Once the health bars are displayed I cannot get them to disappear unless I exit to the main menu and re-enter the vault. I attempted to report this but through the email for the game in Google play, but was told to report it here in the forums.
I have a screenshot, but as I'm posting this on a mobile device I don't anticipate that I can post it here (if I'm able to post a photo on mobile, and someone can explain it to me, I will certainly do that).