[MIRROR] Disease antagonist (#5815)

* Disease antagonist

* Update mobs.dm

* can I go to sleep yet

code/modules/mob/mob_helpers.dm

@@ -363,8 +363,10 @@ It's fairly easy to fix if dealing with single letters but not so much with comp
 				if(M.mind in SSticker.mode.apprentices)
 					return 2
 			if("monkey")
-				if(M.viruses && (locate(/datum/disease/transformation/jungle_fever) in M.viruses))
-					return 2
+				if(isliving(M))
+					var/mob/living/L = M
+					if(L.diseases && (locate(/datum/disease/transformation/jungle_fever) in L.diseases))
+						return 2
 		return TRUE
 	if(M.mind && LAZYLEN(M.mind.antag_datums)) //they have an antag datum!
 		return TRUE