diff --git a/code/__DEFINES/diseases.dm b/code/__DEFINES/diseases.dm
new file mode 100644
index 00000000000..58d8066e9cf
--- /dev/null
+++ b/code/__DEFINES/diseases.dm
@@ -0,0 +1,26 @@
+//Visibility Flags
+#define HIDDEN_SCANNER	1
+#define HIDDEN_PANDEMIC	2
+
+//Disease Flags
+#define CURABLE		1
+#define CAN_CARRY	2
+#define CAN_RESIST	4
+
+//Spread Flags
+#define VIRUS_SPREAD_SPECIAL 1
+#define VIRUS_SPREAD_NON_CONTAGIOUS 2
+#define VIRUS_SPREAD_BLOOD 4
+#define VIRUS_SPREAD_CONTACT_FLUIDS 8
+#define VIRUS_SPREAD_CONTACT_SKIN 16
+#define VIRUS_SPREAD_AIRBORNE 32
+
+
+//Severity Defines
+#define VIRUS_SEVERITY_POSITIVE		"Positive"  //Diseases that buff, heal, or at least do nothing at all
+#define VIRUS_SEVERITY_NONTHREAT	"Harmless"  //Diseases that may have annoying effects, but nothing disruptive (sneezing)
+#define VIRUS_SEVERITY_MINOR		"Minor"	    //Diseases that can annoy in concrete ways (dizziness)
+#define VIRUS_SEVERITY_MEDIUM		"Medium"    //Diseases that can do minor harm, or severe annoyance (vomit)
+#define VIRUS_SEVERITY_HARMFUL		"Harmful"   //Diseases that can do significant harm, or severe disruption (brainrot)
+#define VIRUS_SEVERITY_DANGEROUS 	"Dangerous" //Diseases that can kill or maim if left untreated (flesh eating, blindness)
+#define VIRUS_SEVERITY_BIOHAZARD	"BIOHAZARD" //Diseases that can quickly kill an unprepared victim (fungal tb, gbs)
diff --git a/code/datums/components/infective.dm b/code/datums/components/infective.dm
new file mode 100644
index 00000000000..cedede6b04f
--- /dev/null
+++ b/code/datums/components/infective.dm
@@ -0,0 +1,13 @@
+/datum/component/infective
+	var/list/datum/disease/diseases //make sure these are the static, non-processing versions!
+
+/datum/component/infective/Initialize(list/datum/disease/_diseases)
+	RegisterSignal(COMSIG_MOVABLE_CROSSED, .proc/Infect)
+	diseases = _diseases
+
+/datum/component/infective/proc/Infect(atom/movable/AM)
+	var/mob/living/carbon/victim = AM
+	if(istype(victim))
+		for(var/datum/disease/D in diseases)
+			victim.ContactContractDisease(D, "feet")
+		return TRUE
\ No newline at end of file
diff --git a/code/datums/diseases/_MobProcs.dm b/code/datums/diseases/_MobProcs.dm
index a00d43ad8fd..f13239a113b 100644
--- a/code/datums/diseases/_MobProcs.dm
+++ b/code/datums/diseases/_MobProcs.dm
@@ -23,7 +23,7 @@
 	return 1
 
 
-/mob/proc/ContractDisease(datum/disease/D)
+/mob/proc/ContactContractDisease(datum/disease/D)
 	if(!CanContractDisease(D))
 		return 0
 	AddDisease(D)
@@ -56,42 +56,31 @@
 		DD.affected_mob.med_hud_set_status()
 
 
-/mob/living/carbon/ContractDisease(datum/disease/D)
+/mob/living/carbon/ContactContractDisease(datum/disease/D, target_zone)
 	if(!CanContractDisease(D))
 		return 0
 
 	var/obj/item/clothing/Cl = null
-	var/passed = 1
+	var/passed = TRUE
 
-	var/head_ch = 100
+	var/head_ch = 80
 	var/body_ch = 100
-	var/hands_ch = 25
-	var/feet_ch = 25
-
-	if(D.spread_flags & CONTACT_HANDS)
-		head_ch = 0
-		body_ch = 0
-		hands_ch = 100
-		feet_ch = 0
-	if(D.spread_flags & CONTACT_FEET)
-		head_ch = 0
-		body_ch = 0
-		hands_ch = 0
-		feet_ch = 100
+	var/hands_ch = 35
+	var/feet_ch = 15
 
 	if(prob(15/D.permeability_mod))
 		return
 
 	if(satiety>0 && prob(satiety/10)) // positive satiety makes it harder to contract the disease.
 		return
-
-	var/target_zone = pick(head_ch;1,body_ch;2,hands_ch;3,feet_ch;4)
+	if(!target_zone)
+		target_zone = pick(head_ch;"head",body_ch;"body",hands_ch;"hands",feet_ch;"feet")
 
 	if(ishuman(src))
 		var/mob/living/carbon/human/H = src
 
 		switch(target_zone)
-			if(1)
+			if("head")
 				if(isobj(H.head) && !istype(H.head, /obj/item/paper))
 					Cl = H.head
 					passed = prob((Cl.permeability_coefficient*100) - 1)
@@ -101,14 +90,14 @@
 				if(passed && isobj(H.wear_neck))
 					Cl = H.wear_neck
 					passed = prob((Cl.permeability_coefficient*100) - 1)
-			if(2)
+			if("body")
 				if(isobj(H.wear_suit))
 					Cl = H.wear_suit
 					passed = prob((Cl.permeability_coefficient*100) - 1)
 				if(passed && isobj(slot_w_uniform))
 					Cl = slot_w_uniform
 					passed = prob((Cl.permeability_coefficient*100) - 1)
-			if(3)
+			if("hands")
 				if(isobj(H.wear_suit) && H.wear_suit.body_parts_covered&HANDS)
 					Cl = H.wear_suit
 					passed = prob((Cl.permeability_coefficient*100) - 1)
@@ -116,7 +105,7 @@
 				if(passed && isobj(H.gloves))
 					Cl = H.gloves
 					passed = prob((Cl.permeability_coefficient*100) - 1)
-			if(4)
+			if("feet")
 				if(isobj(H.wear_suit) && H.wear_suit.body_parts_covered&FEET)
 					Cl = H.wear_suit
 					passed = prob((Cl.permeability_coefficient*100) - 1)
@@ -128,19 +117,30 @@
 	else if(ismonkey(src))
 		var/mob/living/carbon/monkey/M = src
 		switch(target_zone)
-			if(1)
+			if("head")
 				if(M.wear_mask && isobj(M.wear_mask))
 					Cl = M.wear_mask
 					passed = prob((Cl.permeability_coefficient*100) - 1)
 
-	if(!passed && (D.spread_flags & AIRBORNE) && !internal)
-		passed = (prob((50*D.permeability_mod) - 1))
-
 	if(passed)
 		AddDisease(D)
 
+/mob/proc/AirborneContractDisease(datum/disease/D)
+	if((D.spread_flags & VIRUS_SPREAD_AIRBORNE) && prob((50*D.permeability_mod) - 1))
+		ForceContractDisease(D)
 
-//Same as ContractDisease, except never overidden clothes checks
+/mob/living/carbon/AirborneContractDisease(datum/disease/D)
+	if(internal)
+		return
+	..()
+
+/mob/living/carbon/human/AirborneContractDisease(datum/disease/D)
+	if(dna && (NOBREATH in dna.species.species_traits))
+		return
+	..()
+
+
+//Proc to use when you 100% want to infect someone, as long as they aren't immune
 /mob/proc/ForceContractDisease(datum/disease/D)
 	if(!CanContractDisease(D))
 		return 0
diff --git a/code/datums/diseases/_disease.dm b/code/datums/diseases/_disease.dm
index 13ad3ece4e6..80dc585eb31 100644
--- a/code/datums/diseases/_disease.dm
+++ b/code/datums/diseases/_disease.dm
@@ -1,36 +1,8 @@
-
-//Visibility Flags
-#define HIDDEN_SCANNER	1
-#define HIDDEN_PANDEMIC	2
-
-//Disease Flags
-#define CURABLE		1
-#define CAN_CARRY	2
-#define CAN_RESIST	4
-
-//Spread Flags
-#define SPECIAL 1
-#define NON_CONTAGIOUS 2
-#define BLOOD 4
-#define CONTACT_FEET 8
-#define CONTACT_HANDS 16
-#define CONTACT_GENERAL 32
-#define AIRBORNE 64
-
-
-//Severity Defines
-#define NONTHREAT	"No threat"
-#define MINOR		"Minor"
-#define MEDIUM		"Medium"
-#define HARMFUL		"Harmful"
-#define DANGEROUS 	"Dangerous!"
-#define BIOHAZARD	"BIOHAZARD THREAT!"
-
 /datum/disease
 	//Flags
 	var/visibility_flags = 0
 	var/disease_flags = CURABLE|CAN_CARRY|CAN_RESIST
-	var/spread_flags = AIRBORNE
+	var/spread_flags = VIRUS_SPREAD_AIRBORNE | VIRUS_SPREAD_CONTACT_FLUIDS | VIRUS_SPREAD_CONTACT_SKIN
 
 	//Fluff
 	var/form = "Virus"
@@ -54,7 +26,7 @@
 	var/carrier = FALSE //If our host is only a carrier
 	var/bypasses_immunity = FALSE //Does it skip species virus immunity check? Some things may diseases and not viruses
 	var/permeability_mod = 1
-	var/severity =	NONTHREAT
+	var/severity = VIRUS_SEVERITY_POSITIVE
 	var/list/required_organs = list()
 	var/needs_all_cures = TRUE
 	var/list/strain_data = list() //dna_spread special bullshit
@@ -95,25 +67,22 @@
 	if(!. || (needs_all_cures && . < cures.len))
 		return 0
 
