McCarthy's book dealing with autism, "Louder than Words: A Mother's Journey in Healing Autism", was published September 17, 2007. She stated both in her book and during her appearance on "The Oprah Winfrey Show" that her husband was unable to deal with their son's autism, which led to their divorce. In 2008, she appeared on a "Larry King Live" special dedicated to the subject and argued that vaccines can trigger autism. As of 2008, her son's physician was vaccine critic Jay Gordon. In an April 27, 2010 PBS "Frontline" documentary, she was interviewed about the debate between vaccine opponents and public health experts.