It is misleading. The slashdot summary is setup to imply that parents are preventing their kids from getting the vaccine b/c the parents are stupid.
In only a small fraction of the total cases is the reason for getting the disease b/c the parents declined to have their kids vaccinated. From the actual article: "Of those who were completely unvaccinated, 86% were because the parents declined vaccination." However, the vast majority of cases were for kids who were too young to be fully vaccinated.
Sure, vaccinating everyone against it would eliminate the risk, but to date this vaccine is not often recommended for the general adult population.