Insecticide resistance in bedbugs(Cimex lectularius) in Korea

In the summer of 1969 from July through October, authors carried out a study of susceptibility in adult female bed bug(Cimex lectularius) in order to ascertain any development of resistance to insecticides in Korea. The test to DDT and Dieldrin was performed in laboratory by the continuous exposure of residues method, with standard impregnated paper used for adult mosqitoes. Some results so far obtained can be summarised as follows: LC(50) were 2.839% in DDT and 0.167% in Dieldrin. The resistance has been arisen 2.4-2.9 times in DDT and 1.6-2.4 times in Dieldrin as compared with London laboratory strain, but they were susceptible 1.4 times in DDT and 180 times in Dieldrin as compared to Israel resistance strain.

Parasitological studies of Korean forces in South Vietnam I. Examination of blood films on malaria patients

A parasitological study was performed with 452 malaria patients evacuated from South Vietnam by examinations of their peripheral blood. Results were as follows: The peripheral blood examinations revealed that 52.0% of the examined have parasitemia, of which 95.3% was P. falciparum, one case of P. vivax and the other 10 patients were mixed infected. Neither P. malaria nor P. ovale were found. A total of 1,500 thick and thin blood films was prepared and 707 slides of them (47.1%) showed positive. In P. falciparum, ring forms were found most frequently and the next was gametocytes. Eighty slides (50%) showed mixed together with both ring form and gametocytes. All of the erythrocytic stages were seen in three slides of P. vivax. Weekly periodical examinations showed 233.8 parasite density every 1,000 W.B.C count in average, while occasional at fever attacks 531.7.Size of gametocytes in P. falciparum was 9.31(+/-0.89) by 2.16(+/-0.53) in macrogametocyte and 6.61(+/-0.82) by 2.51(+/-0.35) in microgametocyte. Their sex ratio was 100 : 92. Repeated blood examinations showed increased detection rates. The positive rate of parasitemia was 52.0% in single examination, increasing in succession with repetitions.

Parasitologial studies of Korean Forces in South Vietnam II. A comparative study on the incidences of intestinal parasites

A survey of intestinal parasites was performed in South Vietnam. Samples were collected from 717 Vietnameses, 1,933 U.S. Forces, 433 stool specimens of Korean Troops in South Vietnam. And 114 of Korean Army patients in home land were also examined as a control. Findings were discussed with others and summarized as follows: A parasitic rate, incidence in general, was 44.8 %. Koreans in South Vietnam showed 82.4 % of infection rate, Vietnamese 64.6% and U.S. Forces 26.1 %. Korean home patients revealed 93.9 %. Following 10 species of helminths ova and 5 kinds of protozoa were found: Ascaris lumbricoides, Hookworm, Trichocephalus trichiurus, Strongyloides stercoralis, Trichostrongylus orientalis, Enterobius vermicularis, Metagonimus yokogawai, Clonorchis sinensis, Hymenolepis nana, Taenia sp., Entamoeba histolytica, Entamoeba coli, Endolimax nana, Giardia lamblia and Trichomonas hominis. The incidence of Ascaris lumbricoides among Koreans in South Vietnam was 15.9 %, much less than Korean home patients. The infection rate of A. lumbricoides in Saigon residents was 47.2% but in Chulai 36.8% and in Quinhon 35.8 %. Trichocephalus trichiurus was most frequently found in Koreans. Quinhon residents showed 78.7 % positive in hookworn infection and Chulai 24.7 %. In Saigon, on the contrary, infection rate was only 3.1 %. No Strongyloides stercoralis, but two cases of Trichomonas hominis were found among Koreans in South Vietnam. U.S. Forces showed higher incidences than Koreans and Vietnameses in the incidences of Entamoeba histolytica and Endolimax nana. Most of the U.S. Forces revealed single infection. Korean home patients showed the highest per centage of polyparasitism. Non-autochthonous infections in Korea could not be found among Koreans in this survey.

A Study of Clothings for Cold Prevention: Protective Effects of viny1 Sheet against Wind / 예방의학회지

Three combinations of cloths were evaluated for the protective effects of different kinds of clothings in cold environments. Table 1 shows tile components of tile three models of clothings. A prototype was made by putting a sheet of vinyl at the middle layer of raw cotton in a fabric-quilt cloths. A glove mannequin was covered by each of these cloths. The globes contained 1,000 cc of hot water about 40 degrees C. Tele-thermisters were fixed in order to check the temperature of cloths space and water temperature for evaluation of caloric-loss and climate of clothings. Results are summarized as follows : 1) Without wind, there is no significant difference of air temperatures between ski-parka and quilt wear clothing. 2) The prototype with vinyl sheet best protects against wind, the next is the ski-parka. Quilt-wear protects the least. 3) It is well-known that a working-clothing needs not have any separate liners nor outers. 4) For innermost layer of a clothing preventing cold, a cotton-fabrics is recommended and a water-proof cloths for outer layer. 5) Heat-loss was calculated from the cooling degrees of water. Calorie-loss was 910ca1/m2/hr. when bared, but with the prototype of vinyl sheets the calorie-loss was 350cal/m2/hr. (38.5% of bared). Quilt-wear and ski-parka were 380(41.8%) and 440 cal/m2/hr. (48.4%) respectively.

Studies on the parasitic helminths of Korea III. Nematodes and cestodes of rodents

A survey for nematode and cestode parasites of rodents in Korea has been carried out at the areas of Chulwon, Kumwha, Pochon, Paju and Chungpyong, Kyunggi-Do. A total of 300 rodents of seven species was examined, comprising of 219 A. agrarius, 33 R. norvegicus, 8 R. alexandrinus, 14 Mus musculus yamashinai, Microtus fortis pellceus, 21 Crocidura russula and a Cricetulus trition nester. The following fifteen species belonging to thirteen genera were identified: NEMATODA: Heterakis spumosa, Syphacia obvelata, Nippostrongylus muris, Protospirura muris, Capillaria hepatica, Capillaria sp., Heligmosomum sp., Heligmosomoides sp., Rictularia sp. and Gongylonema sp. CESTODA: Hymenolepis nana, Hymenolepis diminuta, Raillietina coreensis, Paranoplocephala sp. and Cysticercus fasciolaris(the larva of Taenia taeniaeformis).

A Case report of sparganosis

A case of sparganosis was presented. The patient was a 43-year-old Korean male who had a history of having eaten raw flesh of snake and frog in Keoje Island during 1950 to 1952 for the purpose of treatment of arthritis by the oriental custom. In the summer, l959, he had slight itching sensation in the left lower scrotal area. A few months later, he noticed the appearance of a peanut-sized mass in that area. However, the mass enlarged gradually to a hen's egg size during two years. On surgical exploration, the mass was found to be a fibro-connective tissue capsule(3 to 4 cm in diameter) in the lower left scrotal area. From the capsule three larvae(l9 to 28 cm by 2 to 6 mm) were freed by dissection without much difficulty. The sources of infection of some formerly reported sparganosis in Korea were discussed. It is most probable that human sparganosis is acquired by ingestion of raw flesh of snake and frog in this country.