Department of Paediatrics and Adolescent Medicine, Turku University Hospital and University of Turku.
Department of Biostatistics, Turku University Hospital and University of Turku.
J Infect Dis. 2024 Oct 16;230(4):e837-e846. doi: 10.1093/infdis/jiae278.
Comparative data are limited on the transmission of respiratory infections positive and negative for SARS-CoV-2 in households with children.
In June to August 2020, we recruited 700 participants (175 households, 376 children, 324 adults) to be prospectively followed for all respiratory tract infections. Follow-up lasted from recruitment until April 2022. Daily symptoms were monitored by weekly electronic questionnaires. SARS-CoV-2 polymerase chain reaction testing from nasopharyngeal specimens was performed for symptomatic participants and twice (1-week interval) for the household members of positive participants. Clinical features and secondary attack rates (SARs) based on the onset of symptoms were compared between respiratory infections that were SARS-CoV-2 positive and negative.
Most SARS-CoV-2 infections (90%) occurred from January to April 2022 when Omicron BA.1 and BA.2 were the dominant variants. SARS-CoV-2-positive infections were transmitted more often than SARS-CoV-2-negative infections (SAR, 41% vs 24%; P < .001). SARS-CoV-2 transmission was similar for child and adult index cases (SAR, 40% vs 43%; P = .47), but the transmission of SARS-CoV-2-negative infections was higher for child index cases (SAR, 27% vs 18%; P < .001).
Our findings demonstrate that SARS-CoV-2 Omicron viruses spread more effectively within households as compared with other respiratory infections.
关于儿童家庭中 SARS-CoV-2 阳性和阴性呼吸道感染的传播，比较数据有限。
2020 年 6 月至 8 月，我们招募了 700 名参与者（175 户家庭，376 名儿童，324 名成人），前瞻性随访所有呼吸道感染。随访时间从招募开始持续到 2022 年 4 月。每周通过电子问卷监测每日症状。对有症状的参与者进行鼻咽标本的 SARS-CoV-2 聚合酶链反应检测，对阳性参与者的家庭成员进行两次（间隔 1 周）检测。比较 SARS-CoV-2 阳性和阴性呼吸道感染的临床特征和继发感染率（SAR）。
大多数 SARS-CoV-2 感染（90%）发生在 2022 年 1 月至 4 月，当时奥密克戎 BA.1 和 BA.2 是主要变体。SARS-CoV-2 阳性感染比 SARS-CoV-2 阴性感染更常发生（SAR，41%比 24%；P<0.001）。儿童和成人的首发病例中 SARS-CoV-2 的传播情况相似（SAR，40%比 43%；P=0.47），但儿童首发病例中 SARS-CoV-2 阴性感染的传播率更高（SAR，27%比 18%；P<0.001）。
我们的研究结果表明，与其他呼吸道感染相比，奥密克戎病毒在家庭中传播更有效。
