. >>> big names speaking out, including actress amanda peet.biggest motivation. it is her three children and newborn son. >> part of the reason i'm here is because my son is only 9 weeks old so he can't have the mmr vaccine until he's 12 months old. so he's one of the vulnerable infants and if he contracted measles somehow, somewhere i think most people know that there is a 90% chance that the disease will be transmitted. it's one of the most contagious microbes out there. if my son were to get it he would be really -- he'd be in trouble and so it's important to remember it's not just about your child or your school-aged child. it's about -- it's about transmission and the rate of transmission and how these things could catch like wildfire and create a real outbreak. >> have you been acting differently now with your son in terms of where you will take him in public? he's only 9 weeks old because of this outbreak? >> you know i have to say it has crossed my mind when i think about taking him on the school run or not taking him on the school run

actress amanda peet speaking out passionately why she believes every parent should vaccinate their childrennt income. so i can focus on what matters most. [ female announcer ] everyone has a moment when tomorrow becomes real. transamerica. le ® speak with your eyecare professional to... ...upgrade your lenses to transitions ® signature ™ . . >>> the children at the heart of the measles outbreak in illinois are the tiniest babies too young to be vaccinated now diagnosed with a highly contagious measles diseases. as of today it has spread to 16 states in the district of columbia. health officials thought the disease was eliminated over the u.s. 15 years ago. the debate over this is red hot and actress amanda pete talking about her personal decision to make that key decision when her first child was born. i speak movement and a lot of my friends weren't vaccinating and were bewildered as to why i was considering vaccinating and my brother-in-law is an infectious diseases pediatric doctor in philadelphia and he suggested that i try to get out there and help to disseminate information about the