The other 2 arteries that bring blood to the brain, called the vertebral arteries, supply the brainstem. Plaque in the vertebral arteries is much less likely to break off and cause a stroke, but narrowing in the vertebral arteries can cause problems if the brainstem does not get enough blood flow.
A child should receive the first shot when he is between 12-15 months, and the second when he's between 4-6 years of age. If you're not sure if you have had the diseases or the vaccines (prior to 1971 it was given in three separate shots), you can get the MMR vaccine as an adult.
1 People who cannot show that they were vaccinated as children and who have never had measles should be vaccinated. 2  Infants 6-11 months of age should have 1 dose of measles vaccine if traveling internationally. 3  Children in the United States routinely receive measles vaccination at 12-15 months of age.