Why do people not vaccinate their kids? My child has been vaccinated but only had his first lot as is 20 months. He has contracted measles. I chose to vaccinate him against this. Ill advised people that think if they dont vaccinate there's only a slim chance your child will get this disease you're wrong. You're increasing everyone's chance of contracting the illness by ruining the herd immunity that this country had created. Not only are you doing this, you're increasing people with compromised immune systems' chance of death. I feel terrible that my child has to go through this because of others lack of understanding.