And another quote from the article "Gamarue.I, a worm identified by Microsoft in 2012" which has documentation at Microsoft.com[1] and at some random site [2] saying "This threat tries to use the Windows Autorun function to spread via removable drives, such as USB flash drives." and "Worm:Win32/Gamarue.I copies four essential components from one location to another. These four components are the four files used in the attack: "desktop.ini," "~$wb.usbdrv," "usb drive (1gb).lnk" and "thumbs.db.""

Self-propagating it is, self-propagating over a network it doesn't seem to be. Is it more likely "A School in Bradford plugged an infected USB stick into laptops while setting them up, and disabling built-in antivirus in favour of some third-party less effective antivirus"?

[1] https://www.microsoft.com/en-us/wdsi/threats/malware-encyclo...

[2] https://www.enigmasoftware.com/wormwin32gamaruei-removal/