Fixes non-advanced diseases vaccines.

code/datums/diseases/_disease.dm

@@ -103,8 +103,9 @@
 /datum/disease/proc/cure(add_resistance = TRUE)
 	if(affected_mob)
 		if(disease_flags & CAN_RESIST)
-			if(add_resistance && !(type in affected_mob.resistances))
-				affected_mob.resistances += type
+			var/id = GetDiseaseID()
+			if(add_resistance && !(id in affected_mob.resistances))
+				affected_mob.resistances += id
 		remove_virus()
 	qdel(src)
 
@@ -121,7 +122,7 @@
 
 
 /datum/disease/proc/GetDiseaseID()
-	return type
+	return "[type]"
 
 //don't use this proc directly. this should only ever be called by cure()
 /datum/disease/proc/remove_virus()

code/datums/diseases/advance/advance.dm

@@ -95,15 +95,6 @@
 		return 0
 	return 1
 
-// To add special resistances.
-/datum/disease/advance/cure(resistance=1)
-	if(affected_mob)
-		var/id = "[GetDiseaseID()]"
-		if(resistance && !(id in affected_mob.resistances))
-			affected_mob.resistances[id] = id
-		remove_virus()
-	qdel(src)	//delete the datum to stop it processing
-
 // Returns the advance disease with a different reference memory.
 /datum/disease/advance/Copy(process = 0)
 	return new /datum/disease/advance(process, src, 1)