Immunoglobulin transmission to infants born to mothers with COVID-19.

Background: COVID-19 infection is a severe condition in pregnant women. Previous studies have suggested that anti-COVID-19 antibodies may be able to be transmitted from mother to fetus, which in itself is a protective factor in infants against the disease. However, few studies have been done in this area. In the present study, we aimed to investigate the presence of anti-COVID-19 antibodies in infants born to symptomatic and asymptomatic mothers with positive COVID-19 test.

Methods: This is a cross-sectional study performed in 2021 in Abadan on neonates, born to symptomatic and asymptomatic mothers with positive COVID-19 test. All pregnant women over the age of 38 weeks with positive PCR tests for COVID-19 were included. We collected five cc of blood from the umbilical cord of neonates immediately after birth. The samples were sent to the laboratory in laboratory tubes to measure the anti-COVID-19 IgM and IgG levels.

Results: We evaluated data of 20 neonates born to mothers with symptomatic COVID-19 and 10 neonates born to asymptomatic mothers with positive COVID-19 tests. In symptomatic groups, sixteen neonates (80%) had positive IgG antibodies and the mothers of all these neonates had positive antibodies. The mean IgG levels in infants was 73.26 ± 12.54 RU/ml and the mean IgM levels were 14.29 ± 3.71 RU/ml. Among neonates born to mothers with no symptoms, 7 neonates (70%) had positive IgG antibody. All mothers had positive antibodies. The mean IgG levels in infants were 74.50 ± 11.37 RU/ml and the mean IgM levels was 12.49 ± 2.88 RU/ml. There were no significant differences between two groups of neonates regarding positivity of IgG and antibody levels (P>0.05 for all).

Conclusion: 80% of infants born to mothers with COVID-19 pneumonia had positive IgG levels that were in line with the previous reports.