ContagionSpell, AoE, Chaos, Duration Tier: 1 Level: 1 Cast Time: 1.00 secAffects a single enemy with a Debuff that deals Chaos damage over time. If the enemy dies while affected by Contagion, it and all other Chaos damage over time Debuffs spread to nearby enemies and refresh their durations. Reanimating or detonating a corpse affected by Contagion will cause the Minion or explosion to spread Contagion on hit.Deals 1.8 Base Chaos Damage per second Modifiers to Spell Damage apply to Debuff's Damage over Time Debuff deals 100% more damage for each time it has spread, up to 300% Spread radius is 1.7 metres Debuff duration is 5 seconds
Additional Effects From 1-20% Quality: Debuff deals 0% more damage for each time it has spread, up to (0-100)%Skills can be managed in the Skills Panel.
Acquisition Drop restricted It can be obtained by engraving an Uncut Skill Gem.Metadata Item class: Skill Gem Metadata ID: Metadata/Items/Gems/SkillGemContagion
Contagion is an AoEChaosDurationSpellSkill that applies a spreading ChaosDamage over timeDebuff. Enemies killed while having the debuff will spread Contagion and any other Chaos damage over time debuffs on them to nearby enemies.
Contagion also spreads curses similarly to the damage over time debuff regardless of whether or not Decaying Hex is linked to the curse.[1][2] This is particularly synergistic with Despair or Temporal Chains.
Gem level progression
Level
1
Recommended support gems
The following support gems are recommendations by GGG as listed in-game, and do not necessarily reflect optimal combinations or the views of the wiki.
Many Skills have had their base damage and/or damage growth per level rebalanced. Most of these changes are not specifically mentioned below as the changes are too widespread.
Increased the damage growth per level on Essence Drain, Contagion, Profane Ritual and Chaos Bolt (Wand Skill). Results in approximately 33% more damage at Gem Level 25.
Essence DrainProjectile, Chaos, Duration Tier: 3 Level: 1 Critical Strike Chance: 7.00%Fires a Projectile that applies a powerful Chaos damage over time debuff to enemies it hits.Deals (5–126) to (9–234) Chaos Damage Modifiers to Spell Damage apply to Debuff's Damage over Time Debuff duration is 4 seconds Deals (8–217.5) Base Chaos Damage per second
Additional Effects From 1-20% Quality: Debuff Duration is (0-1) secondsSkills can be managed in the Skills Panel.Decaying HexSupport, Chaos, Curse Tier: 1 Cost & Reservation Multiplier: 130%Support Requirements: +5 IntSupports Curse skills. Cursed enemies' bodies decay, taking Chaos damage over time.Supported Skills inflict Decay, dealing 100% of Intelligence as Chaos damage per second for 8 secondsPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.DespairAoE, Chaos, Duration, Curse Tier: 9 Level: (1-20) Cost: (42-251) ManaCurses all targets in an area after a short delay, lowering their Chaos Resistance.Curse applies after 1 second delay Cursed enemies have (-36-30)% to Chaos Resistance Curse radius is (1.5–2.1) metres Curse duration is (6–7.4) seconds
Additional Effects From 1-20% Quality: Curse radius is (0–0.2) metersSkills can be managed in the Skills Panel.Temporal ChainsAoE, Duration, Curse Tier: 13 Level: 1Curses all enemies in an area, Slowing them and making other effects on them expire more slowly.Curse applies after 1 second delay Curse radius is (1.5–2.1) metres Curse duration is (6–7.4) seconds Other effects on Cursed enemies expire 25% slower Cursed enemies are Slowed by (22–28)%
Additional Effects From 1-20% Quality: +(0–10)% increased Effect of CurseSkills can be managed in the Skills Panel.PersistenceSupport, Duration Tier: 1 Cost & Reservation Multiplier: 120%Support Requirements: +5 StrSupports any skill that has a duration, making that duration longer.Supported Skills have 40% more Skill Effect DurationPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.ProfanitySupport, Chaos Tier: 1Support Requirements: +5 IntSupports Skills you use yourself. Supported Skills consume a Corpse on use, dealing more Chaos Damage if they do. Cannot support Triggered Skills or Reservation Skills.Supported Skills consume a Corpse within 5 metres on use, if possible Supported Skills deal 30% more Chaos Damage if consuming a CorpsePlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.Swift AfflictionSupport, Duration Tier: 1Support Requirements: +5 DexSupports any skill that deals damage, causing it to deal more damage over time but have a shorter duration.Supported Skills deal 30% more non-Ailment Damage over Time 20% less Duration of Supported Skills and Damaging Ailments they inflictPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.AcrimonySupport Tier: 2 Cost & Reservation Multiplier: 110%Support Requirements: +5 IntSupports Skills which can Damage Enemies. Enemies affected by Damage over time from Supported Skills which was not caused by a Damaging Ailment have reduced Life regeneration rate. Only the strongest instance of this Debuff will apply. Does not Support Skills used by Minions.Enemies affected by non-Ailment Damage over time from Supported Skills have 50% reduced Life regeneration ratePlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.HinderSupport, Spell, Chaos Tier: 2Support Requirements: +5 IntSupports Spells that deal non-AilmentChaos damage over time, causing damage over time they inflict to also Hinder enemies. Does not Support Skills used by Minions.Chaos damage over time inflicted by Supported Skills also Hinders enemiesPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.Intense AgonySupport, Spell, Duration Tier: 2Support Requirements: +5 IntSupports Spells that deal non-Ailment damage over time, causing them to have a shorter duration but deal substantially more damage over time with Debuffs inflicted against enemies on full life.Damage over time with non-AilmentDebuffs inflicted on full-life enemies by Supported Skills deal 50% more damage Supported Skills have 25% less Skill Effect DurationPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.Chaotic FreezeSupport, Spell, Chaos Tier: 3Support Requirements: +5 IntSupports Spells that deal non-AilmentChaos damage over time. Enemies taking damage over time from Debuffs caused by supported skills will suffer Freeze build up from Chaos damage Hits from any source. Does not Support Skills used by Minions.Chaos damage Contributes to Freeze buildup for Hits against targets taking damage over time from Supported SkillsPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.DerangeSupport Tier: 3Support Requirements: +5 IntSupports Skills which you use yourself which can deal damage. Supported Skills gain an Energy Shield cost equal to your Intelligence, while also dealing more non-Ailment Damage over time based off of your Intelligence. Cannot support Channelling Skills.Supported Skills gain an Energy Shield cost equal to your Intelligence Supported Skills deal 8% more non-Ailment Damage over time per 100 IntelligencePlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.Drain AilmentsSupport, Spell Tier: 3Support Requirements: +5 IntSupports Spells that deal non-Ailment damage over time, causing them to consume Ailments on enemies it applies damage over time Debuffs to in order to deal substantially more damage over time.Supported Skills Consume all Ailments of a random type on the target when inflicting damage over time Debuffs, causing the Debuff to deal 35% more damage if any Ailments were consumedPlace into a Skill's Support Gem socket in the Skills Panel to apply its effects to that Skill. You cannot have multiple copies of the same Support Gem socketed at the same time.
Essence Drain's damage over time debuff appear to be prioritized targets when casting Contagion.
Decaying Hex is linked to the curse.[1][2] This is particularly synergistic with 
Despair or 
Temporal Chains.
Persistence
Profanity
Swift Affliction
Acrimony
Hinder
Intense Agony
Chaotic Freeze
Derange
Drain Ailments
