A SARS-CoV-2 familial cluster infection reveals asymptomatic transmission to children

Abstract

Information on SARS-CoV-2 asymptomatic infection and infectivity in children is limited. In this study, we aimed to report the epidemiological and clinical characteristics of a familial cluster infection including children with SARS-CoV-2. On February 1, 2020, two children(case 1 and case 2), an 8-year-old girl and a 9-year-old boy, were admitted to the isolation ward in Xiangyang Central Hospital, Hubei province, China, with the diagnosis of COVID-19. Before admission, they had been staying at home with their father and never contacted with any confirmed patients except their mother (case 3) who returned from Wuhan on January 22. Both case 1 and case 2 got mild symptoms. Case 3 did not develop any symptoms until February 6, 2020, with an asymptomatic period of 15 days. She was transferred to ICU and administered multiple treatment according to the disease progression and chest CT manifestations. Her nucleic acid test turned positive until Feb 21, 2020, 15 days after symptoms onset, 30 days after her return from Wuhan. Our data showed that patients with SARS-CoV-2 may have the ability to transmit during their asymptomatic period even with the negative of viral nucleic acid in pharyngeal swabs.

Keywords: Asymptomatic infections; COVID-19; Children; SARS-CoV-2; Transmission.

Fig. 1

Timeline of COVID-19 cases within a familial cluster in Xiangyang, Hubei Province, China. The mother returned to Xiangyang from Wuhan on Jun.22 and then lived with her family. In the following month, the younger sister, brother, and mother developed COVID-19. The course of symptoms and hospitalization are shown in different colors. RT-PCR, real-time reverse transcription PCR;ICU,intensive care unit. The white box is father, (1), (2) (3) are cases.

Fig. 2

Dynamic changes of case 3 lung CT imaging. Two different scanning layers are displayed at each time point. (A) 8 days after returning from Wuhan: only a small pure GGO (black arrow) in the right lower lobe. (B) 18 days after returning from Wuhan and 3 days after the onset of initial symptoms: more severe lesions with GGO in the dorsal segment of right lower lobe (black arrow). (C) 11 days after the onset of initial symptoms: the predominant pattern of abnormality was consolidation (white arrow), accompanied by a small GGO (black arrow) in the right lower lobes. (D–E) 16 to 20 days after the onset of initial symptoms: the extent of the lesions was reduced with consolidation (white arrow), linear opacities (thick black arrow) and GGO (thin black arrow) in the right lower lobe. (F) 2 days after the clinical symptoms disappeared, only residual pure GGO (black arrow).