-
+//Airborne spreading
 /datum/disease/proc/spread(force_spread = 0)
 	if(!affected_mob)
 		return
 
-	if((spread_flags & SPECIAL || spread_flags & NON_CONTAGIOUS || spread_flags & BLOOD) && !force_spread)
+	if(!(spread_flags & VIRUS_SPREAD_AIRBORNE) && !force_spread)
 		return
 
 	if(affected_mob.reagents.has_reagent("spaceacillin") || (affected_mob.satiety > 0 && prob(affected_mob.satiety/10)))
 		return
 
-	var/spread_range = 1
+	var/spread_range = 2
 
 	if(force_spread)
 		spread_range = force_spread
 
-	if(spread_flags & AIRBORNE)
-		spread_range++
-
 	var/turf/T = affected_mob.loc
 	if(istype(T))
 		for(var/mob/living/carbon/C in oview(spread_range, affected_mob))
@@ -121,7 +90,7 @@
 			if(V)
 				while(TRUE)
 					if(V == T)
-						C.ContractDisease(src)
+						C.AirborneContractDisease(src)
 						break
 					var/turf/Temp = get_step_towards(V, T)
 					if(!CANATMOSPASS(V, Temp))
@@ -152,12 +121,6 @@
 /datum/disease/proc/GetDiseaseID()
 	return type
 
-
-/datum/disease/proc/IsSpreadByTouch()
-	if(spread_flags & CONTACT_FEET || spread_flags & CONTACT_HANDS || spread_flags & CONTACT_GENERAL)
-		return 1
-	return 0
-
 //don't use this proc directly. this should only ever be called by cure()
 /datum/disease/proc/remove_virus()
 	affected_mob.viruses -= src		//remove the datum from the list
diff --git a/code/datums/diseases/advance/advance.dm b/code/datums/diseases/advance/advance.dm
index 062f5cddee6..1070039f0c4 100644
--- a/code/datums/diseases/advance/advance.dm
+++ b/code/datums/diseases/advance/advance.dm
@@ -183,19 +183,19 @@
 		properties["stealth"] += S.stealth
 		properties["stage_rate"] += S.stage_speed
 		properties["transmittable"] += S.transmittable
-		properties["severity"] = max(properties["severity"], S.severity) // severity is based on the highest severity symptom
+		if(!S.neutered)
+			properties["severity"] = max(properties["severity"], S.severity) // severity is based on the highest severity non-neutered symptom
 	return
 
 // Assign the properties that are in the list.
 /datum/disease/advance/proc/AssignProperties()
 
 	if(properties && properties.len)
-		switch(properties["stealth"])
-			if(2 to INFINITY)
-				visibility_flags = HIDDEN_SCANNER
+		if(properties["stealth"] >= 2)
+			visibility_flags = HIDDEN_SCANNER
+
+		SetSpread(Clamp(2 ** (properties["transmittable"] - symptoms.len), VIRUS_SPREAD_BLOOD, VIRUS_SPREAD_AIRBORNE))
 
-		// The more symptoms we have, the less transmittable it is but some symptoms can make up for it.
-		SetSpread(Clamp(2 ** (properties["transmittable"] - symptoms.len), BLOOD, AIRBORNE))
 		permeability_mod = max(Ceiling(0.4 * properties["transmittable"]), 1)
 		cure_chance = 15 - Clamp(properties["resistance"], -5, 5) // can be between 10 and 20
 		stage_prob = max(properties["stage_rate"], 2)
@@ -208,35 +208,43 @@
 // Assign the spread type and give it the correct description.
 /datum/disease/advance/proc/SetSpread(spread_id)
 	switch(spread_id)
-		if(NON_CONTAGIOUS)
+		if(VIRUS_SPREAD_NON_CONTAGIOUS)
+			spread_flags = VIRUS_SPREAD_NON_CONTAGIOUS
 			spread_text = "None"
-		if(SPECIAL)
+		if(VIRUS_SPREAD_SPECIAL)
+			spread_flags = VIRUS_SPREAD_SPECIAL
 			spread_text = "None"
-		if(CONTACT_GENERAL, CONTACT_HANDS, CONTACT_FEET)
-			spread_text = "On contact"
-		if(AIRBORNE)
-			spread_text = "Airborne"
-		if(BLOOD)
+		if(VIRUS_SPREAD_BLOOD)
+			spread_flags = VIRUS_SPREAD_BLOOD
 			spread_text = "Blood"
-
-	spread_flags = spread_id
+		if(VIRUS_SPREAD_CONTACT_FLUIDS)
+			spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_FLUIDS
+			spread_text = "Fluids"
+		if(VIRUS_SPREAD_CONTACT_SKIN)
+			spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_FLUIDS | VIRUS_SPREAD_CONTACT_SKIN
+			spread_text = "On contact"
+		if(VIRUS_SPREAD_AIRBORNE)
+			spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_FLUIDS | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_AIRBORNE
+			spread_text = "Airborne"
 
 /datum/disease/advance/proc/SetSeverity(level_sev)
 
 	switch(level_sev)
 
 		if(-INFINITY to 0)
-			severity = NONTHREAT
+			severity = VIRUS_SEVERITY_POSITIVE
 		if(1)
-			severity = MINOR
+			severity = VIRUS_SEVERITY_NONTHREAT
 		if(2)
-			severity = MEDIUM
+			severity = VIRUS_SEVERITY_MINOR
 		if(3)
-			severity = HARMFUL
+			severity = VIRUS_SEVERITY_MEDIUM
 		if(4)
-			severity = DANGEROUS
-		if(5 to INFINITY)
-			severity = BIOHAZARD
+			severity = VIRUS_SEVERITY_HARMFUL
+		if(5)
+			severity = VIRUS_SEVERITY_DANGEROUS
+		if(6 to INFINITY)
+			severity = VIRUS_SEVERITY_BIOHAZARD
 		else
 			severity = "Unknown"
 
