Passive Immunity & Breastfeeding (Cambridge (CIE) O Level Biology): Revision Note

Passive Immunity & Breastfeeding

• Passive immunity is a fast-acting, short-term defence against a pathogen by antibodies acquired from another individual

• Before birth, antibodies can be transmitted across the placenta from other to fetus

• After the birth of an infant, antibodies pass from mother to infant via breast milk which contains some white blood cells that can themselves produce antibodies

  • This is important as it helps the very young to fight off infections until they are older and stronger and their immune system is more responsive

• The baby does not make its own antibodies or memory cells in passive immunity, hence the name

• The lack of memory cells explains why passive immunity is temporary