Sounds like a really great excuse to keep my sister-in-law from visiting. Of course we live in Eastern King County, WA where this this virus has been passing around the community since sometime in December. Our friends do not wonder if they are going to get it... they wonder if what they had earlier this year that didn't even keep them home was the virus and in many cases it probably was. We will never know if they were infected because there are not enough tests to go around here for all the celebrities and politicians who want them. Even if there was and they do not tell if you had it, only if you currently have it.
You need to tell your relative that you afraid of getting this flu type virus because you are convinced that it could kill you and you are self isolating. There is no way that they haven't seen all the hype. They still might make fun of you for the next few years or until something else kills you. Even then it will provide a topic of discussion at your funeral.