Infection risk is one of the Afflictions that can affect the player in The Long Dark. It is usually obtained after a fight with Wolves or a Bear. While being at risk doesn't actually do anything to the player, the condition will need to be treated before it develops into an infection.
Because this condition typically comes with Laceration, an Old Man's Beard Wound Dressing can be used to treat both conditions simultaneously. Otherwise, Antiseptic will need to be used.