...which has a much higher morbidity rate. Here's a fascinating article on chickenpox in the U.S. where vaccination is widespread vs. the U.K. where it's considered a normal childhood disease and vaccination is not recommended. There is a mounting body of evidence that the shingles epidemic is the unintended consequence of the chicken pox vaccine. When children got the chicken pox they exposed family and friends who already had chicken pox to a booster effect. So shingles was rarely seen even in the elderly if they had regular contact with children. Now shingles is being seen even in children which was unheard of before the vaccine.
But it's all a boon to big pharma: millions for the chicken pox vaccine and now a vaccine for shingles to deal with the unintended consequences of the chicken pox vaccine.