diff --git a/code/datums/diseases/advance/advance.dm b/code/datums/diseases/advance/advance.dm
index 57ce722cd64..bce368237ad 100644
--- a/code/datums/diseases/advance/advance.dm
+++ b/code/datums/diseases/advance/advance.dm
@@ -272,7 +272,7 @@
 /datum/disease/advance/proc/assign_properties()
 
 	if(properties?.len)
-		if(properties["stealth"] >= properties["severity"])
+		if(properties["stealth"] >= properties["severity"] && properties["severity"] > 0)
 			visibility_flags |= HIDDEN_SCANNER
 		else
 			visibility_flags &= ~HIDDEN_SCANNER