TRICHINELLA SKIN TESTS IN AN ORPHANAGE AND PRISON. COMPARISON WITH SEROLOGIC TESTS FOR TRICHINOSIS AND WITH THE TUBERCULIN REACTION 1

Abstract

Studies were made to determine whether there is a biologic cross reaction between tuberculosis and trichinosis in human beings which is detectable by skin tests. Non-psychiatric, non-tuberculous individuals of different age groups (prisoners and orphans) were skin tested with Trichinella antigen and tuberculin. Flocculation and precipitin tests were performed on some of the subjects skin tested. 20% of the orphans gave positive Trichinella skin tests; 14% gave positive tuberculin reactions. 27.8% of the prisoners reacted positively to Trichinella antigen; 7.1% to tuberculin. No correlation was found between the tuberculin and Trichinella skin reactions. All serologic reactions in the orphans were negative. All precipitin tests in the prisoners were negative. Two of the 20 prisoners with negative Trichinella and tuberculin skin tests revealed positive flocculation reactions, though the precipitin tests on these sera were negative. The lack of correlation between skin test and serologic reaction for trichinosis suggested that the positive skin tests could not be due to recent sub-clinical epidemics of trichinosis in the institutions studied. The duration of stay in an institution appeared to be a factor in determining the incidence of positive Trichinella skin tests.