Questionable Value of Skin Testing as a Means of Establishing an Epidemiological Index of Tuberculous Infection

The Significance of Unstable Tuberculin Reactions

“…4) It is suggested that reactors with a low degree of sensitivity to tuberculin be retested at intervals and that a marked increase in sensitivity be investigated by chest roentgenogram. RESUMEN 1) Se revisan los hallazgos obtenidos de un programa de pruebas tuberculinicas entre los estudiantes de medicina.…”

“…4) Se sugiere que los reactores con bajo grado de sensibilidad a la tuberculina sean vueltos a probar con intervalos y que un aumento de la tuberculino sensibilidad sea investigada mediante radiografias del t6rax.…”

Frost Revisited: The Modern Epidemiology of Tuberculosis

“…The iconoclast was Dr. L. L. Lumsden, a friend of Frost's and one of the Public Health Service's outstanding shoe-leather epidemiologists (6). Lumsden not only made the same observation about the nonconcordance of tuberculin reactions and pulmonary calcifications, but found that different tuberculin preparations, especially the stronger doses, gave discrepant results (7). He came to the conclusion that the tuberculin test was worthless and said so plainly.…”