我们提供了原理证明，表明高亲和力抗核衣壳 (N) 抗体能够以更高的特异性（85%；95% 置信区间 [95% CI]，80%–90%）检测单次感染后的再感染。疫苗接种队列中的抗 N 抗体水平（72%；95% CI，66%–79%）。该方法可用于追溯调查 SARS-CoV-2 再次感染的流行病学和增量长期健康后果。