diff --git a/code/datums/diseases/advance/symptoms/choking.dm b/code/datums/diseases/advance/symptoms/choking.dm
index 4829920d4fa..4b12ec403c9 100644
--- a/code/datums/diseases/advance/symptoms/choking.dm
+++ b/code/datums/diseases/advance/symptoms/choking.dm
@@ -94,7 +94,7 @@ Bonus
 	stage_speed = -1
 	transmittable = -2
 	level = 7
-	severity = 3
+	severity = 6
 	base_message_chance = 15
 	symptom_delay_min = 14
 	symptom_delay_max = 30
diff --git a/code/datums/diseases/advance/symptoms/cough.dm b/code/datums/diseases/advance/symptoms/cough.dm
index d3c3ea2da89..323f794eeea 100644
--- a/code/datums/diseases/advance/symptoms/cough.dm
+++ b/code/datums/diseases/advance/symptoms/cough.dm
@@ -40,7 +40,7 @@ BONUS
 		return
 	if(A.properties["stealth"] >= 4)
 		suppress_warning = TRUE
-	if(A.spread_flags &= AIRBORNE) //infect bystanders
+	if(A.spread_flags &= VIRUS_SPREAD_AIRBORNE) //infect bystanders
 		infective = TRUE
 	if(A.properties["resistance"] >= 3) //strong enough to drop items
 		power = 1.5
diff --git a/code/datums/diseases/advance/symptoms/deafness.dm b/code/datums/diseases/advance/symptoms/deafness.dm
index 3bae01c7a72..c2afb34a9eb 100644
--- a/code/datums/diseases/advance/symptoms/deafness.dm
+++ b/code/datums/diseases/advance/symptoms/deafness.dm
@@ -24,7 +24,7 @@ Bonus
 	stage_speed = -1
 	transmittable = -3
 	level = 4
-	severity = 3
+	severity = 4
 	base_message_chance = 100
 	symptom_delay_min = 25
 	symptom_delay_max = 80
diff --git a/code/datums/diseases/advance/symptoms/genetics.dm b/code/datums/diseases/advance/symptoms/genetics.dm
index 836b4a47192..af1e4600246 100644
--- a/code/datums/diseases/advance/symptoms/genetics.dm
+++ b/code/datums/diseases/advance/symptoms/genetics.dm
@@ -23,7 +23,7 @@ Bonus
 	stage_speed = 0
 	transmittable = -3
 	level = 6
-	severity = 3
+	severity = 4
 	var/list/possible_mutations
 	var/archived_dna = null
 	base_message_chance = 50
diff --git a/code/datums/diseases/advance/symptoms/hallucigen.dm b/code/datums/diseases/advance/symptoms/hallucigen.dm
index 76b92159d88..5509f8b07bb 100644
--- a/code/datums/diseases/advance/symptoms/hallucigen.dm
+++ b/code/datums/diseases/advance/symptoms/hallucigen.dm
@@ -23,7 +23,7 @@ Bonus
 	stage_speed = -3
 	transmittable = -1
 	level = 5
-	severity = 3
+	severity = 2
 	base_message_chance = 25
 	symptom_delay_min = 25
 	symptom_delay_max = 90
diff --git a/code/datums/diseases/advance/symptoms/narcolepsy.dm b/code/datums/diseases/advance/symptoms/narcolepsy.dm
index cc13d994064..24ba024aa6f 100644
--- a/code/datums/diseases/advance/symptoms/narcolepsy.dm
+++ b/code/datums/diseases/advance/symptoms/narcolepsy.dm
@@ -22,7 +22,7 @@ Bonus
 	level = 6
 	symptom_delay_min = 15
 	symptom_delay_max = 80
-	severity = 5
+	severity = 4
 	var/sleep_level = 0
 	var/sleepy_ticks = 0
 	var/stamina = FALSE
diff --git a/code/datums/diseases/advance/symptoms/sensory.dm b/code/datums/diseases/advance/symptoms/sensory.dm
index b9c22954e7f..6a987d5531d 100644
--- a/code/datums/diseases/advance/symptoms/sensory.dm
+++ b/code/datums/diseases/advance/symptoms/sensory.dm
@@ -23,7 +23,6 @@ Bonus
 	stage_speed = -4
 	transmittable = -3
 	level = 5
-	severity = 0
 	symptom_delay_min = 5
 	symptom_delay_max = 10
 	var/purge_alcohol = FALSE
diff --git a/code/datums/diseases/advance/symptoms/vision.dm b/code/datums/diseases/advance/symptoms/vision.dm
index 2f290910719..84f9ef49cca 100644
--- a/code/datums/diseases/advance/symptoms/vision.dm
+++ b/code/datums/diseases/advance/symptoms/vision.dm
@@ -24,7 +24,7 @@ Bonus
 	stage_speed = -4
 	transmittable = -3
 	level = 5
-	severity = 4
+	severity = 5
 	base_message_chance = 50
 	symptom_delay_min = 25
 	symptom_delay_max = 80
diff --git a/code/datums/diseases/advance/symptoms/vomit.dm b/code/datums/diseases/advance/symptoms/vomit.dm
index e271bce5ed0..14d7f105ab0 100644
--- a/code/datums/diseases/advance/symptoms/vomit.dm
+++ b/code/datums/diseases/advance/symptoms/vomit.dm
@@ -28,7 +28,7 @@ Bonus
 	stage_speed = 0
 	transmittable = 1
 	level = 3
-	severity = 4
+	severity = 3
 	base_message_chance = 100
 	symptom_delay_min = 25
 	symptom_delay_max = 80
diff --git a/code/datums/diseases/advance/symptoms/weight.dm b/code/datums/diseases/advance/symptoms/weight.dm
index bfd10ee7fe5..37fa0f5fa59 100644
--- a/code/datums/diseases/advance/symptoms/weight.dm
+++ b/code/datums/diseases/advance/symptoms/weight.dm
@@ -24,7 +24,7 @@ Bonus
 	stage_speed = -2
 	transmittable = -2
 	level = 4
-	severity = 1
+	severity = 3
 	base_message_chance = 100
 	symptom_delay_min = 15
 	symptom_delay_max = 45
@@ -75,7 +75,7 @@ Bonus
 	stage_speed = -2
 	transmittable = -2
 	level = 3
-	severity = 1
+	severity = 3
 	base_message_chance = 100
 	symptom_delay_min = 15
 	symptom_delay_max = 45
diff --git a/code/datums/diseases/anxiety.dm b/code/datums/diseases/anxiety.dm
index 780cb0b1e55..4673d2e9807 100644
--- a/code/datums/diseases/anxiety.dm
+++ b/code/datums/diseases/anxiety.dm
@@ -3,13 +3,13 @@
 	form = "Infection"
 	max_stages = 4
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Ethanol"
 	cures = list("ethanol")
 	agent = "Excess Lepidopticides"
 	viable_mobtypes = list(/mob/living/carbon/human, /mob/living/carbon/monkey)
 	desc = "If left untreated subject will regurgitate butterflies."
-	severity = MEDIUM
+	severity = VIRUS_SEVERITY_MINOR
 
 /datum/disease/anxiety/stage_act()
 	..()
diff --git a/code/datums/diseases/appendicitis.dm b/code/datums/diseases/appendicitis.dm
index 8c681b8ec3e..61d1519e7dc 100644
--- a/code/datums/diseases/appendicitis.dm
+++ b/code/datums/diseases/appendicitis.dm
@@ -7,9 +7,9 @@
 	viable_mobtypes = list(/mob/living/carbon/human)
 	permeability_mod = 1
 	desc = "If left untreated the subject will become very weak, and may vomit often."
-	severity = "Dangerous!"
+	severity = VIRUS_SEVERITY_MEDIUM
 	disease_flags = CAN_CARRY|CAN_RESIST
-	spread_flags = NON_CONTAGIOUS
+	spread_flags = VIRUS_SPREAD_NON_CONTAGIOUS
 	visibility_flags = HIDDEN_PANDEMIC
 	required_organs = list(/obj/item/organ/appendix)
 	bypasses_immunity = TRUE // Immunity is based on not having an appendix; this isn't a virus
diff --git a/code/datums/diseases/beesease.dm b/code/datums/diseases/beesease.dm
index 6ff38ce0fd1..a1373d95a1f 100644
--- a/code/datums/diseases/beesease.dm
+++ b/code/datums/diseases/beesease.dm
@@ -3,13 +3,13 @@
 	form = "Infection"
 	max_stages = 4
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Sugar"
 	cures = list("sugar")
 	agent = "Apidae Infection"
 	viable_mobtypes = list(/mob/living/carbon/human, /mob/living/carbon/monkey)
 	desc = "If left untreated subject will regurgitate bees."
-	severity = DANGEROUS
+	severity = VIRUS_SEVERITY_MEDIUM
 
 /datum/disease/beesease/stage_act()
 	..()
diff --git a/code/datums/diseases/brainrot.dm b/code/datums/diseases/brainrot.dm
index a4b6d52bc89..576518b9554 100644
--- a/code/datums/diseases/brainrot.dm
+++ b/code/datums/diseases/brainrot.dm
@@ -2,7 +2,7 @@
 	name = "Brainrot"
 	max_stages = 4
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Mannitol"
 	cures = list("mannitol")
 	agent = "Cryptococcus Cosmosis"
@@ -10,7 +10,7 @@
 	cure_chance = 15//higher chance to cure, since two reagents are required
 	desc = "This disease destroys the braincells, causing brain fever, brain necrosis and general intoxication."
 	required_organs = list(/obj/item/organ/brain)
-	severity = DANGEROUS
+	severity = VIRUS_SEVERITY_HARMFUL
 
 /datum/disease/brainrot/stage_act() //Removed toxloss because damaging diseases are pretty horrible. Last round it killed the entire station because the cure didn't work -- Urist -ACTUALLY Removed rather than commented out, I don't see it returning - RR
 	..()
diff --git a/code/datums/diseases/cold.dm b/code/datums/diseases/cold.dm
index 2c3aac06bdb..7962ce220d4 100644
--- a/code/datums/diseases/cold.dm
+++ b/code/datums/diseases/cold.dm
@@ -1,14 +1,13 @@
 /datum/disease/cold
 	name = "The Cold"
 	max_stages = 3
-	spread_flags = AIRBORNE
 	cure_text = "Rest & Spaceacillin"
 	cures = list("spaceacillin")
 	agent = "XY-rhinovirus"
 	viable_mobtypes = list(/mob/living/carbon/human, /mob/living/carbon/monkey)
 	permeability_mod = 0.5
 	desc = "If left untreated the subject will contract the flu."
-	severity = MINOR
+	severity = VIRUS_SEVERITY_NONTHREAT
 
 /datum/disease/cold/stage_act()
 	..()
@@ -62,5 +61,5 @@
 			if(prob(1) && prob(50))
 				if(!affected_mob.resistances.Find(/datum/disease/flu))
 					var/datum/disease/Flu = new /datum/disease/flu(0)
-					affected_mob.ContractDisease(Flu)
+					affected_mob.ForceContractDisease(Flu)
 					cure()
\ No newline at end of file
diff --git a/code/datums/diseases/cold9.dm b/code/datums/diseases/cold9.dm
index e64875332b6..6a21dbfd54d 100644
--- a/code/datums/diseases/cold9.dm
+++ b/code/datums/diseases/cold9.dm
@@ -2,13 +2,13 @@
 	name = "The Cold"
 	max_stages = 3
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Common Cold Anti-bodies & Spaceacillin"
 	cures = list("spaceacillin")
 	agent = "ICE9-rhinovirus"
 	viable_mobtypes = list(/mob/living/carbon/human)
 	desc = "If left untreated the subject will slow, as if partly frozen."
-	severity = MEDIUM
+	severity = VIRUS_SEVERITY_HARMFUL
 
 /datum/disease/cold9/stage_act()
 	..()
diff --git a/code/datums/diseases/dna_spread.dm b/code/datums/diseases/dna_spread.dm
index c96a22d472a..fefdabd9c8c 100644
--- a/code/datums/diseases/dna_spread.dm
+++ b/code/datums/diseases/dna_spread.dm
@@ -2,7 +2,7 @@
 	name = "Space Retrovirus"
 	max_stages = 4
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Mutadone"
 	cures = list("mutadone")
 	disease_flags = CAN_CARRY|CAN_RESIST|CURABLE
@@ -11,7 +11,7 @@
 	var/datum/dna/original_dna = null
 	var/transformed = 0
 	desc = "This disease transplants the genetic code of the initial vector into new hosts."
-	severity = MEDIUM
+	severity = VIRUS_SEVERITY_MEDIUM
 
