This is a study conducted in regard to the 299 persons who visited the clinics as out-patients or those who were subjected to the mass examination and were found as a result of stool examination to be hookworm infection cases-all of them found in the. rural area in the vicinity of Anan-machi, Ina-gun, Nagano Prefecture.Measurement of haemoglobin, red-cell count, direct eosinophil count, reticulocyte count, total serum-protein, serum-iron and serum-copper, and Gluferricon load test were executed.Results of study of the blood pictures thus obtained before and during anthelmintic treatment (with or without iron administration) are summarized as follows:
1. Hookworm infection caused iron deficiency anemia, accompanied with eosinophilia. Reticulocyte count showed a marked increase in hookworm carriers.
2. The minimum number of parasites that produced anemia was about 30 for the male patients and about 20 for the femle patients.
3. Serum-iron decreased whereas serum-copper remained normal in the present cases of anemia.
4.By Gluferricon load test, increase in “Decrease” and “ Decrease-increase ratio” was observed in some of hookworm carriers. It was conspicuous in anemic cases.
5. Increase of haemoglobin per diem by oral administration of iron was 1.09% before the execution of anthelmintic treatment and 1.815% after it;only by anthelmintic treatment, it was as low as 0.1%.
6. In the very heavily infected cases (with more than 60 worms), oral administration. of iron was ineffective.
7.Anthelmintic treatment alone was found effective for recovering haemoglobin value almost to normal in one year's time.
