A note on the incidence of rheumatic fever in Los Angeles.

Nationwide campaigns to alert the public to the dangers of rheumatic heart disease carry the hazard that parents in some localities may become more alarmed than is warranted by the local rate of incidence of the disease; and the alarm of the parent may harm the child. In such circumstances physician and patient alike might be reassured if it could be ascertained that the incidence of rheumatic fever in a given community was relatively low. Application to the Los Angeles area of a statistical formula worked out from Coombs' data on the incidence and death rate from the disease in England and from Ash's data in Philadelphia, gave indication that the incidence of rheumatic fever in all age groups in Los Angeles is approximately 68 new cases a year-a relatively favorable figure in a population approaching two million.