 
 /datum/disease/dnaspread/stage_act()
diff --git a/code/datums/diseases/fake_gbs.dm b/code/datums/diseases/fake_gbs.dm
index 1571c8719b7..e62a8b491d2 100644
--- a/code/datums/diseases/fake_gbs.dm
+++ b/code/datums/diseases/fake_gbs.dm
@@ -2,13 +2,13 @@
 	name = "GBS"
 	max_stages = 5
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Synaptizine & Sulfur"
 	cures = list("synaptizine","sulfur")
 	agent = "Gravitokinetic Bipotential SADS-"
 	viable_mobtypes = list(/mob/living/carbon/human, /mob/living/carbon/monkey)
 	desc = "If left untreated death will occur."
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 
 /datum/disease/fake_gbs/stage_act()
 	..()
diff --git a/code/datums/diseases/flu.dm b/code/datums/diseases/flu.dm
index 99ea04b0556..206b61fb352 100644
--- a/code/datums/diseases/flu.dm
+++ b/code/datums/diseases/flu.dm
@@ -9,7 +9,7 @@
 	viable_mobtypes = list(/mob/living/carbon/human, /mob/living/carbon/monkey)
 	permeability_mod = 0.75
 	desc = "If left untreated the subject will feel quite unwell."
-	severity = MEDIUM
+	severity = VIRUS_SEVERITY_MINOR
 
 /datum/disease/flu/stage_act()
 	..()
diff --git a/code/datums/diseases/fluspanish.dm b/code/datums/diseases/fluspanish.dm
index 5a75201fafc..da75ef1db67 100644
--- a/code/datums/diseases/fluspanish.dm
+++ b/code/datums/diseases/fluspanish.dm
@@ -9,7 +9,7 @@
 	viable_mobtypes = list(/mob/living/carbon/human)
 	permeability_mod = 0.75
 	desc = "If left untreated the subject will burn to death for being a heretic."
-	severity = DANGEROUS
+	severity = VIRUS_SEVERITY_DANGEROUS
 
 /datum/disease/fluspanish/stage_act()
 	..()
diff --git a/code/datums/diseases/gbs.dm b/code/datums/diseases/gbs.dm
index c24dca947bf..77385ebac35 100644
--- a/code/datums/diseases/gbs.dm
+++ b/code/datums/diseases/gbs.dm
@@ -2,7 +2,7 @@
 	name = "GBS"
 	max_stages = 5
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Synaptizine & Sulfur"
 	cures = list("synaptizine","sulfur")
 	cure_chance = 15//higher chance to cure, since two reagents are required
@@ -10,7 +10,7 @@
 	viable_mobtypes = list(/mob/living/carbon/human)
 	disease_flags = CAN_CARRY|CAN_RESIST|CURABLE
 	permeability_mod = 1
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 
 /datum/disease/gbs/stage_act()
 	..()
diff --git a/code/datums/diseases/magnitis.dm b/code/datums/diseases/magnitis.dm
index 770f6bf313f..cc8204a717a 100644
--- a/code/datums/diseases/magnitis.dm
+++ b/code/datums/diseases/magnitis.dm
@@ -9,7 +9,7 @@
 	disease_flags = CAN_CARRY|CAN_RESIST|CURABLE
 	permeability_mod = 0.75
 	desc = "This disease disrupts the magnetic field of your body, making it act as if a powerful magnet. Injections of iron help stabilize the field."
-	severity = MEDIUM
+	severity = VIRUS_SEVERITY_MEDIUM
 
 /datum/disease/magnitis/stage_act()
 	..()
diff --git a/code/datums/diseases/parrotpossession.dm b/code/datums/diseases/parrotpossession.dm
index a5d87be9801..d19d05620c5 100644
--- a/code/datums/diseases/parrotpossession.dm
+++ b/code/datums/diseases/parrotpossession.dm
@@ -2,7 +2,7 @@
 	name = "Parrot Possession"
 	max_stages = 1
 	spread_text = "Paranormal"
-	spread_flags = SPECIAL
+	spread_flags = VIRUS_SPREAD_SPECIAL
 	disease_flags = CURABLE
 	cure_text = "Holy Water."
 	cures = list("holywater")
@@ -10,7 +10,7 @@
 	agent = "Avian Vengence"
 	viable_mobtypes = list(/mob/living/carbon/human)
 	desc = "Subject is possesed by the vengeful spirit of a parrot. Call the priest."
-	severity = MEDIUM
+	severity = VIRUS_SEVERITY_MEDIUM
 	var/mob/living/simple_animal/parrot/Poly/ghost/parrot
 
 /datum/disease/parrot_possession/stage_act()
diff --git a/code/datums/diseases/pierrot_throat.dm b/code/datums/diseases/pierrot_throat.dm
index ba2a43792f7..89dce445360 100644
--- a/code/datums/diseases/pierrot_throat.dm
+++ b/code/datums/diseases/pierrot_throat.dm
@@ -9,7 +9,7 @@
 	viable_mobtypes = list(/mob/living/carbon/human)
 	permeability_mod = 0.75
 	desc = "If left untreated the subject will probably drive others to insanity."
-	severity = MEDIUM
+	severity = VIRUS_SEVERITY_MEDIUM
 
 /datum/disease/pierrot_throat/stage_act()
 	..()
diff --git a/code/datums/diseases/retrovirus.dm b/code/datums/diseases/retrovirus.dm
index e8a8c48d8ef..ae5fa9655ff 100644
--- a/code/datums/diseases/retrovirus.dm
+++ b/code/datums/diseases/retrovirus.dm
@@ -2,13 +2,13 @@
 	name = "Retrovirus"
 	max_stages = 4
 	spread_text = "Contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Rest or an injection of mutadone"
 	cure_chance = 6
 	agent = ""
 	viable_mobtypes = list(/mob/living/carbon/human)
 	desc = "A DNA-altering retrovirus that scrambles the structural and unique enzymes of a host constantly."
-	severity = DANGEROUS
+	severity = VIRUS_SEVERITY_HARMFUL
 	permeability_mod = 0.4
 	stage_prob = 2
 	var/SE
diff --git a/code/datums/diseases/rhumba_beat.dm b/code/datums/diseases/rhumba_beat.dm
index 4c528b61b17..855f1f44f01 100644
--- a/code/datums/diseases/rhumba_beat.dm
+++ b/code/datums/diseases/rhumba_beat.dm
@@ -2,13 +2,13 @@
 	name = "The Rhumba Beat"
 	max_stages = 5
 	spread_text = "On contact"
-	spread_flags = CONTACT_GENERAL
+	spread_flags = VIRUS_SPREAD_BLOOD | VIRUS_SPREAD_CONTACT_SKIN | VIRUS_SPREAD_CONTACT_FLUIDS
 	cure_text = "Chick Chicky Boom!"
 	cures = list("plasma")
 	agent = "Unknown"
 	viable_mobtypes = list(/mob/living/carbon/human)
 	permeability_mod = 1
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 
 /datum/disease/rhumba_beat/stage_act()
 	..()
diff --git a/code/datums/diseases/transformation.dm b/code/datums/diseases/transformation.dm
index 77a56bc41ab..0ff47f854da 100644
--- a/code/datums/diseases/transformation.dm
+++ b/code/datums/diseases/transformation.dm
@@ -2,11 +2,11 @@
 	name = "Transformation"
 	max_stages = 5
 	spread_text = "Acute"
-	spread_flags = SPECIAL
+	spread_flags = VIRUS_SPREAD_SPECIAL
 	cure_text = "A coder's love (theoretical)."
 	agent = "Shenanigans"
 	viable_mobtypes = list(/mob/living/carbon/human, /mob/living/carbon/monkey, /mob/living/carbon/alien)
-	severity = HARMFUL
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	stage_prob = 10
 	visibility_flags = HIDDEN_SCANNER|HIDDEN_PANDEMIC
 	disease_flags = CURABLE
@@ -68,13 +68,13 @@
 	cure_text = "Bananas"
 	cures = list("banana")
 	spread_text = "Monkey Bites"
-	spread_flags = SPECIAL
+	spread_flags = VIRUS_SPREAD_SPECIAL
 	viable_mobtypes = list(/mob/living/carbon/monkey, /mob/living/carbon/human)
 	permeability_mod = 1
 	cure_chance = 1
 	disease_flags = CAN_CARRY|CAN_RESIST
 	desc = "Monkeys with this disease will bite humans, causing humans to mutate into a monkey."
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	stage_prob = 4
 	visibility_flags = 0
 	agent = "Kongey Vibrion M-909"
@@ -119,7 +119,7 @@
 	cure_chance = 5
 	agent = "R2D2 Nanomachines"
 	desc = "This disease, actually acute nanomachine infection, converts the victim into a cyborg."
-	severity = DANGEROUS
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	visibility_flags = 0
 	stage1	= null
 	stage2	= list("Your joints feel stiff.", "<span class='danger'>Beep...boop..</span>")
@@ -151,7 +151,7 @@
 	cure_chance = 5
 	agent = "Rip-LEY Alien Microbes"
 	desc = "This disease changes the victim into a xenomorph."
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	visibility_flags = 0
 	stage1	= null
 	stage2	= list("Your throat feels scratchy.", "<span class='danger'>Kill...</span>")
@@ -179,7 +179,7 @@
 	cure_chance = 80
 	agent = "Advanced Mutation Toxin"
 	desc = "This highly concentrated extract converts anything into more of itself."
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	visibility_flags = 0
 	stage1	= list("You don't feel very well.")
 	stage2	= list("Your skin feels a little slimy.")
@@ -206,6 +206,7 @@
 	cures = list("adminordrazine")
 	agent = "Fell Doge Majicks"
 	desc = "This disease transforms the victim into a corgi."
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	visibility_flags = 0
 	stage1	= list("BARK.")
 	stage2	= list("You feel the need to wear silly hats.")
@@ -231,7 +232,7 @@
 	agent = "Gluttony's Blessing"
 	desc = "A 'gift' from somewhere terrible."
 	stage_prob = 20
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	visibility_flags = 0
 	stage1	= list("Your stomach rumbles.")
 	stage2	= list("Your skin feels saggy.")
diff --git a/code/datums/diseases/tuberculosis.dm b/code/datums/diseases/tuberculosis.dm
index c8e2a4609be..d8f1a41c763 100644
--- a/code/datums/diseases/tuberculosis.dm
+++ b/code/datums/diseases/tuberculosis.dm
@@ -10,7 +10,7 @@
 	cure_chance = 5//like hell are you getting out of hell
 	desc = "A rare highly transmittable virulent virus. Few samples exist, rumoured to be carefully grown and cultured by clandestine bio-weapon specialists. Causes fever, blood vomiting, lung damage, weight loss, and fatigue."
 	required_organs = list(/obj/item/organ/lungs)
-	severity = DANGEROUS
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	bypasses_immunity = TRUE // TB primarily impacts the lungs; it's also bacterial or fungal in nature; viral immunity should do nothing.
 
