The rotavirus vaccine is more important than it may seem. At first glance, diarrhea seems like a rather minor problem. Although every child will likely get rotavirus in the first two years of life, most are able to weather it easily at home. However, over fifty thousand children a year are hospitalized because of the disease. In addition, the vaccine is simple, is orally administered so it doesn’t hurt, and has minimal side effects. Given this combination, we put the rotavirus vaccine on our second tier of recommendations. It is not as important as HiB, pneumococcus, or pertussis, which can have permanent effects, but it is important.