Virus Resistance Nerf (#30256)

* Rebalance traits and nerf virus base resistance

* Fixes an oversight that can make sneezes spread blood spread diseases

code/datums/diseases/_MobProcs.dm

@@ -41,6 +41,10 @@ MARK: Helpers
 	if(spread_method == SPREAD_BLOOD)
 		return TRUE
 
+	// Check the disease can spread by a method other than SPREAD_BLOOD ones
+	if(!(D.spread_flags & (SPREAD_CONTACT_FEET | SPREAD_CONTACT_HANDS | SPREAD_CONTACT_GENERAL | SPREAD_AIRBORNE)))
+		return FALSE
+
 	if(src.mind && HAS_TRAIT(src.mind, TRAIT_GERMOPHOBE) && prob(85))
 		return FALSE
 

code/datums/diseases/advance/symptoms/viral.dm

@@ -16,8 +16,8 @@ BONUS
 /datum/symptom/viraladaptation
 	name = "Viral self-adaptation"
 	stealth = 3
-	resistance = 5
-	stage_speed = -3
+	resistance = 3
+	stage_speed = -2
 	level = 3
 
 /datum/symptom/viraladaptation/symptom_act(datum/disease/advance/A, unmitigated)

code/datums/diseases/advance/symptoms/youth.dm

@@ -19,7 +19,7 @@ BONUS
 
 	name = "Eternal Youth"
 	stealth = 3
-	resistance = 4
+	resistance = 2
 	stage_speed = 4
 	transmissibility = -4
 	level = 5