New CDC document reveals how new information about delta variant transmissibility CDC report says delta variant is as contagious as chickenpox A CDC document revealed new information about the delta variant, including its impact on vaccinated people. FOX 26's Maria Salazar heard from an infectious disease expert about what to make of the new information, and the comparison between the contagiousness of chickenpox and the delta variant. HOUSTON - An internal document by the the Centers for Disease Control and Prevention reveals new information about the delta variant including how it is impacting those who are vaccinated. It was first published by the Washington Post.