Mac infected with virus

Uninstall Mackeeper using their uninstaller—it cause nothing but problems.

Finding false negatives is a way of upselling or getting you to buy this scamware.

If on the other hand you suspect you have installed adware/malware. Try running this trusted utility https://www.malwarebytes.com/mac/

Malware is actually fairly rare on the Mac platform and true viruses don't exist on the Mac platform, as Terence said. If you think you've picked something up MalwareBytes is a trustworthy program that can be used free of charge. I run it once a month on my computers at work - found one adware last year that it removed without a hitch.

You are being scammed. Uninstall MacKeeper.

It's not. None. There are no viruses in the wild that run on Macs. Is there a reason you think you may have contracted malware of some kind?