Sensitivity to Tuberculin, Histoplasmin and Coccidioidin Among High School Students in Northwestern Georgia

¹ The Tuberculosis Program, Division of Special Health Services, Public Health Service, U. S. Department of Health, Education and Welfare; The Dalton-Whitfield and Murray Counties Health Department, Dalton, Georgia.

A skin-testing survey with histoplasmin, coccidioidin and tuberculin, supplemented with 70 mm. chest photofluorograms, was carried out among students attending the six public high schools in Whitfield and Murray Counties, Georgia. About 90 per cent of the total estimated enrollment of 2,400 participated in the survey.

Results showed a striking reversal of the usual rural-urban pattern of prevalence of sensitivity to histoplasmin. Students living in the urban area of Dalton had a reactor rate of 55 per cent as compared with a rate of 22 per cent for those living in the rural areas. Pulmonary calcifications were found in about 12 per cent of the histoplasmin reactors. Analysis of the findings lead directly to the hypothesis that there is a source of histoplasma infection within the City of Dalton which has been present for at least several years.

About 5 per cent of the white students had reactions interpreted as positive to the 5 TU test with PPD, with only small variations around that average from school to school and between boys and girls. The rates were slightly higher for the older as compared with the younger students within the six-year age span 14 to 19 years.

Coccidioidin reactions, which were of small average size, were interpreted as nonspecific (or cross) reactions owing to histoplasma infection.