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By Mayo Clinic staffChickenpox was once considered a rite of passage for most children. Before the vaccine became available, about 4 million children in the Unites States contracted chickenpox each year, and nearly 11,000 people were hospitalized and about 100 people died each year from chickenpox infections. Thanks to the vaccine, the number of cases and hospitalizations is down dramatically.
However, when chickenpox does occur, it's highly contagious among people who aren't immune. Most people think of chickenpox as a mild disease — and, for most, it is. But, there's no way to know which infected child or adult will develop a severe case.
Fortunately, the chickenpox vaccine is a safe, effective way to prevent chickenpox and its possible complications.