Features
Implications
- Innate immune system is muted at birth and matures with increasing age
- Newborns and young infants relatively susceptible to bacterial and viral infections
- Allows the foetus to tolerate non-shared maternal antigens
- The adaptive immune system is immature, providing increased protection over time with accumulation of immunological memory
- Neonates and young infants receive IgG antibody transfer from the mother transplacentally and in breast milk
- Passive IgG antibodies provide some protection against infection
- Young children become more vulnerable to infections when passive IgG transfer stops until immune memory matures