SharePoint - AV scanning SharePoint.

Make sure you tell it to ignore your search indexes and other SharePoint areas!
See: https://support.microsoft.com/kb/952167

To be sure it is not hitting your index location, you can check where that is currently set by:

Central Admin -> Application Management -> Manage service applications
   -> Search Service Application ->Search Application Topology (Modify)
      -> IndexPartition/Query Component (Edit Properties).

Or via PowerShell, run the SharePoint 2010 Management Shell command:

   $(Get-SPEnterpriseSearchServiceInstance).CrawlComponents.Item(0).IndexLocation

 

PS:
https://support.microsoft.com/kb/322941 says
"Microsoft strongly encourages the development and adoption of SharePoint Portal Server VS API-based antivirus solutions."
but the only one I can find for SP2013 is ESET…https://www.eset.com/beta/sharepoint/

PPS: I have heard that Symantec have a SP2013 aware thing in beta. Supposedly a separate server. Will know more in a month or two.