Summary

The incidence of skin sensitivity to histoplasmin, tuberculin, and blastomycin in a population of 447 Liberians, predominately working males, was found to be 15.4%, 80.8% and 1.6% respectively.

There was no evidence for cross reaction between any of the antigens used.

Of the histoplasmin reactors 70% were followed by chest x-rays. Of 48 chest films examined only 11 showed pulmonary lesions, and only 9 (18.8%) of these consisted of calcifications. All but one of the positive x-rays were of subjects who were also tuberculin positive, and none of the lesions seen was absolutely typical of histoplasmosis.