Blood transfusion
Blood transfusion, transfusion of blood products, or organ transplants without HCV screening carry significant risks of infection. The United States instituted universal screening in 1992 and Canada instituted universal screening in 1990. This decreased the risk from one in 200 units to between one in 10,000 to one in 10,000,000 per unit of blood. This low risk remains as there is a period of about 11–70 days between the potential blood donor's acquiring and the blood's testing positive depending on the method. Some countries do not screen for due to the cost.