This statement is NOT factual, he does not want to charge him with assault, he and his office are simply looking into the matter. Please source if you have different information. I live in Dallas, 8 miles from the hospital and apartment. I hate seeing so much misinformation. Here's the link:
http://www.nytimes.com/2014/10/06/us/ebola.html
“We are actively having discussions as to whether or not we need to look into this as it relates to a criminal matter,” Dallas County’s district attorney, Craig Watkins, said on “Lone Star Politics” on NBC 5 on Sunday. “We’re working with all the different agencies to get to the bottom of it.” His spokeswoman said prosecutors had previously filed aggravated assault charges against people who were H.I.V. positive and knowingly had unprotected sex with others; and it was possible the same charge may apply in Mr. Duncan’s case.