It has been observed that despite the availability of the vaccine for hepatitis a in the market it may not be necessary to be given to children by the time they are 5 years old. why?

Why do leaves change color in the fall? green pigments break down and no longer mask the color of chlorophyll. chlorophyll breaks down and no longer masks the colors of other pigments. red- and yellow-colored pigments grow and mask green-colored chlorophyll. green-colored chlorophyll breaks down and turns red and yellow.