Plus, our special report reaching the sky and risking it all. What you dont know about mount everest. We begin tonight with that troubling report on measles. The u. S. Is now in the grips of the worst outbreak in 18 years, and officials urge parents tonight to vaccinate their kids. 129 cases in just the first four months of the year. Thats according to the centers for Disease Control and prevention. By comparison there were 189 for all of 2013. California has the most cases with 58. New york is second with 24 and Washington State has 13. Dr. David newman from mt. Sinai Medical Center has the information you need to know. Well, the measles is actually a virus. The virus itself is fairly dangerous. It mostly has a proceed clift for children. Were in a significant outbreak of measles, and thats driven by a number of different factors. The most important factor is that there has been a steadily increasing number of people over the last 10 to 15 years who are not getting vaccinated. Parents