COCCIDIOIDIN, HISTOPLASMIN, AND TUBERCULIN SENSITIVITY AMONG SCHOOL CHILDREN IN MARICOPA COUNTY, ARIZONA

Doto, I. L., F. E. Tosh (Ecological Investigations Program, CDC, Kansas City, Kansas 66103), S. F. Farnsworth and M. L. Furcolow. Coccidioidin, histoplasmin, and tuberculin sensitivity among school children in Maricopa County, Arizona. Am J Epidemiol 95: 464–474, 1972.—Children from 32 schools in Maricopa County, Arizona, were tested for cutaneous sensitivity to coccidioidin, histoplasmin, and tuberculin antigens. Approximately one-third of all children tested had a positive coccidioidin skin test. The frequency of positive coccidioidin skin tests was 60% among Indian children, 42% among Spanish-American children, and 32 and 30% among Negro and white children. The frequency of positive reactions to coccidioidin was higher among residents of rural areas than residents of urban areas. Estimated annual conversion rates ranged from 3.2% in central Phoenix to 10.7% in the southwest part of the county. Approximately 15% of the children tested had a positive histoplasmin skin test, but the majority of these individuals had a positive coccidioidin skin test that was larger than the histoplasmin, suggesting cross reaction. However, 2.7% of the children had a positive histoplasmin skin test in the absence of a positive coccidioidin test, indicating a low level of infection with Histoplasma capsulatum for residents of the county. The prevalence of sensitivity to tuberculin was 2.4%. Positive tuberculin tests were 2 to 3 times as frequent among Spanish-American and Indian children as among white and Negro children.