Dr. R. Palmer Beasley was a physician, epidemiologist, and public health educator from the U.S. In 1972, Beasley visited Taiwan for the second time and conducted hepatitis B research. In 1975, vertical transmission between mother and infant was proven. While in 1981, Beasley showed that there existed a causal relationship between hepatitis and liver cancer. With the team consisting of Dr. Hwang Lu-Yu, Pediatrics, National Taiwan University Hospital; Prof. Lin Jia-Chin of National Taiwan University College of Public Health; postgraduate students Chen Chien-Jen, Twu Shiing-Jer; and Dr. Chang Mei-Hwei, Pediatrics, National Taiwan University Hospital; Beasley assisted in the pediatric screening for hepatitis and proved that the hepatitis B vaccine is able to effectively disrupt vertical transmission. A vaccine program was launched in 1984, and the country saw a significant decrease in newborn children carriers.