Why is a baby’s immune system different?
When a baby is born, it has certain antibody- like proteins called immunoglobulins, which it has received through the placenta. Another very important one is received from its mother after it is born. This immunoglobulin is called IgA and is present in the colostrum, the first part of mother’s milk. It places itself on the mucus membranes of the baby’s alimentary canal in order to help fight the bacteria that can cause gastroenteritis. Babies do not start to produce their own IgA until around 6 months of age.
