Is there any chance for measles after vaccination?

Of course, because..: Life is not perfect, and vaccinations are not 100% protective (but they are so so much better than catching the disease). A measles vaccine given to an infant may not give long lasting immunity, so we give 1 shot after age 12-15 months and a second shot after age 4 yrs. If we give only a single shot, the antibodies don't last as long and the person may still be able to catch measles in the future.