Clinical analysis of 23 cases of neonatal Omicron (a variant of SARS-CoV-2) infection in Suzhou

Abstract

Objective To analyze the clinical characteristics of neonatal cases of severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection in Suzhou since December 2022. Methods In this retrospective case series study, the clinical data of 23 neonates with SARS-CoV-2 infection at our hospital from December 10, 2022, to January 10, 2023, were collected, and the epidemiological history, clinical manifestations and outcomes, laboratory changes, etc., were analyzed. Results Among the 23 infants, there were 9 males and 14 females, 22 full-term infants, and 1 premature infant (35 weeks+ 1). The oldest was 27 days old, and the youngest was premature. Age at diagnosis was 14(9.0,19.0) days. The mothers were all prenatally diagnosed with coronavirus disease 2019 (COVID-19). All 22 full-term infants lived with their mothers in the same room. Among them, 8 were exclusively breastfed, 14 were mixed-fed, and 1 was a preterm infant who was not breastfed. Twenty-two neonates were infected by horizontal transmission, and 1 was infected by suspected vertical transmission from mother to child. The clinical classification included 1 asymptomatic infection, 20 mild infections, 2 moderate infections. The most common clinical manifestations were fever (21 neonates), and the fever duration was 1–6 days. Other clinical manifestations included respiratory symptoms(18 neonates), digestive tract symptoms(12 neonates) and abdominal distension (2 neonates). Neurological symptoms included mild drowsiness, irritability, and crying (3 neonates). The other symptoms included 4 cases of jaundice and 2 cases of rash. The white blood cell count was lower than 4.0*109/L in 1 neonate. The lymphocyte count was lower than 1.0*109/L in 1 neonate. Interleukin-6 was normal in 3 neonates, slightly elevated in 11 neonates, and greater than 200 pg/ml in 2 neonates. Procalcitonin was slightly elevated in 1 neonate. The creatine phosphokinase isoenzyme (CK-MB) was slightly elevated in 4 neonates. Two neonates had flocculent high-density shadows in chest X-ray. 21 patients were cured and discharged, while another 2 patients were discharged after improvement; the length of hospitalization was 3.8 (4.0,5.0)days. Twenty-one patients were followed up and no repeated clinical manifestations were reported. Conclusion SARS-CoV-2 infection in neonates in this area was mainly transmitted horizontally and mainly mild cases, with mild clinical symptoms and mildly increased inflammatory indicators. The short-term prognosis was good.