1. White Blood Cells
1.1. White blood cells defend your body from germs and infections.
1.2. Killer cells, or phagocytes, destroy invading germs. There are different types.
1.3. Lymphocytes are the cells that remember previous invading viruses or germs. They serve as a memory bank for the killer cells.
1.4. There are two kinds of lymphocytes (B lymphocytes and T lymphocytes).
1.5. B lymphocytes are like the body's intelligence system, seeking out their targets and sending defenses to lock onto them.
1.6. T cells destroy the invaders.
2. Vaccinations: The Story
2.1. Dr Edward Jenner
2.1.1. He is the "Father of Immunology", widely credited with creating the smallpox vaccine, thus saving the lives of many people.
2.1.2. He took a small drop of pus from the hand of a milkmaid called Sara Nelmes, who had the smallpox. He then injected this pus into a eight-year old boy named James Phipps. After six weeks he injected more pus from a smallpox victim into poor James, who was now immune to smallpox. The boy remained healthy and when people heard, they were amazed and asked for the treatment. Dr Jenners became rich and he gave James his own cottage with flowers around the door.
2.2. Louis Pasteur
2.2.1. He developed a rabies vaccine. After this in the nineteenth century it was compulsory to be vaccinated.
2.3. 20th Century
2.3.1. Several major vaccines were developed, like the measle vaccine. The development of the polio vaccine in the 1950s and the eradication of smallpox during the 1960s and 1970s was a major accomplishment.