What is the history of measles?
Cases of measles were described as early as the seventh century. However, it was not until 1963 that researchers first developed a vaccine to prevent measles. Before the vaccine was made available, almost every child became infected with the virus because it is so easily spread. Before routine vaccination, there were approximately 3-4 million cases of measles and 500 deaths due to measles each year in the United States of America. There were initially two types of vaccines developed against measles. One was developed from a virus that had been killed, and the other was developed using a live measles virus that was weakened (attenuated) and could no longer cause the disease. Unfortunately, the killed measles virus (KMV) vaccine was not effective in preventing people from getting the disease, and its use was discontinued in 1967. The live virus vaccine has been modified a number of times to make it safer (further attenuated) and today is extremely effective in preventing the disease. The
