Necator americanus and Ancylostoma duodenale in Guam, Leyte, and Okinawa, with a Note on Hookworm Egg Sizes

During the course of parasitological studies of natives and service personnel on Guam, M. I., in 1945, some hookworm counts after treatment were included to determine the species involved. In addition, worms from necropsies of natives of Guam and Okinawa became available for examination. While a more definitive statement would need to be based on a larger number than the 4056 hookworms reported upon, the consistency of the findings permits a provisional species index for Guam, Leyte and Okinawa. Advantage was also taken of the presence of pure and mixed infections of Necator americanus and Ancylostomca duodenale to test whether egg measurements at fecal diagnosis could be used to reliably indicate the presence of a particular species. Some of the hookworms here classified were collected following treatment of Guamanians at the United States Naval Military Government Hospital No. 203 (Agana), and of service men in the wards of the Naval Medical Research Unit No. 2; others were obtained at necropsies performed on natives of Guam at the Agana Hospital by Commander H. M. Zimmerman, MC(S), USNR. Those from necropsies of Okinawans were examined through the cooperation of Commanders E. L. Benjamin, MC(S), USNR, and Zimmerman, and Lieutenant Commanders M. B. Franks, MC(S), USNR and Harold Fink, MC, USNR. Acknowledgment is made to these officers, as well as to the physicians and nurses of the pediatrics ward of the Agana Hospital, and to the medical officers and pharmacists' mates of NAMRU No. 2, who made the post-treatment collections effective. Identification of all hookworms was made by the writer. It will be noted that no specimens of A. braziliense were encountered, although there are occasional references to it as a human parasite in this part of the world. Hookworms from Guamanian dogs all proved to be A. caninum.