To investigate the clinical features and treatment of chickenpox in newborns.

Total of 26 neonates with chickenpox admitted to Beijing Ditan Hospital, Capital Medical University from January 2014 to December 2019 were enrolled for retrospective analysis (neonatal group), and 52 infants aged 1-3 months were enrolled according to a sex ratio 1︰2 during the same period (infant group). The perinatal data, birth history, epidemiological history, clinical manifestations, complications, biochemical indicators and treatments of the two groups were analyzed, retrospectively. Statistical analysis were performed by two independent samples t-test, rank-sum test and Chi-square test.

The mean age of onset of cases in neonatal group and infant group [(9.42 ± 4.10) days vs. (64.29 ± 14.59) days] were significantly different (t = 18.75, P < 0.001); but gender, proportion of preterm infants, mean birth weight, mean Apgar score and amniotic fluid feces staining of cases in the two groups were not significantly different (all P > 0.05). In terms of epidemiological history, the proportion of vertical transmission (χ² = 57.474, P < 0.001) and horizontal transmission (χ² = 53.337, P < 0.001) in two groups were significantly different. Between chickenpox cases in neonatal group and infant group, the raio of rash eruption from face (χ² = 3.900, P = 0.048), vomiting (χ² = 3.989, P = 0.046), viral encephalitis (χ² = 7.313, P = 0.007) and viral pneumonia (χ² = 8.432, P = 0.004) were significantly different; However, fever duration, number of fever cases, other eruption order, skin infection, skin scab duration and cellulitis were not significantly different (all P > 0.05). The levels of alanine aminotransferase (ALT) [34.5 (26.0, 87.0) g/L vs. 27.0 (22.0, 33.0) g/L: Z = 2.21, P = 0.027] and aspartate aminotransferase (AST) [38 (22.0, 88.0) g/L vs. 26.5 (22.0, 33.0) g/L: Z = 2.38, P = 0.017] were significantly different; but there were no significant differences in the number of granulocyte deficiency, thrombocytopenia, liver function abnormalities, myocardial enzyme abnormalities, leukocyte count, lymphocyte percentage, percentage of neutrophils, platelet count, albumin and creatine kinase isoenzyme (CK-MB) (all P > 0.05). Cases in two groups were all isolated in single room, with interferon gel for erythra and iodophors for pox to avoid skin infection. Mothers who had chickenpox before or during labor delivered in the negative pressure isolation ward, and neonatus were isolated from their mothers after delivery, inorder to reduce postpartum respiratory transmission. Children complicated with pneumonia and encephalitis were treated with intravenous human immunoglobulin (400 mg·kg^-1·d^-1) and acyclovir (10 mg kg^-1·time^-1, 3 times/d). Both groups of children with chickenpox were all cured and discharged.

The main infection routes of neonatal chickenpox are vertical transmission from mothers or horizontal transmission from brothers or sisters. The clinical features are mainly vomit and rashes all over the body. The order of rash may be atypical. The symptoms of fever maybe not obvious, mainly due to the underdeveloped organs after birth, so more newborns were complicated with viral pneumonia or viral encephalitis. The treatment is mainly focused on single room isolation and symptomatic treatment. Children with complications can be treated with intravenous human immunoglobulin and acyclovir, with good prognosis.