You don't have a virus. Only way you'll run into problems like that is if you jailbreak, and even then I'm not sure a true virus is possible on an iPad. Its possible you can run into malware if you jailbreak and download from Cydia.
First thing to try is always to reboot the device. (This works on PC, Mac, iPad, iPod, iPhone, etc.) Cures more problems than any other troubleshooting tip.
After that, try f4780y's instructions. Worst comes to worst, full restore should do the trick. Doesn't take that long either.