Humoral cross-reactivity towards SARS-CoV-2 in young children with acute respiratory infection with low-pathogenicity coronaviruses

SARS-CoV-2 infection in children frequently leads to only asymptomatic and mild infections. It has been suggested that frequent infections due to low-pathogenicity coronaviruses in children, imparts immunity against SARS-CoV-2 in this age group. From a prospective birth cohort study prior to the pandemic, we identified children (n=42) with proven low-pathogenicity coronavirus infections. Convalescent sera from these samples had antibodies against the respective seasonal CoVs as demonstrated by immunofluorescence assay. We tested these samples for neutralization of SARS-CoV-2 using virus microneutralization assay. Forty serum samples showed no significant neutralization of SARS-CoV-2, while 2 samples showed inconclusive results. These findings suggest that the antibodies generated in low-pathogenicity coronavirus infections offer no protection from SARS-CoV-2 infection in young children.

The association of maternal postpartum depression with infant weight growth: a prospective birth cohort study

Background Untreated maternal postpartum depression has consequences for infant weight, which may vary with infant growth time and postpartum depression duration. Dynamic assessment of the association between maternal postpartum depression and infant weight growth is crucial for early detection of the suspicious abnormal effects of maternal postpartum depression on infant weight growth and taking corresponding intervention measures. But, none of published studies continuously and dynamically evaluated these effect changes on infant weight growth. This study was aimed to evaluate the dynamic effects of maternal postpartum depression on infant weight growth at a prospective birth cohort. Methods 960 mother-infant pairs between 2015 to 2018 in Changsha, China were followed up at ages of 1, 3, 6, 8, and 12 months. Data were obtained through household surveys. Depression of mothers was assessed at 1 month postpartum. Linear mixed models and generalized estimating equation models were used to test the connection and its changes between maternal postpartum depression and infant weight growth at five different periods of 1–12 months. Results 8.0% of mothers reported postpartum depression. Adjusted linear mixed models showed a negative association between maternal depression at 1-month postpartum and infant weight at 1 month, 1–3 months, 1–6 months, 1–8 months, and 1–12 months, in which infants with depressed mothers were the lighter weight of 0.14kg (95%CI:0.02, 0.25), 0.13kg (95%CI:0.02, 0.24), 0.13kg (95%CI:0.02, 0.24), 0.13kg (95%CI:0.02, 0.24), and 0.16kg (95%CI:0.04, 0.27) relative to not depressed respectively. Generalized estimating equation models showed a positive association between maternal depression at 1-month postpartum and infant underweight at 1 month and 1–3 months, in which infants of maternal depression had higher risk ratio of underweight in 3.19 (95%CI:1.38, 7.34) and 3.19(95%CI:1.32, 7.70) compared to those mothers were not depressed accordingly. Conclusions Maternal postpartum depression was continuously associated with a lighter weight of ifants from 1 to 12 months and higher risk of being underweight in infants from 1 to 3 months. It seems important to put early prevention, screening, diagnosis, and treatment of maternal depression into practice as soon as possible to avoid adverse consequences.