How to Turn Off Infection in Project Zomboid
How to Turn Off Infection in Project Zomboid
🎯 One-Sentence Snapshot
You can turn off infection in Project Zomboid B41/B42 by tweaking sandbox Zombie Lore settings (set Transmission to None and Infection Mortality to Never), or by using mods/cheats to cure or disable both the lethal Knox virus and regular wound/food infections.
📋 Table of Contents
Understanding Infections in Project Zomboid
In Project Zomboid, "infection" can mean two very different things:
The Knox Event Virus
The zombie plague that turns you undead after a bite/scratch. This is lethal by default and the main focus of infection settings.
Regular Infections & Illnesses
Everyday health threats like infected wounds, food poisoning, dysentery, etc., which can sicken but aren't the zombie virus.
1. The Zombie Virus ("Knox Infection")
The Knox Infection is the lethal virus spread by zombie attacks. By default, if a zombie bites you, it's a guaranteed game over (100% fatal). Lacerations and scratches can also transmit the virus, but with a chance. In Build 41+, the probabilities are about 7% for scratches and 25% for lacerations.
Once infected, you'll see the telltale Queasy/Agitated moodles, fever, and declining health over ~2-3 days until death. There is no cure in vanilla; the devs intend it as an inevitability.
Default infection chances:
- Zombie Bite: 100% infection rate
- Laceration: 25% infection rate
- Scratch: 7% infection rate
2. Regular Infections & Illnesses
Apart from the zombie virus, your survivor can get "ordinary" infections and diseases:
Wound Infections
Leaving a wound dirty or untreated can cause septicemia. Treatable with disinfectant or antibiotics (added in B42). Learn more in our first aid guide.
Food Poisoning
Eating rotten food or drinking tainted water causes sickness. B42 made this less lethal than in B41. See our fever treatment guide for recovery tips.
Corpse Sickness
Being around rotting zombie bodies without protection causes nasty sickness. Rest and food help recovery.
Sandbox/Mod Diseases
Some mods add diseases like dysentery, cholera, etc. Not part of vanilla B41/B42 but worth considering.
Understanding this difference is key because turning off "infection" in sandbox only refers to the zombie infection by default. The game doesn't have a single master switch to turn off all illnesses.
Permanent Solutions: Disabling Zombie Virus Infection
Let's start with the big one: zombification. If you want to permanently disable the zombie virus (so bites/scratches no longer kill you or turn you), the game provides sandbox options to do so.
Sandbox Settings Method (No Mods Required)
The simplest way to turn off the zombie infection is using the Custom Sandbox settings when you start a new game (or in server settings for multiplayer). Under the Zombie Lore section, there are two critical parameters:
Transmission
Controls how the virus spreads (bite, blood, etc.). Set to "None" to disable transmission.
Infection Mortality
Controls how deadly the virus is and how quickly it kills. Set to "Never" to ensure survival.
Sandbox "Zombie Lore" options in Project Zomboid. In this example, Transmission is set to None and Infection Mortality to Never, effectively turning off the zombie virus threat.
💡 Tip: Another preset option is "Everyone's Infected" mode. In sandbox this is Transmission = Everyone's Infected, which mirrors The Walking Dead style lore. In that mode, everyone already has the virus, so bites don't cause zombification (no additional infection to catch). You only turn if you die from any cause. This can be particularly useful during events like the helicopter event where bites are more likely.
Editing Config Files (Server & Advanced Users)
Transmission = 4,
InfectionMortality = 7,This configuration completely disables zombie infection on your server or saved game. For more server administration tips, check our server admin guide.
- Transmission uses:
1= Blood+Saliva,2= Saliva Only,3= Everyone's Infected,4= None. - InfectionMortality uses:
1= Instant,2= 0-30 sec,3= 0-1 min,4= 0-12 hours,5= 2-3 days,6= 1-2 weeks,7= Never.
Trade-offs & Gameplay Impact
Be aware that removing zombification does change the game's balance. It makes Project Zomboid significantly easier in some ways – you no longer fear any single bite ending your run. However, without the zombie virus threat, the game loses some tension.
✅ Benefits
- Great for co-op where one bite shouldn't end a player's run
- Better for long-term base building projects
- Less frustration from one small mistake ending everything
- Focus more on survival mechanics than "don't get scratched ever"
⚠️ Drawbacks
- Removes a major source of tension and challenge
- Makes combat less risky - you can take more chances
- Less authentic to the "zombie apocalypse" experience
- Can make the game feel significantly easier
Alternative Approaches
- Bite only infection - Set Transmission: Saliva Only so scratches/lacerations won't infect
- Lower infection chance - Use mods that let you tweak infection odds
- "Cure" mechanics - Keep infection on, but add gameplay around finding a cure
Mod-Based Solutions and Cheats
What if you're already mid-game and got bitten? Or maybe you do want infection on, but with a chance to cure it? Here are mod-based solutions and other methods.
Top Mods to Disable or Cure Zombie Infection
Disabling Regular Infections & Diseases
The base game doesn't have explicit toggles for regular infections, but here are ways to effectively remove or mitigate them:
🩹 Wound Infections
Set Basic Injury Severity lower in sandbox. Always boil bandages, disinfect wounds, and use antibiotics in B42.
🍗 Food Poisoning
Turn Food Spoilage to "very slow" or turn Rotten Food Removal on. Use Lemongrass (foraged herb) to treat food poisoning.
Debug Mode & Cheat Menu
If your character has been bitten and is fading fast, you can rescue them via debug/cheats:
Enable Debug Mode - On Steam, right-click Project Zomboid > Properties > in Launch Options type -debug
In-game, click the debug icon (bug icon) at the bottom-right
Go to General Debuggers > Player or Health and enable God Mode
This will instantly cure all infections. Turn off God Mode afterward to continue playing normally.
Note: Using debug mode marks your save as "cheated" (no achievements). Always keep backup saves when using debug mode.
Build 41 vs Build 42 – Infection Changes
Build 42 (as of early 2025) introduced some tweaks to infection mechanics: