These database files can be installed either by double-clicking in the Finder, or via the XAV command line tool:
/Applications/ClamXAV.app/Contents/MacOS/XAV --update --file /full/path/to/database_file.xavz
These database files can be installed either by double-clicking in the Finder, or via the XAV command line tool:
/Applications/ClamXAV.app/Contents/MacOS/XAV --update --file /full/path/to/database_file.xavz