While saving a merchant who had been burying the dead from the war of Nilfgaard, Geralt was bitten by a ghoul. The poison from such a bite would have killed any human, but Witchers have a greater resistance to poisons. However, it still plunges Geralt into illness, left at the mercy of the elements until a kind stranger comes to his aid. Being as reserved and untrustful as he is, he doesn't trust them at first but realizes he has no choice but to let them care for him if he wants to survive. 