 /datum/disease/tuberculosis/stage_act() //it begins
diff --git a/code/datums/diseases/wizarditis.dm b/code/datums/diseases/wizarditis.dm
index ae6e0835e71..612418b1caf 100644
--- a/code/datums/diseases/wizarditis.dm
+++ b/code/datums/diseases/wizarditis.dm
@@ -10,7 +10,7 @@
 	disease_flags = CAN_CARRY|CAN_RESIST|CURABLE
 	permeability_mod = 0.75
 	desc = "Some speculate that this virus is the cause of the Space Wizard Federation's existence. Subjects affected show the signs of mental retardation, yelling obscure sentences or total gibberish. On late stages subjects sometime express the feelings of inner power, and, cite, 'the ability to control the forces of cosmos themselves!' A gulp of strong, manly spirits usually reverts them to normal, humanlike, condition."
-	severity = HARMFUL
+	severity = VIRUS_SEVERITY_HARMFUL
 	required_organs = list(/obj/item/bodypart/head)
 
 /*
diff --git a/code/game/atoms.dm b/code/game/atoms.dm
index dae50e4a2f4..42c1a2f4bfa 100644
--- a/code/game/atoms.dm
+++ b/code/game/atoms.dm
@@ -412,10 +412,10 @@ GLOBAL_LIST_EMPTY(blood_splatter_icons)
 	. = ..()
 	transfer_blood = rand(2, 4)
 
-/turf/add_blood(list/blood_dna)
+/turf/add_blood(list/blood_dna, list/datum/disease/diseases)
 	var/obj/effect/decal/cleanable/blood/splatter/B = locate() in src
 	if(!B)
-		B = new /obj/effect/decal/cleanable/blood/splatter(src)
+		B = new /obj/effect/decal/cleanable/blood/splatter(src, diseases)
 	B.transfer_blood_dna(blood_dna) //give blood info to the blood decal.
 	return 1 //we bloodied the floor
 
@@ -525,7 +525,7 @@ GLOBAL_LIST_EMPTY(blood_splatter_icons)
 
 /atom/proc/add_vomit_floor(mob/living/carbon/M, toxvomit = 0)
 	if(isturf(src))
-		var/obj/effect/decal/cleanable/vomit/V = new /obj/effect/decal/cleanable/vomit(src)
+		var/obj/effect/decal/cleanable/vomit/V = new /obj/effect/decal/cleanable/vomit(src, M.get_static_viruses())
 		// Make toxins vomit look different
 		if(toxvomit)
 			V.icon_state = "vomittox_[pick(1,4)]"
diff --git a/code/game/data_huds.dm b/code/game/data_huds.dm
index 84255da890d..10ff185fd6e 100644
--- a/code/game/data_huds.dm
+++ b/code/game/data_huds.dm
@@ -66,16 +66,12 @@
 
 //called when a carbon changes virus
 /mob/living/carbon/proc/check_virus()
-	var/threat = 0
+	var/threat
 	for(var/thing in viruses)
 		var/datum/disease/D = thing
 		if(!(D.visibility_flags & HIDDEN_SCANNER))
-			if (D.severity != NONTHREAT) //a buffing virus gets an icon
-				threat = 2
-				return threat //harmful viruses have priority
-			else
-				threat = 1 //aka good virus
-
+			if(!threat || D.severity > threat) //a buffing virus gets an icon
+				threat = D.severity
 	return threat
 
 //helper for getting the appropriate health status
@@ -168,18 +164,30 @@
 /mob/living/carbon/med_hud_set_status()
 	var/image/holder = hud_list[STATUS_HUD]
 	var/icon/I = icon(icon, icon_state, dir)
-	var/virus_state = check_virus()
+	var/virus_threat = check_virus()
 	holder.pixel_y = I.Height() - world.icon_size
 	if(status_flags & XENO_HOST)
 		holder.icon_state = "hudxeno"
 	else if(stat == DEAD || (status_flags & FAKEDEATH))
 		holder.icon_state = "huddead"
-	else if(virus_state == 2)
-		holder.icon_state = "hudill"
-	else if(virus_state == 1)
-		holder.icon_state = "hudbuff"
 	else
-		holder.icon_state = "hudhealthy"
+		switch(virus_threat)
+			if(VIRUS_SEVERITY_BIOHAZARD)
+				holder.icon_state = "hudill5"
+			if(VIRUS_SEVERITY_DANGEROUS)
+				holder.icon_state = "hudill4"
+			if(VIRUS_SEVERITY_HARMFUL)
+				holder.icon_state = "hudill3"
+			if(VIRUS_SEVERITY_MEDIUM)
+				holder.icon_state = "hudill2"
+			if(VIRUS_SEVERITY_MINOR)
+				holder.icon_state = "hudill1"
+			if(VIRUS_SEVERITY_NONTHREAT)
+				holder.icon_state = "hudill0"
+			if(VIRUS_SEVERITY_POSITIVE)
+				holder.icon_state = "hudbuff"
+			if(null)
+				holder.icon_state = "hudhealthy"
 
 
 /***********************************************
diff --git a/code/game/gamemodes/changeling/powers/panacea.dm b/code/game/gamemodes/changeling/powers/panacea.dm
index fa17dde687a..829b0a85125 100644
--- a/code/game/gamemodes/changeling/powers/panacea.dm
+++ b/code/game/gamemodes/changeling/powers/panacea.dm
@@ -32,7 +32,7 @@
 
 	for(var/thing in user.viruses)
 		var/datum/disease/D = thing
-		if(D.severity == NONTHREAT)
+		if(D.severity == VIRUS_SEVERITY_POSITIVE)
 			continue
 		D.cure()
 	return TRUE
diff --git a/code/game/gamemodes/miniantags/revenant/revenant_blight.dm b/code/game/gamemodes/miniantags/revenant/revenant_blight.dm
index 913efb34ce8..21bc534f273 100644
--- a/code/game/gamemodes/miniantags/revenant/revenant_blight.dm
+++ b/code/game/gamemodes/miniantags/revenant/revenant_blight.dm
@@ -2,7 +2,7 @@
 	name = "Unnatural Wasting"
 	max_stages = 5
 	stage_prob = 10
-	spread_flags = NON_CONTAGIOUS
+	spread_flags = VIRUS_SPREAD_NON_CONTAGIOUS
 	cure_text = "Holy water or extensive rest."
 	spread_text = "A burst of unholy energy"
 	cures = list("holywater")
@@ -11,7 +11,7 @@
 	viable_mobtypes = list(/mob/living/carbon/human)
 	disease_flags = CURABLE
 	permeability_mod = 1
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_HARMFUL
 	var/stagedamage = 0 //Highest stage reached.
 	var/finalstage = 0 //Because we're spawning off the cure in the final stage, we need to check if we've done the final stage's effects.
 
diff --git a/code/game/objects/effects/decals/cleanable.dm b/code/game/objects/effects/decals/cleanable.dm
index 2aca5c534bb..4a5ac2f60d1 100644
--- a/code/game/objects/effects/decals/cleanable.dm
+++ b/code/game/objects/effects/decals/cleanable.dm
@@ -6,7 +6,7 @@
 	var/bloodiness = 0 //0-100, amount of blood in this decal, used for making footprints and affecting the alpha of bloody footprints
 	var/mergeable_decal = 1 //when two of these are on a same tile or do we need to merge them into just one?
 
