Penicillin and the marked decrease in morbidity and mortality from rheumatic fever in the United States.

There has been a marked decline in mortality due to rheumatic fever in the United States. We present evidence for the important role of penicillin in changing the severity of rheumatic carditis, beginning about 1946. Since that year, mortality due to rheumatic carditis has rapidly decreased to zero at the hospital we studied (House of the Good Samaritan, Boston), the rate of loss of all murmurs in patients at the study hospital accelerated simultaneously and exceeded 40 percent by 1970, and the rates of decline in national mortality due to rheumatic carditis accelerated fourfold with the advent of antibiotics.

Prophylaxis of streptococcal infections and rheumatic fever: a comparison of orally administered clindamycin and penicillin.

Orally administered clindamycin and penicillin were compared for effectiveness in preventing streptococcal infections in 202 randomly assigned patients with previous rheumatic fever (RF). Among 143 patients aged 21 years or younger observed for 537 patient-years, the number of streptococcal infections (and number per patient-year) was 23 (0.084) in the penicillin group and 12 (0.

Part I: abnormal patterns and physiological variations in magnetocardiograms.

Magnetocardiograms (MCGs) of six subjects with representative cardiac abnormalities and of one well-studied normal subject are compared with the 12-lead ECGs and VCGs of these subjects. The MCGs are recordings of the component of the magnetic vector which is normal to the skin, measured across the chest on a 5 cm X 5 am grid; an example is also presented of a sequence of instantaneous MCG maps. The heart abnormalities include myocardial infarction, angina pectoris, intraventricular conduction disturbances, and ventricular hypertrophy.

Dynamics in development of experimental streptococcal immunity in mice.

The interrelation between the humoral and cellular factors in the development of immunity to experimental streptococcal infection was investigated. Early resistance to infection was caused by stimulating the phagocytic cells to function efficiently in the absence of opsonins. Subsequently, the appearance of cytophilic antibodies provided further means for elimination of streptococci.

Secondary and apparent primary antibody responses after group A streptococcal vaccination of 21 children.

A partially purified M protein, extracted from a mouse-virulent strain of type 3, group A streptococcus, was administered subcutaneously in gradually increasing amounts at weekly intervals to 21 children in a Family Program. Seven children with type 3 bactericidal antibody in prevaccination sera showed a secondary response. Of 14 children with no detectable type 3 bactericidal antibody prior to vaccination, 13 developed definite type 3 antibody during or soon after vaccination.

Preferential inhibition of penicillinase induction by oxytetracycline and its effect on the penicillin susceptibility of staphylococci.

Exposure of penicillinase-producing staphylococci to a combination of penicillin and oxytetracycline resulted in a synergistic inhibitory activity of the antibiotics on the bacteria. Oxytetracycline was employed in concentrations having little or no effect on bacterial growth. It was found that the synergistic antibacterial effect was caused by the preferential inhibition of penicillinase induction by oxytetracycline, rendering the staphylococci more susceptible to penicillin.

EFFECT OF SUBLETHAL CONCENTRATIONS OF PENICILLIN ON THE VIRULENCE AND ANTIGENIC COMPOSITION OF GROUP A STREPTOCOCCI.

Michael, J. Gabriel (House of the Good Samaritan, Children's Hospital Medical Center, Boston, Mass.), Benedict F.