Vaccines
- Edward Jenner founded the idea of vaccination. He realised that people who got cowpox didn’t get smallpox. In 1796 Jenner took pus from a cowpox blister and rubbed it into the skin of an 8-year-old boy. He got a mild fever but that was all. He did the same with the pus from a smallpox blister. He didn’t get smallpox. The cowpox vaccine had made him immune to smallpox.
- Smallpox is caused by a virus. All viruses and cells have chemicals on their outer surfaces called antigens. Our bodies can recognise foreign antigens and therefore try to destroy these foreign antigens and cells.
- A vaccine contains a harmless version of a pathogen or parts of it. Your body recognises it as a foreign body and your immune system kicks into action. B-lymphocytes respond to the pathogen by producing antibodies. By trial and error, the antibody that fits the antigen on the pathogen is found. Once this happens, the B-Lymphocytes produce it in large numbers.
- Some of these lymphocytes become memory lymphocytes. The way the body responds to infection is called the immune response. Making someone immune to a disease is called immunisation.
Are vaccines safe?
- All young children in the UK are offered vaccinations to dangerous childhood diseases such as measles and whooping cough. However, sometimes children can get a reaction to the vaccine.
- About 20% of children may get a mild fever or a rash from the measles vaccine and 1 in a million get a dangerous reaction.
- Due to media scares about the risks of immunisation, many parents are persuaded not to have their children immunised.
