EPIDEMIOLOGIC STUDIES OF Q FEVER IN SOUTHERN CALIFORNIA

Abstract

When Q fever was discovered in the metropolitan area of Los Angeles in 1947, extensive epidemiologic studies were undertaken to determine the source of human infection and disease. The studies were carried out by the National Institutes of Health in cooperation with the California State Departments of Public Health and Agriculture and the Los Angeles city and county health departments. More than 12,000 persons have been studied, and a detailed report will be published at a later date. The present report is a summary of the important epidemiologic findings which indicate that local dairy cows and their raw products, particularly milk, were the most frequent sources of human infection and that these infections have caused many persons to have an illness not heretofore recognized as Q fever. Q fever was first described by Derrick in 1937. The disease is now generally recognized as an acute illness caused by a rickettsia,