SINCE IT has been demonstrated that live rubeola and polio vaccines can suppress the tuberculin skin test, converting a positive reaction into a negative one,1,2 it was thought worthwhile to determine whether live rubella vaccine exerted a similar effect. Seven tuberculin-positive children were considered to be susceptible to rubella on the basis of having no hemagglutination-inhibiting (HI) antibodies. Nonspecific serum inhibitors were removed by the heparin-manganese chloride method.3 Each child received 0.5 ml of HPV-80 rubella vaccine, and all responded serologically. Virus was recovered from three of the children. Four children had decreases in the sizes of their tuberculin reactions (intermediate strength purified protein derivative [PPD]), 3 to less than 10 mm in diameter (Fig 1 and 2). The skin test in the other three remained unchanged. No deleterious effects were noted in the six children with active, primary, pulmonary tuberculosis who received the vaccine. Additional studies will