Day 8+ Advanced Symptoms

Master laboratory mechanics and unlock hidden symptoms to survive the late game

Last Updated: January 19, 2026

The Late-Game Challenge

Day 7-8 marks a major turning point in Quarantine Zone. The Laboratory opens, revealing symptoms that were previously invisible to you. Without discovering these hidden symptoms, you'll miss infections and lose survivors. This guide covers everything you need to master late-game detection.

What Changes at Day 7-8

Laboratory Access

Discover hidden symptoms by extracting infected organs from suspects

Contraband Inspection

Must now check backpacks for weapons, drugs, and contaminated body parts

Bulletin Board Requests

Special missions appear that add complexity to your decisions

More Symptom Combinations

Survivors start showing multiple symptoms across different tools

Tool Unlock Timeline

Each tool unlocks on specific days. Know what you can detect and when.

Day 1-2Visual inspection only (appearance symptoms)
Day 2Thermo-Pulse-Meter (temperature, pulse)
Day 3-4Hammer (reflex testing)
Day 5-6Scanner (see through clothes), Stethoscope
Day 7-8Laboratory access, Contraband checking
Day 9+X-Ray (internal organs)
Day 11+Matioscope (eye organisms)
Day 13+UV Tower (hidden symptoms)
Day 17-18All equipment unlocked - endgame begins

Symptoms Requiring Laboratory Discovery

These symptoms are INVISIBLE until you discover them in the Laboratory. Send survivors with unknown symptoms to the lab to unlock detection.

Appearance

HerpesSafe

Rash-like misshapen splotches, brown/red, no zits

Skin RashQuarantine

Rash full of zits and whiteheads with small splotches

Mouth BleedingQuarantine

Blood on lower lip running toward chin

Eye PusLiquidate

Small green pus drop on corner of eye (very hard to see)

Nose PusLiquidate

Green pus dripping from nostril

Stethoscope

Nonspecific RespirationQuarantine

Wheeze during BOTH inhale AND exhale

Infected BreathLiquidate

Zombie growling instead of breathing sounds

X-Ray

Fatty HepatosisSafe

Yellow splotches on organ (ignore pancreas)

Color DifferencesQuarantine

Purple or pinkish organ color

Moldy OrganLiquidate

Teal blue colored organ

Organ NecrosisLiquidate

Dark black splotches on organ

Behavioral Cues

Watch for these behaviors to know where to look for symptoms:

BehaviorCheck Area
Dropped jaw / slack mouthUse Hammer - reflex symptoms
Grabbing stomachUse X-Ray - organ symptoms
Coughing / sneezing / hiccuppingUse Thermopulsometer or Stethoscope
Droopy / half-closed eyesUse Matioscope - eye organisms

Critical Distinctions

Don't confuse these similar-looking symptoms:

Bruises vs Red Bruise vs Necrosis

Safe

Bruises: Blue-green-yellow mix

Quarantine

Red Bruise: Dark red splotches

Liquidate

Necrosis: Black splotches (not tattoos!)

Eye Conditions

Safe

Yellow Eyes: Yellow-tinted whites

Quarantine

Conjunctivitis: Red corners only

Liquidate

Red Eyes: Entirely bright red whites

Breathing Sounds

Safe

Sickly Breath: Wheeze on inhale only

Quarantine

Nonspecific: Wheeze on both inhale AND exhale

Liquidate

Infected: Zombie growling sound

Advanced Detection Tips

Temperature Timing

Temperature takes 5-7 seconds to stabilize. The initial reading is WRONG - wait for it to stop rising!

Green Skin Looks Yellow

Despite the name, 'Green Skin' actually appears yellow like a Simpson character. Compare with ID photo (Tab).

Don't Mistake Tattoos

Black tattoos can look like Necrosis. Look for artistic patterns, faces, symbols, or words.

Matioscope Shape > Color

Eye organisms may appear in different colors than the symptom list shows. Focus on their SHAPE, not color.

Hidden Symptom Locations

Check backs, under arms, feet, and behind clothing. Use the Scanner to see through clothes.

UV-Only Symptoms

Some bites, necrosis, and pus are INVISIBLE normally. Always use UV Tower to reveal hidden red symptoms.

Symptom Scanner (Late-Game Upgrade)

Upgrade your entrance scanner to detect symptom categories. If a symbol lights up, check that tool. If it doesn't light up, skip that check entirely.

Scanner can rarely have false negatives. Trust it 99% of the time, but stay alert.

Related Guides