This is more just about warning people not to do it, don't use disinfectant in the way Trump suggested it or questioned it, Australia's top doctor even said not to do it, after Trump's comments, I think every nation had a duty of care after those comments to tell people not to do it. It's just a duty of care if you know someone suggested something dangerous in front of your kids, you would tell them don't do it, because there are some people that don't know better or would follow Trump's comments, like
@Justadude said about the 100+ people in Maryland ringing up the emergency hotline about disinfectant.
At least Trump backed down and said it was a very sarcastic question, whether he was telling the truth or not. It was better than saying nothing after the original suggestion or question, or suggestion in a form of a question.