The cutaneous infections in human host with the infective larvae of Ancylostoma duodenale and Necator americanus were carried out in many volunteers in order to determine the infection mode of hookworm. The results were as follows.
1. In Necator americanus cases the rate of number of worms expelled by anthelmintic treatment to number of larvae penetrated into the skin was 13.1% and the corrected rate was 13.5%.
2. In Ancylostoma duodenale cases the rates mentioned above were 3.8% and 4.1% respectively.
3. From the results mentioned above the authors consider that Necator americanus can more easily infect in human host percutaneously than Ancylostoma duodenale.