purified acellular pertussis vaccine ( 12.5 micrograms of lymphocytosis promoting factor [ lpf ] and 12.5 micrograms of filamentous hemagglutinin [ fha ] ) was compared with conventional pertussis vaccine in a randomized double-blind study involving 40 children aged 4-6 y , 40 children aged 18-24 mo , and 50 infants .
C0008059
children
C0021270
infants