Apple has finally decided to crack down on antivirus apps, and removing them from the App Store. Although there has been no official statement from Apple on a policy change, Apple’s loose guidelines allow them to pull pretty much anything at any time, particularly something like antivirus which has questionable utility within the iPad and iPhone's ios system.
Searching 'Antivirus' still returns many results. However, after being inspected, all of the related apps they checked were not actually anti-virus products. Instead they were either games or apps replicating ‘Find My iPhone’.