Project Zomboid Infection Settings (Build 42.19): Turn Off Knox, Modes Explained
Build 42.19 · Sandbox Zombie Lore: Transmission, Infection Mortality, and what Antibiotics actually do
- Everyone’s Infected does not mean bites and scratches stop spreading Knox. It means the world treats everyone as carriers: death can turn you even without a “fresh” wound infection story, while attack infection still applies under current rules.
- Setting both Transmission and Mortality is not required to “turn infection off.” Use None alone to block new spread.
- Antibiotics fight ordinary wound infections. They cannot prevent zombification (item tooltip).
Two different “infections”
Knox virus (zombie plague)
Controlled by sandbox Zombie Lore: Transmission and Infection Mortality. Default Apocalypse-style pace uses multi-day virus mortality after infection. There is no vanilla cure once you are truly on the Knox path.
Under default-style transmission, bite wounds are treated as a near-certain Knox risk; scratches and lacerations are lower-chance routes. See the bite / turn timeline guide for symptom pacing—not every Queasy moodle means Knox.
Ordinary illness
Dirty wounds, food poisoning, corpse smell sickness, and similar effects are separate systems. They can still kill you through fever and health loss, but they are not the same flag as Knox zombification.
Medical care, rest, clean water, and (for septic wounds) items like Antibiotics matter here. Sandbox Transmission does not switch those off.
Transmission modes (Build 42.19)
UI path: custom sandbox or server sandbox → Zombie Lore → Transmission.
Server file field: ZombieLore.Transmission (values start at 1). Official English labels:
| UI label | File value | What it means for players |
|---|---|---|
| Blood and Saliva | 1 |
Default-style Knox spread through blood and saliva contact routes (common preset default). |
| Saliva Only | 2 |
Stricter path focused on saliva (typically bite-focused vs broader blood routes). Use when you want fewer “scratch ruined the run” outcomes without full immunity. |
| Everyone’s Infected | 3 |
Not “attacks cannot infect.” Everyone is already a carrier in lore terms: reanimation after death is the headline effect. Zombie attacks can still put you on the infection path. Do not pick this if your goal is bite-safe play. |
| None | 4 |
Stops new Knox infection from zombie attacks. This is the real “turn infection off” switch for new bites/scratches/lacerations. |
Infection Mortality (separate from Transmission)
UI label: Infection Mortality (“How quickly the infection takes effect.”).
Server file field: ZombieLore.Mortality — not a separate top-level key with the UI name.
Apocalypse preset uses value 5 (2-3 Days).
| UI label | File value | Role |
|---|---|---|
| Instant | 1 |
Virus kills immediately once infection applies. |
| 0-30 Seconds | 2 |
Very short timer. |
| 0-1 Minutes | 3 |
Short timer. |
| 0-12 Hours | 4 |
Same-day timer. |
| 2-3 Days | 5 |
Multi-day timer (typical default-style pace). |
| 1-2 Weeks | 6 |
Long timer. |
| Never | 7 |
Virus timer never kills. Does not block new infections by itself. |
How to disable Knox spread
Single-player custom sandbox
- Create a new game with Custom Sandbox.
- Open Zombie Lore.
- Set Transmission to None.
- Leave Infection Mortality alone unless you also want Never on the death timer.
- Start the world. Mid-save sandbox edits are limited compared with a dedicated server file—plan this before a long single-player run when possible.
Host / dedicated server
- Stop the server cleanly and back up the profile (at least
<ServerName>.iniand<ServerName>_SandboxVars.lua). - Prefer Host / manage settings UI → Sandbox → Zombie Lore → Transmission = None.
- Or edit the sandbox file under the running user’s home:
- Windows:
C:\Users\<Username>\Zomboid\Server\<ServerName>_SandboxVars.lua - macOS / Linux:
~/Zomboid/Server/<ServerName>_SandboxVars.lua
- Windows:
- Inside
ZombieLore = { … }, setTransmission = 4. OptionallyMortality = 7. - Start the server again so clients load the new values.
-- Inside <ServerName>_SandboxVars.lua (other fields omitted)
ZombieLore = {
Transmission = 4, -- None: no new Knox from zombie attacks
Mortality = 5, -- keep default-style 2-3 Days, or set 7 for Never
},ZombieLore.Mortality. A top-level InfectionMortality = 7 will not apply.
Step-by-step multiplayer paths and platform notes: Turn off infection (Transmission = None).
Wound infection, food sickness, antibiotics
Wound infection (not Knox)
- Dirty or poorly managed wounds can become septic (health panel “infected wound” style status).
- Antibiotics reduce wound infection power. Tooltip: Fights wound infections. Cannot prevent zombification.
- Disinfect, bandage, rest, and First Aid skill still matter. Do not treat Antibiotics as a Knox cure.
Food / environment sickness
- Rotten food, tainted water, and heavy corpse exposure can make you Queasy or worse without any zombie bite.
- Sandbox food spoil rates and hygiene habits reduce these deaths; they are unrelated to Transmission.
- Trust the health panel and moodles in your current build rather than old version rumors about food sickness strength.
Debug emergency clear (already bitten)
Changing sandbox Transmission does not always clear a character who is already infected. For a local emergency save, debug tools can clear the Knox flag.
- Steam → Project Zomboid → Properties → Launch Options: add
-debug. - Load the save. Open the debug menu (bug icon / debug toolstrip).
- Open General → stats / body tools.
- Uncheck Infected. You can also adjust the Zombie Infection slider if present.
- God Mode is a separate invulnerability toggle—not required just to clear infection. Prefer the explicit Infected flag when you only need to undo Knox.
Mods (verify yourself)
Workshop mods can add immunity, probabilistic recovery, amputation, or crafted cures. Names change, and forks often lag behind Build 42.
- Search Steam Workshop for current Build 42 tags and recent update notes before installing.
- Note Workshop ID, load order, and whether the mod edits infection chance, mortality, or only post-infection recovery.
- Prefer sandbox Transmission = None for a clean vanilla-compatible “no Knox spread” multiplayer baseline; use mods only when you want partial risk or roleplay cures.
- Common categories people look for: immune traits, antibody systems, rare cure items, amputation kits, configurable infection thresholds, general cheat menus. Confirm each mod’s update status yourself.
FAQ
Do I need Transmission = None and Mortality = Never together?
No. None alone stops new attack infection. Never only removes the virus death timer for people who are already infected (or who become infected under other modes).
Is Everyone’s Infected the soft multiplayer mode?
No. It is the “everyone carries it / death can turn you” lore mode. Soft multiplayer for bites is Transmission = None (or careful Saliva Only if you still want some risk).
Can antibiotics or Lemongrass cure Knox?
No. Antibiotics target wound infection power and explicitly cannot prevent zombification. Herbs and food recovery help ordinary sickness, not the Knox flag.
Does Transmission = None make me invincible?
No. Bleeding, fractures, exhaustion, fires, vehicles, and swarms still end runs. Only the Knox infection channel from attacks is closed.
What about an existing infected character after I change sandbox?
Changing Transmission does not always erase a live infection clock. Use debug Infected toggles on a backup, set Mortality = Never as a softer world rule, or accept a new character. Plan world rules before long co-op seasons when you can.
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