-/obj/effect/decal/cleanable/Initialize(mapload)
+/obj/effect/decal/cleanable/Initialize(mapload, list/datum/disease/diseases)
 	if (random_icon_states && length(src.random_icon_states) > 0)
 		src.icon_state = pick(src.random_icon_states)
 	create_reagents(300)
@@ -14,10 +14,15 @@
 		for(var/obj/effect/decal/cleanable/C in src.loc)
 			if(C != src && C.type == src.type)
 				replace_decal(C)
+	if(LAZYLEN(diseases))
+		var/list/datum/disease/diseases_to_add = list()
+		for(var/datum/disease/D in diseases)
+			if(D.spread_flags & VIRUS_SPREAD_CONTACT_FLUIDS)
+				diseases_to_add += D
+		if(LAZYLEN(diseases_to_add))
+			AddComponent(/datum/component/infective, diseases_to_add)
 	. = ..()
 
-
-
 /obj/effect/decal/cleanable/proc/replace_decal(obj/effect/decal/cleanable/C)
 	if(mergeable_decal)
 		qdel(C)
@@ -65,6 +70,7 @@
 //Add "bloodiness" of this blood's type, to the human's shoes
 //This is on /cleanable because fuck this ancient mess
 /obj/effect/decal/cleanable/Crossed(atom/movable/O)
+	..()
 	if(ishuman(O))
 		var/mob/living/carbon/human/H = O
 		if(H.shoes && blood_state && bloodiness)
diff --git a/code/game/objects/effects/decals/cleanable/humans.dm b/code/game/objects/effects/decals/cleanable/humans.dm
index 5566a91d886..dfb3567b11a 100644
--- a/code/game/objects/effects/decals/cleanable/humans.dm
+++ b/code/game/objects/effects/decals/cleanable/humans.dm
@@ -18,7 +18,7 @@
 	desc = "Looks like it's been here a while.  Eew."
 	bloodiness = 0
 
-/obj/effect/decal/cleanable/blood/old/Initialize()
+/obj/effect/decal/cleanable/blood/old/Initialize(mapload, list/datum/disease/diseases)
 	. = ..()
 	icon_state += "-old" //This IS necessary because the parent /blood type uses icon randomization.
 	blood_DNA["Non-human DNA"] = "A+"
@@ -39,7 +39,6 @@
 	var/list/existing_dirs = list()
 	blood_DNA = list()
 
-
 /obj/effect/decal/cleanable/trail_holder/can_bloodcrawl_in()
 	return 1
 
@@ -53,7 +52,7 @@
 	random_icon_states = list("gib1", "gib2", "gib3", "gib4", "gib5", "gib6")
 	mergeable_decal = 0
 
-/obj/effect/decal/cleanable/blood/gibs/Initialize()
+/obj/effect/decal/cleanable/blood/gibs/Initialize(mapload, list/datum/disease/diseases)
 	. = ..()
 	reagents.add_reagent("liquidgibs", 5)
 
@@ -66,7 +65,11 @@
 	for(var/i = 0, i < pick(1, 200; 2, 150; 3, 50), i++)
 		sleep(2)
 		if(i > 0)
-			new /obj/effect/decal/cleanable/blood/splatter(loc)
+			var/list/datum/disease/diseases
+			GET_COMPONENT(infective, /datum/component/infective)
+			if(infective)
+				diseases = infective.diseases
+			new /obj/effect/decal/cleanable/blood/splatter(loc, diseases)
 		if(!step_to(src, get_step(src, direction), 0))
 			break
 
@@ -93,7 +96,7 @@
 	desc = "Space Jesus, why didn't anyone clean this up?  It smells terrible."
 	bloodiness = 0
 
-/obj/effect/decal/cleanable/blood/gibs/old/Initialize()
+/obj/effect/decal/cleanable/blood/gibs/old/Initialize(mapload, list/datum/disease/diseases)
 	. = ..()
 	setDir(pick(1,2,4,8))
 	icon_state += "-old"
@@ -126,6 +129,7 @@
 	var/list/shoe_types = list()
 
 /obj/effect/decal/cleanable/blood/footprints/Crossed(atom/movable/O)
+	..()
 	if(ishuman(O))
 		var/mob/living/carbon/human/H = O
 		var/obj/item/clothing/shoes/S = H.shoes
@@ -136,6 +140,7 @@
 	update_icon()
 
 /obj/effect/decal/cleanable/blood/footprints/Uncrossed(atom/movable/O)
+	..()
 	if(ishuman(O))
 		var/mob/living/carbon/human/H = O
 		var/obj/item/clothing/shoes/S = H.shoes
diff --git a/code/game/objects/effects/decals/cleanable/misc.dm b/code/game/objects/effects/decals/cleanable/misc.dm
index 4be49d12f8b..583f63af3a9 100644
--- a/code/game/objects/effects/decals/cleanable/misc.dm
+++ b/code/game/objects/effects/decals/cleanable/misc.dm
@@ -101,7 +101,7 @@
 	name = "crusty dried vomit"
 	desc = "You try not to look at the chunks, and fail."
 
-/obj/effect/decal/cleanable/vomit/old/Initialize()
+/obj/effect/decal/cleanable/vomit/old/Initialize(mapload, list/datum/disease/diseases)
 	. = ..()
 	icon_state += "-old"
 
diff --git a/code/game/objects/effects/spawners/gibspawner.dm b/code/game/objects/effects/spawners/gibspawner.dm
index 4750e2c5278..b5e20dd399e 100644
--- a/code/game/objects/effects/spawners/gibspawner.dm
+++ b/code/game/objects/effects/spawners/gibspawner.dm
@@ -6,7 +6,7 @@
 	var/list/gibamounts = list() //amount to spawn for each gib decal type we'll spawn.
 	var/list/gibdirections = list() //of lists of possible directions to spread each gib decal type towards.
 
-/obj/effect/gibspawner/Initialize(mapload, datum/dna/MobDNA)
+/obj/effect/gibspawner/Initialize(mapload, datum/dna/MobDNA, list/datum/disease/diseases)
 	. = ..()
 
 	if(gibtypes.len != gibamounts.len || gibamounts.len != gibdirections.len)
@@ -24,7 +24,7 @@
 		if(gibamounts[i])
 			for(var/j = 1, j<= gibamounts[i], j++)
 				var/gibType = gibtypes[i]
-				gib = new gibType(loc)
+				gib = new gibType(loc, diseases)
 				if(iscarbon(loc))
 					var/mob/living/carbon/digester = loc
 					digester.stomach_contents += gib
diff --git a/code/modules/clothing/shoes/magboots.dm b/code/modules/clothing/shoes/magboots.dm
index 9e89176f728..27b5462b567 100644
--- a/code/modules/clothing/shoes/magboots.dm
+++ b/code/modules/clothing/shoes/magboots.dm
@@ -5,6 +5,7 @@
 	var/magboot_state = "magboots"
 	var/magpulse = 0
 	var/slowdown_active = 2
+	permeability_coefficient = 0.05
 	actions_types = list(/datum/action/item_action/toggle)
 	strip_delay = 70
 	equip_delay_other = 70
diff --git a/code/modules/clothing/shoes/miscellaneous.dm b/code/modules/clothing/shoes/miscellaneous.dm
index 766742027f1..d086139ee89 100644
--- a/code/modules/clothing/shoes/miscellaneous.dm
+++ b/code/modules/clothing/shoes/miscellaneous.dm
@@ -23,6 +23,7 @@
 	armor = list(melee = 25, bullet = 25, laser = 25, energy = 25, bomb = 50, bio = 10, rad = 0, fire = 70, acid = 50)
 	strip_delay = 70
 	resistance_flags = 0
+	permeability_coefficient = 0.05 //Thick soles, and covers the ankle
 	pockets = /obj/item/storage/internal/pocket/shoes
 
 /obj/item/clothing/shoes/combat/swat //overpowered boots for death squads
@@ -38,6 +39,7 @@
 	icon_state = "wizard"
 	strip_delay = 50
 	equip_delay_other = 50
+	permeability_coefficient = 0.9
 
 /obj/item/clothing/shoes/sandal/marisa
 	desc = "A pair of magic black shoes."
@@ -54,7 +56,7 @@
 	desc = "A pair of yellow rubber boots, designed to prevent slipping on wet surfaces."
 	name = "galoshes"
 	icon_state = "galoshes"
-	permeability_coefficient = 0.05
+	permeability_coefficient = 0.01
 	flags_1 = NOSLIP_1
 	slowdown = SHOES_SLOWDOWN+1
 	strip_delay = 50
@@ -102,6 +104,7 @@
 	strip_delay = 50
 	equip_delay_other = 50
 	resistance_flags = 0
+	permeability_coefficient = 0.05 //Thick soles, and covers the ankle
 	pockets = /obj/item/storage/internal/pocket/shoes
 
 /obj/item/clothing/shoes/jackboots/fast
@@ -112,6 +115,7 @@
 	desc = "Boots lined with 'synthetic' animal fur."
 	icon_state = "winterboots"
 	item_state = "winterboots"
+	permeability_coefficient = 0.15
 	cold_protection = FEET|LEGS
 	min_cold_protection_temperature = SHOES_MIN_TEMP_PROTECT
 	heat_protection = FEET|LEGS
@@ -125,6 +129,7 @@
 	item_state = "jackboots"
 	lefthand_file = 'icons/mob/inhands/equipment/security_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/equipment/security_righthand.dmi'
+	permeability_coefficient = 0.15
 	strip_delay = 40
 	equip_delay_other = 40
 	pockets = /obj/item/storage/internal/pocket/shoes
@@ -171,6 +176,7 @@
 	item_state = "roman"
 	strip_delay = 100
 	equip_delay_other = 100
+	permeability_coefficient = 0.9
 
 /obj/item/clothing/shoes/griffin
 	name = "griffon boots"
@@ -188,6 +194,7 @@
 	resistance_flags = FIRE_PROOF
 	pockets = /obj/item/storage/internal/pocket/shoes
 	actions_types = list(/datum/action/item_action/bhop)
+	permeability_coefficient = 0.05
 	var/jumpdistance = 5 //-1 from to see the actual distance, e.g 4 goes over 3 tiles
 	var/jumpspeed = 3
 	var/recharging_rate = 60 //default 6 seconds between each dash
diff --git a/code/modules/clothing/spacesuits/flightsuit.dm b/code/modules/clothing/spacesuits/flightsuit.dm
index 18f45f45040..12f8eab51c8 100644
--- a/code/modules/clothing/spacesuits/flightsuit.dm
+++ b/code/modules/clothing/spacesuits/flightsuit.dm
@@ -847,6 +847,7 @@
 	var/obj/item/device/flightpack/pack = null
 	var/mob/living/carbon/human/wearer = null
 	var/active = FALSE
+	permeability_coefficient = 0.01
 	resistance_flags = FIRE_PROOF | ACID_PROOF
 
