다슬기(Semisulcospira libertina)棲息處의 水質에 關한 硏究

Abstract

[한글]

[영문]

Paragonimiasis has been recognized as a major public health problem in various parts of the Far East (Sandan, 1960), but apparently it is more prevailing in Korea than in any other country in the world (Kobayashi; 1919; 1921). According to the

references, several clinical studies and field surveys on paragonimiasis and its intermediate hosts have been carried out since Mooda(1919; 1913) published his report "Extrapulmonary Paragonimiasis in Hai-Joo-Guhn, Whang-Hai-Do" in 1912 and 1913.

His report that approximately 8 percent of 350,000 Koreans examined were positive for this fluke prompted his conclusion that paragomimasis is one of the most important diseases in Korea (Kobeyashi, 1926).

However, most of the past studies on paragenimiasis were meinly concerned with adults, but rarely with children, Miller and Walker(1955) studied 227 infected pirsoners of war from a roentgenographic stand-point in an attempt to delineate the

radiographic features of this desease, in order to differentiate it from pulmonary tuberculosis. Graumann et al. (1957) emphasized the clinical and public health importance of paragonimiasis in Korean and indicated that a large number of individuals have extrapulmonary infections. Sadun and Buck (1960) have recently

done comprehensive studies on paragonimiasis insouth Korea, including immuno-diagnostic, epidemiologic, clinical, Reentgenelogic and therapeutic studies.

According to a recent survey (Nalotn & Chyu, 1959), (Sadun et al. 1960), it is estimated that over a quarter million human infections occur in South Korea and Approximately one million persons are infected in Japan.

However, studies of the water analysis of the breeding places of the first intermendiate host (Semisulcospire Libertina) have not been carried out. The breeding places of Semisuleospira Libertina in the Haenan area were found mainly in pebbly and sandy riverbed of the upper stream and halfway up the Dong-Hoe river, but we could not find the habitats of Semisulcospira libertina in the spring, paddyfield and tidal part of flow in which the content of Cl ion, Ca ion, total alkalinity, total hardness and pH were obviously higher than those of the breeding

places.

The ranges of physical and chemical characters of the Semisulcospira libertima breading water were as follows; 0.05-0.7 m/sec. of optimal flowing velocity of fresh water, 20-50 cm in deepth, 7.12±0.17 of optimal pH range, 19.4±4.92(mg/l) in total alkalinity, 9.4±2.97(mg/l) of Ca ion, 9.8±2.3(mg/l) of Cl ion content, 115.1±34.2(mg/l) of total hardness, but there were no remarkable differences between the habitat water and the contrasts in their specific gravities.

In the comparison of the analytical results of the breeding water at Haenan, the content of Ca ion, Cl ion, total alkelinity, total hardness and pH showed a gradually higher value in the lower reaches of the river than those of the upper stream and halfway up the river.