AN EXPERIMENTAL APPROACH TO THE PROBLEM OF ACQUIRED IMMUNITY IN HUMAN HOOKWORM (NECATOR AMERICANUS) INFECTIONS1

Abstract

Infective larvae of N. americanus were placed in sera collected from 23 white and colored children harboring varying intensities of infection and from 5 white children who had never been exposed to hookworm infection. A precipitin reaction was obtained in and around the oral, anal and genital openings of some of the larvae placed in the sera of 8 out of 14 children with very light, light and moderate infections, and of 3 uninfected children from infected families; no precipitin reaction was obtained in the sera of 6 children harboring heavy and very heavy infections, and of the 6 uninfected unexposed children. The data suggest that the precipitin reaction may be specific and play a role in the development of acquired immunity against hookworm infection.