背景:SARS-CoV-2病毒载量在预测传染性中的作用,疾病严重程度,可传播性,和临床决策仍然是一个非常感兴趣的领域。然而,大多数研究是在成人中进行的,并使用循环阈值(Ct)值评估了SARS-CoV-2负荷,这些都不是标准化的,阻止了对理解临床影响和效用至关重要的一致解释。这里,2020年3月28日至2022年1月31日,在圣裘德儿童研究医院对诊断为COVID-19的有严重疾病风险的儿童进行了标准化的SARS-CoV-2逆转录数字PCR(RT-dPCR)定量检测。
方法:来自儿童的人口统计学和临床信息,我们从病历中提取了在圣裘德儿童研究医院接受治疗的青少年和年轻人.呼吸道样本通过RT-dPCR靶向N1和N2基因进行SARS-CoV-2RNA定量,进行测序以确定感染病毒的遗传谱系。
结果:研究期间纳入了46例0-24岁(中位年龄11岁)的患者。大多数患者感染了omicron变异体(43.72%),其次是祖先菌株(22.29%),delta(13.20%)和alpha(2.16%)。呈递时的病毒载量范围为2.49至9.14log10IU/ml,和较高的病毒RNA载量与症状(OR1.32:CI95%1.16-1.49)和呼吸系统疾病(OR1.23:CI95%1.07-1.41)相关。SARS-CoV-2变体的病毒载量没有差异,疫苗接种状况,年龄,或基线诊断。
结论:SARS-CoV-2RNA负荷可预测症状性疾病和呼吸系统疾病的存在。使用标准化,定量方法是可行的,允许复制,跨机构的比较,并有可能促进风险分层和治疗的共识定量阈值。
BACKGROUND: The role of SARS-CoV-2 viral load in predicting contagiousness, disease severity, transmissibility, and clinical decision-making continues to be an area of great interest. However, most studies have been in adults and have evaluated SARS-CoV-2 loads using cycle thresholds (Ct) values, which are not standardized preventing consistent interpretation critical to understanding clinical impact and utility. Here, a quantitative SARS-CoV-2 reverse-transcription digital PCR (RT-dPCR) assay normalized to WHO International Units was applied to children at risk of severe disease diagnosed with COVID-19 at St. Jude Children\'s Research Hospital between March 28, 2020, and January 31, 2022.
METHODS: Demographic and clinical information from children, adolescents, and young adults treated at St. Jude Children\'s Research Hospital were abstracted from medical records. Respiratory samples underwent SARS-CoV-2 RNA quantitation by RT-dPCR targeting N1 and N2 genes, with sequencing to determine the genetic lineage of infecting virus.
RESULTS: Four hundred and sixty-two patients aged 0-24 years (median 11 years old) were included during the study period. Most patients were infected by the omicron variant (43.72%), followed by ancestral strain (22.29%), delta (13.20%), and alpha (2.16%). Viral load at presentation ranged from 2.49 to 9.14 log10 IU/mL, and higher viral RNA loads were associated with symptoms (OR 1.32; CI 95% 1.16-1.49) and respiratory disease (OR 1.23; CI 95% 1.07-1.41). Viral load did not differ by SARS-CoV-2 variant, vaccination status, age, or baseline diagnosis.
CONCLUSIONS: SARS-CoV-2 RNA loads predict the presence of symptomatic and respiratory diseases. The use of standardized, quantitative methods is feasible, allows for replication, and comparisons across institutions, and has the potential to facilitate consensus quantitative thresholds for risk stratification and treatment.