My iPhone 5 seems to have a virus
An app called 'Health' appeared on my phone. I didn't install it. It's a white icon with a red heart in the upper right corner. It doesn't report to the Settings Menu, it doesn't report to the apps menu in Itunes. I can't remove it and ever since it mysteriously showed up the phone has become laggy with lot's of hangs, stuttering and other adverse behavior. Anybody know what this is and how to get rid of it?
iPhone 5s, iOS 8.1.2, Health App