Mr. K.S. has sustained a ruptured spleen following a fall from his cottage roof. He has a hemogolobin of 60 g/L and you recommend a blood transfusion. The patient informs you that he is worried about contracting HIV from the blood product and doesn’t want to leave the hospital sicker than he was when he got there. What everyday risk would you liken the probability of acquiring HIV from a blood product to so that Mr. K.S. can best understand?