[Clinical characteristics of neonates infected with the Omicron variant of SARS-CoV-2: a multicenter cross-sectional survey].

OBJECTIVES

To investigate the clinical characteristics of neonates infected with the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

METHODS

A cross-sectional survey was conducted on 542 hospitalized neonates with confirmed coronavirus disease 2019 (COVID-19) in 27 hospitals in Shenzhen from December 7, 2022, to January 12, 2023 (during the Omicron variant epidemic period). The neonates were divided into two groups: asymptomatic infection and symptomatic infection. The clinical characteristics, results of laboratory examination, chest X-ray findings, and outcome were compared between the two groups.

RESULTS

Among the 542 neonates, there were 285 males and 257 females. Among them, 515 (95.0%) were full-term infants, and 27 (5.0%) were preterm infants. The asymptomatic infection group had 60 cases, and the symptomatic infection group had 482 cases. Among them, 336 cases (69.7%) were mild, 125 cases (25.9%) were moderate, 15 cases (3.1%) were severe, and 6 cases (1.2%) were critical. Fever was the most common symptom (434 cases, 90.0%), followed by cough and/or spitting (183 cases, 38.0%), nasal congestion and/or runny nose (131 cases, 27.2%), shortness of breath (36 cases, 7.5%), and feeding intolerance (30 cases, 6.2%). Among the 325 cases who underwent chest X-ray examination, 136 cases (41.8%) had patchy or consolidative shadows in the lungs, 2 cases (0.6%) had pneumothorax, 2 cases (0.6%) had decreased lung transparency, and 185 cases (57.0%) showed no abnormality. Among the 396 cases (73.1%) who received treatment, 341 cases (86.1%) received symptomatic treatment, 137 cases (34.6%) received antibiotic treatment, 4 cases (1.0%) received immunoglobulin treatment, and 23 cases (5.8%) received respiratory support treatment. All 542 neonates were discharged from the hospital after their clinical symptoms were relieved, and the median hospital stay was 5 days. The white blood cell count, neutrophil count, hemoglobin, and procalcitonin were lower in the symptomatic infection group than those in the asymptomatic infection group (<0.05), while the platelet count and blood glucose levels were higher in the symptomatic infection group than those in the asymptomatic infection group (<0.05). The proportions of neonates with decreased neutrophil count, increased platelet count, and decreased hemoglobin concentration were higher in the symptomatic infection group than those in the asymptomatic group (<0.05).

CONCLUSIONS

Most neonates with COVID-19 caused by the Omicron variant of SARS-CoV-2 are mild, with fever as the predominant symptom. Symptomatic neonates with COVID-19 are often accompanied by decreased neutrophil count, increased platelet count, and decreased hemoglobin level. Symptomatic treatment is the main treatment, and the prognosis is good.