When should the measles vaccine be given? How effective is it?
Dr. Greene’s Answer:
The measles vaccine is an effective vaccine in preventing measles. After 2 doses of the measles vaccine, over 99% of recipients will be immune to measles. The initial dose of the measles vaccine is usually administered after a child is 12 months of age. The second dose is recommended at the age of kindergarten entry (i.e. age 4-6 years), but may be given any time 1 month after the first dose. In areas where measles is very common, the vaccine can be given as young as 6 months of age, but protection is suboptimal. In these children, repeat vaccination at 12-15 months and 4-6 years is recommended. When the vaccine is not completely effective, it at least minimizes the length, and particularly the severity, of the disease.
Measles has been a major cause of suffering and death at least since the societies of ancient China, Persia, and Rome. Measles epidemics ravaged Europe throughout the Middle Ages, and attacked the Americas beginning in 1657. Before the measles vaccine became generally available in 1965, there were 3 to 9 million cases of measles in the United States each year. It was a common cause of pneumonia, blindness, seizures, brain damage and death. From 1997-2004, the incidence of measles in the United States ranged from 37-116 cases per year (Redbook 2006), and serious complications are far less common. In developing countries, however, measles is still widespread, infecting almost all unimmunized children by the age of 4. The mortality rate in unimmunized children remains about 10%, and blindness is common if the child is unimmunized and malnourished.