Maybe. If unimmunized kids are exposed to any of these diseases, there’s a good chance they’ll get the disease. What happens then depends on the child and the disease. At the least, some kids could get a mild rash and have to stay home from child care or school for a few days. On the other hand, some kids may become sick enough to be hospitalized, suffer a permanent disability, or die.
Those diseases are highly contagious and can be transmitted through body fluids, saliva particles in the air or even contaminated food and drinks.