 /obj/item/clothing/shoes/flightshoes/Destroy()
diff --git a/code/modules/food_and_drinks/kitchen_machinery/gibber.dm b/code/modules/food_and_drinks/kitchen_machinery/gibber.dm
index b1eb0f2f721..372c085adb1 100644
--- a/code/modules/food_and_drinks/kitchen_machinery/gibber.dm
+++ b/code/modules/food_and_drinks/kitchen_machinery/gibber.dm
@@ -147,6 +147,7 @@
 
 	var/obj/item/reagent_containers/food/snacks/meat/slab/allmeat[meat_produced]
 	var/obj/item/stack/sheet/animalhide/skin
+	var/list/datum/disease/diseases = mob_occupant.get_static_viruses()
 
 	if(ishuman(occupant))
 		var/mob/living/carbon/human/gibee = occupant
@@ -180,26 +181,28 @@
 	mob_occupant.death(1)
 	mob_occupant.ghostize()
 	qdel(src.occupant)
-	spawn(src.gibtime)
-		playsound(src.loc, 'sound/effects/splat.ogg', 50, 1)
-		operating = FALSE
-		var/turf/T = get_turf(src)
-		var/list/turf/nearby_turfs = RANGE_TURFS(3,T) - T
-		if(skin)
-			skin.forceMove(loc)
-			skin.throw_at(pick(nearby_turfs),meat_produced,3)
-		for (var/i=1 to meat_produced)
-			var/obj/item/meatslab = allmeat[i]
-			meatslab.forceMove(loc)
-			meatslab.throw_at(pick(nearby_turfs),i,3)
-			for (var/turfs=1 to meat_produced)
-				var/turf/gibturf = pick(nearby_turfs)
-				if (!gibturf.density && src in view(gibturf))
-					new gibtype(gibturf,i)
+	addtimer(CALLBACK(src, .proc/make_meat, skin, allmeat, meat_produced, gibtype, diseases), gibtime)
 
-		pixel_x = initial(pixel_x) //return to its spot after shaking
-		operating = FALSE
-		update_icon()
+/obj/machinery/gibber/proc/make_meat(obj/item/stack/sheet/animalhide/skin, list/obj/item/reagent_containers/food/snacks/meat/slab/allmeat, meat_produced, gibtype, list/datum/disease/diseases)
+	playsound(src.loc, 'sound/effects/splat.ogg', 50, 1)
+	operating = FALSE
+	var/turf/T = get_turf(src)
+	var/list/turf/nearby_turfs = RANGE_TURFS(3,T) - T
+	if(skin)
+		skin.forceMove(loc)
+		skin.throw_at(pick(nearby_turfs),meat_produced,3)
+	for (var/i=1 to meat_produced)
+		var/obj/item/meatslab = allmeat[i]
+		meatslab.forceMove(loc)
+		meatslab.throw_at(pick(nearby_turfs),i,3)
+		for (var/turfs=1 to meat_produced)
+			var/turf/gibturf = pick(nearby_turfs)
+			if (!gibturf.density && src in view(gibturf))
+				new gibtype(gibturf,i,diseases)
+
+	pixel_x = initial(pixel_x) //return to its spot after shaking
+	operating = FALSE
+	update_icon()
 
 //auto-gibs anything that bumps into it
 /obj/machinery/gibber/autogibber
diff --git a/code/modules/food_and_drinks/kitchen_machinery/processor.dm b/code/modules/food_and_drinks/kitchen_machinery/processor.dm
index fb871f2c3a4..0699e225475 100644
--- a/code/modules/food_and_drinks/kitchen_machinery/processor.dm
+++ b/code/modules/food_and_drinks/kitchen_machinery/processor.dm
@@ -135,7 +135,7 @@
 
 	for(var/thing in O.viruses)
 		var/datum/disease/D = thing
-		if(!(D.spread_flags & SPECIAL))
+		if(!(D.spread_flags & VIRUS_SPREAD_SPECIAL))
 			B.data["viruses"] += D.Copy()
 	if(O.has_dna())
 		B.data["blood_DNA"] = O.dna.unique_enzymes
diff --git a/code/modules/mining/lavaland/necropolis_chests.dm b/code/modules/mining/lavaland/necropolis_chests.dm
index 5ab687cc665..7884dcec756 100644
--- a/code/modules/mining/lavaland/necropolis_chests.dm
+++ b/code/modules/mining/lavaland/necropolis_chests.dm
@@ -846,7 +846,7 @@
 	agent = "dragon's blood"
 	desc = "What do dragons have to do with Space Station 13?"
 	stage_prob = 20
-	severity = BIOHAZARD
+	severity = VIRUS_SEVERITY_BIOHAZARD
 	visibility_flags = 0
 	stage1	= list("Your bones ache.")
 	stage2	= list("Your skin feels scaly.")
diff --git a/code/modules/mob/living/blood.dm b/code/modules/mob/living/blood.dm
index 8e547eeb120..30d5652ab40 100644
--- a/code/modules/mob/living/blood.dm
+++ b/code/modules/mob/living/blood.dm
@@ -139,7 +139,7 @@
 				if(blood_data["viruses"])
 					for(var/thing in blood_data["viruses"])
 						var/datum/disease/D = thing
-						if((D.spread_flags & SPECIAL) || (D.spread_flags & NON_CONTAGIOUS))
+						if((D.spread_flags & VIRUS_SPREAD_SPECIAL) || (D.spread_flags & VIRUS_SPREAD_NON_CONTAGIOUS))
 							continue
 						C.ForceContractDisease(D)
 				if(!(blood_data["blood_type"] in get_safe_blood(C.dna.blood_type)))
@@ -258,14 +258,14 @@
 				temp_blood_DNA |= drop.blood_DNA.Copy() //we transfer the dna from the drip to the splatter
 				qdel(drop)//the drip is replaced by a bigger splatter
 		else
-			drop = new(T)
+			drop = new(T, get_static_viruses())
 			drop.transfer_mob_blood_dna(src)
 			return
 
 	// Find a blood decal or create a new one.
 	var/obj/effect/decal/cleanable/blood/B = locate() in T
 	if(!B)
-		B = new /obj/effect/decal/cleanable/blood/splatter(T)
+		B = new /obj/effect/decal/cleanable/blood/splatter(T, get_static_viruses())
 	B.transfer_mob_blood_dna(src) //give blood info to the blood decal.
 	if(temp_blood_DNA)
 		B.blood_DNA |= temp_blood_DNA
diff --git a/code/modules/mob/living/carbon/carbon.dm b/code/modules/mob/living/carbon/carbon.dm
index 5502a28a3b6..1475c98cd5f 100644
--- a/code/modules/mob/living/carbon/carbon.dm
+++ b/code/modules/mob/living/carbon/carbon.dm
@@ -750,7 +750,7 @@
 		B.damaged_brain = 0
 	for(var/thing in viruses)
 		var/datum/disease/D = thing
-		if(D.severity != NONTHREAT)
+		if(D.severity != VIRUS_SEVERITY_POSITIVE)
 			D.cure(0)
 	if(admin_revive)
 		regenerate_limbs()
diff --git a/code/modules/mob/living/carbon/carbon_defense.dm b/code/modules/mob/living/carbon/carbon_defense.dm
index 8a3ea44afa2..8b818fad130 100644
--- a/code/modules/mob/living/carbon/carbon_defense.dm
+++ b/code/modules/mob/living/carbon/carbon_defense.dm
@@ -112,13 +112,13 @@
 
 	for(var/thing in viruses)
 		var/datum/disease/D = thing
-		if(D.IsSpreadByTouch())
-			user.ContractDisease(D)
+		if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+			user.ContactContractDisease(D)
 
 	for(var/thing in user.viruses)
 		var/datum/disease/D = thing
-		if(D.IsSpreadByTouch())
-			ContractDisease(D)
+		if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+			ContactContractDisease(D)
 
 	if(lying && surgeries.len)
 		if(user.a_intent == INTENT_HELP)
@@ -131,13 +131,13 @@
 /mob/living/carbon/attack_paw(mob/living/carbon/monkey/M)
 	for(var/thing in viruses)
 		var/datum/disease/D = thing
-		if(D.IsSpreadByTouch())
-			M.ContractDisease(D)
+		if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+			M.ContactContractDisease(D)
 
 	for(var/thing in M.viruses)
 		var/datum/disease/D = thing
-		if(D.IsSpreadByTouch())
-			ContractDisease(D)
+		if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+			ContactContractDisease(D)
 
 	if(M.a_intent == INTENT_HELP)
 		help_shake_act(M)
diff --git a/code/modules/mob/living/carbon/human/death.dm b/code/modules/mob/living/carbon/human/death.dm
index 282de04ede3..c3ae5c39c3f 100644
--- a/code/modules/mob/living/carbon/human/death.dm
+++ b/code/modules/mob/living/carbon/human/death.dm
@@ -6,9 +6,9 @@
 
 /mob/living/carbon/human/spawn_gibs(with_bodyparts)
 	if(with_bodyparts)
-		new /obj/effect/gibspawner/human(get_turf(src), dna)
+		new /obj/effect/gibspawner/human(get_turf(src), dna, get_static_viruses())
 	else
-		new /obj/effect/gibspawner/humanbodypartless(get_turf(src), dna)
+		new /obj/effect/gibspawner/humanbodypartless(get_turf(src), dna, get_static_viruses())
 
