[Asymptomatic SARS-CoV-2 infection in children: a clinical analysis of 20 cases].

OBJECTIVE

To study the clinical and epidemiological features of children with asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

METHODS

The clinical data of 20 children who were diagnosed with asymptomatic SARS-CoV-2 infection from January 20 to March 4, 2020 were analyzed.

RESULTS

Among the 20 children, there were 7 boys (35%) and 13 girls (65%), aged 8 months to 14 years (mean 8±5 years). All these children had no clinical manifestations and attended the hospital for an epidemiological history of SARS-CoV-2. Nineteen children were shown with family aggregation of SARS-CoV-2 infection. Nasopharyngeal swabs were PCR-positive for SARS-CoV-2 in all 20 children. There were 4 children (20%) of mild type, 16 children (80%) of common type, and no children of severe type or critical type. The mean peripheral blood leukocyte count was (6.8±3.5)×109/L, and 7 children had an abnormal peripheral blood leukocyte count, with an increase in 5 children and a reduction in 2 children. One child had a decreased absolute value of lymphocytes (0.87×109/L), 3 children had an increased erythrocyte sedimentation rate (20-42 mm/h), 7 children had an increased lactate dehydrogenase level (>400 U/L), and 4 children had an increased blood lactate level (>1.6 mmol/L). Chest CT showed single or multiple small nodule shadows, patchy shadows, and ground-glass shadows in the middle or lateral lobe of lungs or under the pleura in 13 children.

CONCLUSIONS

Pediatric cases of asymptomatic SARS-CoV-2 infection mostly occur with family aggregation. Most of the children with asymptomatic infection have no obvious abnormalities in blood routine and other laboratory tests. Changes in chest CT scan can be used as an aid for early diagnosis of asymptomatic infection in children.