Biology 1001A Lecture : Biology notes.docx
Document Summary
Lecture 2: the general mechanisms by which vaccines protect against diseases. Vaccines protect against disease by priming the immune system. They introduce a harmless version of the disease into the body that allows the immune system to gain. Memory of the invader for the next time it encounters the disease. Later, due to priming by the vaccine, the immune system is able to respond faster and with more intensity with antibodies to the real, damaging form of the disease. Why developing a vaccine against hiv is relatively challenging, compared to other diseases. Hiv has a high mutation rate so it changes the markers on its surface too often to develop an effective vaccine. Each time the markers change, the vaccine is useless and the immune system can"t recognize the virus: why people are encouraged to get a flu vaccine each year (as opposed to one time only).