the optimal immunizing dose , 50 micrograms , induced levels of antitoxin ( geometric mean ( gm ) 302 u ) comparable to those found in eight adults convalescent from pertussis ( gm 269 u ) and greater than those found in 18-month-old children after their fourth dose of diphtheria and tetanus toxoids and pertussis vaccine ( gm 20.0 u , p less than 0.001 ) .
C0043167
pertussis
C0031237
pertussis vaccine