Qui-Lim Choo is a Singapore-born scientist, who along with Michael Houghton, George Kuo and Daniel W. Bradley, co-discovered and cloned Hepatitis C in 1989. He also co-discovered the Hepatitis D genome in 1986. The discovery of Hepatitis C led to the rapid development of diagnostic reagents to detect Hepatitis C virus in blood supplies which has reduced the risk of acquiring hepatitis C through blood transfusion from one in three to about one in two million. It is estimated that antibody testing has prevented at least 40,000 new infections per year in the US alone and many more worldwide.