[Effects Of Irradiation With Cobalt 60 To The Development Of Ascaris Eggs In Stool]

This study was carried out in order to find out the valuable measure to kill the parasite eggs in night soil. The fresh eggs of Ascaris put into human stool were irradiated with Cobalt 60 of 200,000 to 1,000,000 rad and cultured in test tubes at 25-30 degrees C, washing with 2 % formalin solution every 24 hours. The continuous development of those eggs were observed under microscope and the proprotions of developed eggs were compared with those of control groups. The major result can be summarized as follows: 1)In general, The eggs in stool developed poorly than the eggs in saline. 2)If the eggs were irradiated with the larger dose of Cobalt 60, the proportion of developed eggs were reduced subsequently. 3)The eggs irradiated with the dose of 1,000,000 rad in saline developed in the proportion of 15.5 %, whereas irradiated with 200,000 rad 94 % developed in 4 weeks. 4)The 44.5 % of eggs in stool irradiated with 200,000 rad developed after 4 weeks, 30.5 % with 300,000 rad, 25 % with 500,000 rad and 3.5 % with 1,000,000 rad respectively. 5)The effective minimum dose of Cobalt 60 irradiation to kill the Ascaris eggs in stool was estimated 1,000,000 rad. Further examination will be required to observe the infectivity of irradiated Ascaris eggs to animals and to evaluate the effect from the standpoint of sanitary engineerings.

[Immuno-Diffusion And Complement-Fixation Test In Paragonimiasis Of Cat]

In order to observe the complement fixation test and immuno-diffusion test of paragonimiasis, the sera taken at 10 days intervals up to 150 days from cats infected with Paragonimus westermani were examined by the above two immunological methods. The resultant findings were as follows: 1)The complement fixation test showed positive reaction 20 days after the infection with 20 metacercariae, and 40~50 days after the infection with 10 metacercariae. The highest titer was observed 110 days later following the acceleration at 80 days later. 2)In immuno-diffusion test, one are appeared 30 days after the infection with 20 metacercariae, but 60 days after the infection with 10 metacercariae. However, more than two arcs were observed since 70 days after infection. 3)A relatively wide band appeared by the antigens of Fresh worm material and Somatic material. But relatively clear precipitin lines were observed in the diffusion test with V.B.S. antigen, increasing to 3~4 arcs after 110days. 4)In general, complement fixation test showed earlier and higher sensitive reaction than immuno-diffusion test, and was considered to be more valuable method forr immunological diagnosis.