The aim of this prospective study was to assess the duration of culture-viable SARS-CoV-2 and to monitor the emergence of mutations in a cohort of 23 kidney transplant recipients (KTRs) from June 2022 to June 2023. Combined nares/oropharyngeal swabs were collected weekly starting as soon as possible after symptom onset. The time from symptom onset to a negative culture was 11 days (interquartile range, 8-14), while the time to negative reverse transcriptase quantitative polymerase chain reaction was 18 days (interquartile range, 15-30). Beyond the first swab, 21.7% had a positive culture, and 8.7% replicated viable virus for longer than 30 days. T cell depletion (rate ratio, 2.5; 95% confidence interval [95% CI], 1.9-3.3; P < .001) and time from transplantation (rate ratio, 0.93; 95% CI, 0.90-0.97; P = .006) were associated with the time of viable virus shedding. A cycle threshold value of 24.2 demonstrated a 91.3% negative predictive value of viability (95% credible interval [95% CrI], 76-100). The odds of viability decreased by 69% per week of infection (odds ratio, 0.31; 95% CrI, 0.12-0.76). Overall, ribonucleic acid sequencing did not show accelerated molecular evolution though mutation rate could be increased in molnupiravir-treated KTRs. In conclusion, viable SARS-CoV-2 is eliminated rapidly, the risk of virus evolution is low, and prolonged self-isolation is generally unnecessary for most KTRs.

中文翻译：

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Omicron 时代肾移植受者长期 SARS-CoV-2 脱落和分子进化的风险低：一项前瞻性观察研究


这项前瞻性研究的目的是评估培养可行的 SARS-CoV-2 的持续时间，并监测 2022 年 6 月至 2023 年 6 月期间 23 名肾移植受者 （KTR） 队列中突变的出现。症状出现后尽快开始每周收集鼻孔/口咽联合拭子。从症状出现到培养阴性的时间是 11 天 （四分位距，8-14），而逆转录酶定量聚合酶链反应阴性的时间是 18 天 （四分位距，15-30）。除了第一次拭子检测后，21.7% 的患者培养阳性，8.7% 的患者复制活病毒的时间超过 30 天。T 细胞耗竭 （比率比，2.5;95% 置信区间 [95% CI]，1.9-3.3;P < .001） 和移植时间 （比率，0.93;95% CI，0.90-0.97;P = .006） 与活病毒脱落的时间相关。循环阈值 24.2 表明活力的阴性预测值为 91.3% （95% 可信区间 [95% CrI]，76-100）。感染每周存活率降低 69% （比值比，0.31;95% CrI，0.12-0.76）。总体而言，核糖核酸测序未显示分子进化加速，尽管在 molnupiravir 处理的 KTR 中突变率可能会增加。总之，活的 SARS-CoV-2 被迅速消除，病毒进化的风险很低，并且大多数 KTR 通常不需要长时间的自我隔离。