The plague temporarily introduced rabid animals to the plains and most likely would not have been added to bestiary lists. For example, rabid griffons never existed before or after plague but were mentioned in descriptions of the event.
The wolf hit you for that much because it was a diseased version of one of the native wolves to North Karana as opposed to a migrated Qeynos Hills wolf.
Player description of plague:
http://eqhorde.tripod.com/Eqhordepics/id4.html
This link has a post about the event and specifically mentions rabid wolves in the karanas
https://forums.daybreakgames.com/eq/...-bertox.60111/