 /mob/living/carbon/human/spawn_dust(just_ash = FALSE)
 	if(just_ash)
diff --git a/code/modules/mob/living/death.dm b/code/modules/mob/living/death.dm
index 40219161c66..c38ab397c86 100644
--- a/code/modules/mob/living/death.dm
+++ b/code/modules/mob/living/death.dm
@@ -18,7 +18,7 @@
 	return
 
 /mob/living/proc/spawn_gibs()
-	new /obj/effect/gibspawner/generic(get_turf(src))
+	new /obj/effect/gibspawner/generic(get_turf(src), null, get_static_viruses())
 
 /mob/living/proc/spill_organs()
 	return
diff --git a/code/modules/mob/living/living.dm b/code/modules/mob/living/living.dm
index 124c9e99af4..62ab3ac17e1 100644
--- a/code/modules/mob/living/living.dm
+++ b/code/modules/mob/living/living.dm
@@ -108,6 +108,17 @@
 	//Even if we don't push/swap places, we "touched" them, so spread fire
 	spreadFire(M)
 
+	//Also diseases
+	for(var/thing in viruses)
+		var/datum/disease/D = thing
+		if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+			M.ContactContractDisease(D)
+
+	for(var/thing in M.viruses)
+		var/datum/disease/D = thing
+		if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+			ContactContractDisease(D)
+
 	if(now_pushing)
 		return 1
 
@@ -507,7 +518,7 @@
 				if((newdir in GLOB.cardinals) && (prob(50)))
 					newdir = turn(get_dir(target_turf, start), 180)
 				if(!blood_exists)
-					new /obj/effect/decal/cleanable/trail_holder(start)
+					new /obj/effect/decal/cleanable/trail_holder(start, get_static_viruses())
 
 				for(var/obj/effect/decal/cleanable/trail_holder/TH in start)
 					if((!(newdir in TH.existing_dirs) || trail_type == "trails_1" || trail_type == "trails_2") && TH.existing_dirs.len <= 16) //maximum amount of overlays is 16 (all light & heavy directions filled)
diff --git a/code/modules/mob/living/simple_animal/bot/medbot.dm b/code/modules/mob/living/simple_animal/bot/medbot.dm
index 3a46e46bebb..8f8e574de5d 100644
--- a/code/modules/mob/living/simple_animal/bot/medbot.dm
+++ b/code/modules/mob/living/simple_animal/bot/medbot.dm
@@ -376,8 +376,8 @@
 			var/datum/disease/D = thing
 			//the medibot can't detect viruses that are undetectable to Health Analyzers or Pandemic machines.
 			if(!(D.visibility_flags & HIDDEN_SCANNER || D.visibility_flags & HIDDEN_PANDEMIC) \
-			&& D.severity != NONTHREAT \
-			&& (D.stage > 1 || (D.spread_flags & AIRBORNE))) // medibot can't detect a virus in its initial stage unless it spreads airborne.
+			&& D.severity != VIRUS_SEVERITY_POSITIVE \
+			&& (D.stage > 1 || (D.spread_flags & VIRUS_SPREAD_AIRBORNE))) // medibot can't detect a virus in its initial stage unless it spreads airborne.
 				return 1 //STOP DISEASE FOREVER
 
 	return 0
@@ -428,8 +428,8 @@
 				var/datum/disease/D = thing
 				//detectable virus
 				if((!(D.visibility_flags & HIDDEN_SCANNER)) || (!(D.visibility_flags & HIDDEN_PANDEMIC)))
-					if(D.severity != NONTHREAT)      //virus is harmful
-						if((D.stage > 1) || (D.spread_flags & AIRBORNE))
+					if(D.severity != VIRUS_SEVERITY_POSITIVE)      //virus is harmful
+						if((D.stage > 1) || (D.spread_flags & VIRUS_SPREAD_AIRBORNE))
 							virus = 1
 
 			if(!reagent_id && (virus))
diff --git a/code/modules/mob/living/simple_animal/parrot.dm b/code/modules/mob/living/simple_animal/parrot.dm
index 5f54710d8da..24ac9a59ba3 100644
--- a/code/modules/mob/living/simple_animal/parrot.dm
+++ b/code/modules/mob/living/simple_animal/parrot.dm
@@ -999,7 +999,7 @@
 	var/datum/disease/parrot_possession/P = new
 	P.parrot = src
 	loc = H
-	H.ContractDisease(P)
+	H.ForceContractDisease(P)
 	parrot_interest = null
 	H.visible_message("<span class='danger'>[src] dive bombs into [H]'s chest and vanishes!</span>", "<span class='userdanger'>[src] dive bombs into your chest, vanishing! This can't be good!</span>")
 
diff --git a/code/modules/mob/mob.dm b/code/modules/mob/mob.dm
index d5a00c9bb2b..8823c49b2f7 100644
--- a/code/modules/mob/mob.dm
+++ b/code/modules/mob/mob.dm
@@ -338,6 +338,18 @@
 
 	if(ismob(AM))
 		var/mob/M = AM
+
+		//Share diseases that are spread by touch
+		for(var/thing in viruses)
+			var/datum/disease/D = thing
+			if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+				M.ContactContractDisease(D)
+
+		for(var/thing in M.viruses)
+			var/datum/disease/D = thing
+			if(D.spread_flags & VIRUS_SPREAD_CONTACT_SKIN)
+				ContactContractDisease(D)
+
 		add_logs(src, M, "grabbed", addition="passive grab")
 		if(!supress_message)
 			visible_message("<span class='warning'>[src] has grabbed [M] passively!</span>")
@@ -936,6 +948,16 @@
 /mob/proc/get_idcard()
 	return
 
+/mob/proc/get_static_viruses() //used when creating blood and other infective objects
+	if(!LAZYLEN(viruses))
+		return
+	var/list/datum/disease/diseases = list()
+	for(var/datum/disease/D in viruses)
+		var/static_virus = D.Copy()
+		diseases += static_virus
+	return diseases
+
+
 /mob/vv_get_dropdown()
 	. = ..()
 	. += "---"
diff --git a/code/modules/reagents/chemistry/reagents/medicine_reagents.dm b/code/modules/reagents/chemistry/reagents/medicine_reagents.dm
index aa85a9dfaf8..9214979d4cf 100644
--- a/code/modules/reagents/chemistry/reagents/medicine_reagents.dm
+++ b/code/modules/reagents/chemistry/reagents/medicine_reagents.dm
@@ -61,7 +61,7 @@
 	M.jitteriness = 0
 	for(var/thing in M.viruses)
 		var/datum/disease/D = thing
-		if(D.severity == NONTHREAT)
+		if(D.severity == VIRUS_SEVERITY_POSITIVE)
 			continue
 		D.cure()
 	..()
diff --git a/code/modules/reagents/chemistry/reagents/other_reagents.dm b/code/modules/reagents/chemistry/reagents/other_reagents.dm
index 0f4b2859f8c..d602554752f 100644
--- a/code/modules/reagents/chemistry/reagents/other_reagents.dm
+++ b/code/modules/reagents/chemistry/reagents/other_reagents.dm
@@ -16,11 +16,11 @@
 		for(var/thing in data["viruses"])
 			var/datum/disease/D = thing
 
-			if((D.spread_flags & SPECIAL) || (D.spread_flags & NON_CONTAGIOUS))
+			if((D.spread_flags & VIRUS_SPREAD_SPECIAL) || (D.spread_flags & VIRUS_SPREAD_NON_CONTAGIOUS))
 				continue
 
-			if(method == TOUCH || method == VAPOR)
-				M.ContractDisease(D)
+			if((method == TOUCH || method == VAPOR) && (D.spread_flags & VIRUS_SPREAD_CONTACT_FLUIDS))
+				M.ContactContractDisease(D)
 			else //ingest, patch or inject
 				M.ForceContractDisease(D)
 
@@ -1060,7 +1060,7 @@
 
 /datum/reagent/xenomicrobes/reaction_mob(mob/M, method=TOUCH, reac_volume, show_message = 1, touch_protection = 0)
 	if(method==PATCH || method==INGEST || method==INJECT || (method == VAPOR && prob(min(reac_volume,100)*(1 - touch_protection))))
-		M.ContractDisease(new /datum/disease/transformation/xeno(0))
+		M.ForceContractDisease(new /datum/disease/transformation/xeno(0))
 
 /datum/reagent/fungalspores
 	name = "Tubercle bacillus Cosmosis microbes"
diff --git a/icons/mob/hud.dmi b/icons/mob/hud.dmi
index 3241635dba2..70988dbef5d 100644
Binary files a/icons/mob/hud.dmi and b/icons/mob/hud.dmi differ
diff --git a/tgstation.dme b/tgstation.dme
index 387d1afbf54..8b5e04333c8 100755
--- a/tgstation.dme
+++ b/tgstation.dme
@@ -36,6 +36,7 @@
 #include "code\__DEFINES\construction.dm"
 #include "code\__DEFINES\contracts.dm"
 #include "code\__DEFINES\cult.dm"
+#include "code\__DEFINES\diseases.dm"
 #include "code\__DEFINES\DNA.dm"
 #include "code\__DEFINES\events.dm"
 #include "code\__DEFINES\flags.dm"
@@ -260,6 +261,7 @@
 #include "code\datums\antagonists\ninja.dm"
 #include "code\datums\components\_component.dm"
 #include "code\datums\components\archaeology.dm"
+#include "code\datums\components\infective.dm"
 #include "code\datums\components\material_container.dm"
 #include "code\datums\components\paintable.dm"
 #include "code\datums\components\slippery.dm"