Dev Log #18 — Illness & Quarantine System

Your animals can now get sick. And if you're not careful, one sick capybara can turn into a full zoo outbreak.

🦠 Five Illness Types

Animals can now contract one of five illnesses, each with unique spread rates, cure times, and weather triggers:

Illness	Emoji	Health Drain	Cure Time	Spread (Enclosure)	Spread (Zoo-wide)
Mange	🦠	1.0/tick	90 min	10%	2%
Respiratory Infection	🫁	1.5/tick	120 min	15%	5%
Intestinal Parasites	🪱	0.5/tick	150 min	5%	1%
Fever	🌡️	1.0/tick	60 min	8%	2%
Fungal Infection	🍄	1.0/tick	100 min	18%	3%

Weather Matters

Illnesses are more likely to trigger in certain weather conditions:

Respiratory infections spread 2× faster in cold weather and during storms
Fever spikes in heat waves
Fungal infections thrive in rain (1.8× multiplier)
Mange gets worse in wet, cold conditions
Parasites love heat

Check the weather forecast and take preventive action before outbreaks start.

🏥 Quarantine

When an animal gets sick, you'll see a toast notification in the bottom-right corner. You can:

Wait it out — animals auto-cure after a set duration (60–150 minutes)
Use medicine — heal items reduce health drain but don't cure illness
Quarantine — isolate the animal to prevent spread

How Quarantine Works

Click the 🏥 Quarantine button on any sick animal
Costs $10 per hour per animal (deducted on every game tick)
Animals in quarantine cannot spread illness to others
They still auto-cure at the normal rate
Release them with the Release button once they recover

Tip: Quarantine early. One sick lion can infect your entire savanna enclosure in minutes.

💉 Immunity

After recovering from an illness, animals gain 5 days of immunity to that specific illness. They can still catch other illnesses, but they won't get the same one twice in a row.

🚨 Outbreak Detection

If more than 30% of your zoo has the same illness, the game triggers an outbreak event. You'll see it on the feed and in daily reports.

Outbreak mechanics:

Zoo-wide spread rate increases
Popularity takes a hit
Visitors complain
Your vet workers will be working overtime

Prevent outbreaks by:

Hiring vets for every enclosure
Keeping enclosures clean (>70%)
Quarantining sick animals immediately
Avoiding overcrowding

🎮 Gameplay Impact

Spread Mechanics

Every game tick, each sick animal has a chance to spread illness to:

Enclosure-mates (5–18% per tick depending on illness)
Zoo-wide (1–5% per tick — any animal in the entire zoo)

Dirty enclosures and overcrowding increase spread rates. Weather conditions multiply base spread rates (e.g., cold weather makes respiratory infections spread 2× faster).

Health Drain

Sick animals lose 0.5–1.5 health per tick. If health reaches 0, they die. Vets auto-heal animals above their threshold, but they can't cure illnesses — only prevent death.

Worker Automation

Vets will still heal sick animals to keep them alive, but they won't cure the illness
Keepers and Janitors continue working normally
Max-bot (the auto-management bot) will auto-quarantine sick animals if enabled

🧹 Prevention Tips

Keep enclosures clean — cleanliness < 50 increases spread rates
Hire vets — they keep animals above death's door
Watch the weather — quarantine proactively before storms or heat waves
Isolate fast — quarantine the first sick animal before it spreads
Don't overcrowd — full enclosures spread illness faster

🎨 UI Updates

Illness badges appear on animal cards (🦠 Mange, 🫁 Respiratory, etc.)
Quarantine button on sick animals in the Animals tab and enclosure drawers
Quarantine section in the Animals tab (filter to see all quarantined animals)
Toast notifications when an animal gets sick
Quarantine cost shown in the quarantine section ($10/hour reminder)

This system is live now. Go check your enclosures — you might already have a fungal outbreak brewing. 🍄

Stay healthy. 🦉