Travels to lymph node where subsequent events happen. For most diseases, if you survive the first week you'll start to get better. Immunization and Vaccines Goal of immunization is to challenge your body with antigen without causing significant disease. Then inject into body, hope it will still resemble natural pathogen enough to stimulate useful antibodies.
Some vaccines take long time to develop.
Jonas Salk spent 10 years trying to develop useful killed vaccine for polio. When the body s immune system turns on itself Involves loss of self-tolerance. All the body s cells include surface markers which tells the immune system that those cells belong there. This is why organ transplants would normally be rejected by the new host body, so the host has to take immunosuppressive drugs. Examples of autoimmune disease include multiple sclerosis, rheumatoid arthritis and Lupus.