The Tdap vaccine is used to prevent the serious health consequences that result from tetanus, diphtheria and pertussis diseases. The Center for Disease Control offers the following information about each of these diseases:
Tetanus, also known as lockjaw, enters the body through cuts, scratches or wounds. It causes painful muscle spasms and stiffness, usually all over the body. It can lead to tightening of muscles in the head and neck so the victim cannot open his mouth or swallow, or sometimes even breathe. Tetanus kills about one out of five people who are infected.