The authors carried out two series of field test to determine the basic lines of DDT and Dieldrin susceptibility of Anopheles sinensis at Andong(1961) and Yoju(1962), where malaria endemicity is relatively high in Korea. Tests were performed in accordance with the standard method established by the World Health Oraganization(1960). The results were summarized as follows: The LC-50 of DDT for A. sinensis caught at Andong as 1.5 %, while for the same species in Yoju was 1.3 %. The LC-50 of Dieldrin for A. sinensis caught at Andong was 0.075 %, while the LC-50 for the same species at Yoju was 0.07 %. These results therefore indicate Anopheles sinensis, as the malaria vector species in Korea, is susceptible to DDT and Dieldrin.
parasitology-protozoa-Plasmodium vivax ; chemotherapy-malaria ; Anopheles sinensis ; DDT ; Dieldrin

The species composition, population density, and seasonal prevalence of vector mosquitoes in an inland area of Kyungpook province were studied, based on light trap and human bait trap collections, and the recent patterns of infestation for infective larvae of Brugia malayi in these vector hosts were investigated from May to November in 1985. Nine species in four genera of mosquitoes were collected by light trap, human bait trap, and/or by nets. Anopheles sinensis Wiedemann was the most abundant species collected by light traps during this year. Culex tritaeniorhychus Giles was the second abundant species, and Aedes vexans nipponii(Theobald) ranked third in total abundance. The earlist time when A. sinensis were found was the middle of May. At that time the temperature ranged from 14.3 C to 22.8 C and the humidity 53-90 per cent. The month of highest average nightly catch was July, when the temperature was betweeen 21.5 C and 30.6 C and the humidity 72-91 per cent. The peak time of biting activity of mosquitoes was different in each month, i.e. between 22:00-23:00 in July, and 20:00-21:00 hours in September, when the temperature was between 24.3 C and 26.5 C and the humidity 73-88 per cent in the field. While infective larvae of B. malayi were reported to have been found in one species of mosquito in 1975, no larvae were found in any species collected in this survey.
parasitology-helminth-nematoda ; arthropoda ; Brugia malayi ; Anopheles sinensis ; epidemiology

In order to determine the seasonal prevalence and population density of vector mosquitoes in Kyungpook province, a survey based on average number of female mosquito per trap-night, were carried out during the period from May to November in 1984. Among the 34,571 mosquitoes collected in Kyungsan county in animal shelters and human dwellings by light traps, approximately 45.0 % were Culex tritaeniorhynchus, 34. 0 % per cent Culex pipiens pallens, and 19.0 per cent Anopheles sinensis. By comparison, distribution of mosquito species in Ankang town, in which Japanese encephalitis had been reported in the past, were quite different and A. sinensis was the most abundant species, being constituted in 75.8 per cent, followed by C. tritaeniorhynchus(23. 2 percent), and C. pipiens pallens(0. 6 per cent). In the general patten of seasonal prevalence, C. tritaeniorhynchus first appeared in mid-June, and trapped in large numbers during the periods from mid-August to early September, showing a simple sharply pointed one-peaked curve, while C. pipiens pallens was found to be active through almost the entire season showing irregular curves with several peaks. The trend of seasonal distribution of A. sinensis was similar to that of C. tritaeniorhynchus, but the earliest dates of appearance and disappearance different form that of C. tritaeniorhynchus. The results of hourly catches of mosquitoes by human baited traps have clearly shown the differences in the biting rhythm among the vector mosquitoes of this province, such as the facts that C. tritaeniorhynchus and A. sinensis are rather constantly active all through a night with more or less inconspicuous peaks twice a night, while C. pipiens pallens exhibits an irregular curve, and the numbers of A. vexans nipponii, C. vagans and Armigeres subalbatus are very small and are not sufficient for estimating the biting rhythm. Four genera and fourteen species of larval mosquitoes collected from eighteen kinds of habitats which classified according to the categories followed by Bates(1949). The main breeding sites contributing to peak C. tritaeniorhynchus adult densities in this surveyed areas were evidently ricefields, ground pools, puddles and swamps and marshes, etc. Summarizing the results, this study indicated that the highest population density of C. tritaeniorhynchus was encountered in late August and early September, showing simple sharply pointed one-peaked curve.
parasitology-arthropoda ; mosquito-epidemiology ; Culex tritaeniorhynchus ; Culex pipiens pallens ; Anopheles sinensis

On epidemiological grounds, Anopheles sinensis has been suspected for many years to be the malaria vector in Korea. Of 7,517 dissections of A. sinensis, one specimen was found for the first time in Korea naturally infected with sporozoites in August 1962. Experimental infection of A. sinensis with Plasmodium vivax had been successfully conducted at earlier date.
mosquito-parasitology ; malaria-vector ; arthrooda-Anopheles sinensis ; protozoa-Plasmodium vivax ; epidemiology-Korea

During the summer season(July-August) in 1967, the insecticide tests for resistance on adult A. sinensis and C. tritaeniorhynchus were carried out in Gobu-Myun Jeongup-Gun, Chollapuk-Do, where many Japanese encephalitis cases occur every year. The mortality by 4.0% DDT in A. sinensis was 88.9% and by 4.0% dieldrin was 84.4%. Therefore the LC-50 of DDT for A. sinensis was 1.75%, while LC-50 of dieldrin was 1.1%. The mortality by 4.0% DDT in C. tritaeniorhynchus was 36.7%, and by 4.0% dieldrin was 6.0% The result indicates that A. sinensis in Korea is susceptible to DDT and resistant to dieldrin. C. tritaeniorhynchus is highly resistant to both DDT and dieldrin.
parasitology-arthropoda ; vector ; mosquito ; Culex tritaeniorhynchus ; Anopheles sinensis ; chemotherapy ; DDT ; dieldrin

This paper is the result of adult female mosquito and larval collection in U.S. Army Installations in Korea from 1979 to 1983. New Jersey light traps ere operated for ault collection from May to October. The primary concern of this surveillance is to determine when to recommend insecticide spraying for mosquito control in the Army areas. The 5th Preventive Medicine Unit have developed an "index" level of female mosquitoes in a light trap similar to other U.S.Army Agencies in other parts of the world. When 10 female mosquitoes are reached on two consecutive trap-night, or 5 known vector females are collected, fogging is recommended in the trap areas. Mosquito collections were conducted in 12 U.S. Army areas by operating 39 New Jersey light traps. Mosquitoes collected from the areas were identified to be 17 species comprising 3 genera. Anopheles sinensis(40%). Culex tritaeniorhyncus(31%), Aedes vexans nipponii(19%), and Culex pipiens pallens(10%) appeared to be the most common species in the area. The species, population density and monthly appearance of adult mosquitoes were found to be almost the same in the all provinces involved. And Japanese encephalitis vector mosquitoes, Culex tritaeniorhyncus, showed their seasonal fluctuation from July to September with a peak in August each year. 3. Larval habitats confirmed in the Army areas were categorized into 16 types as shown in Table The mosquito larvae collected in those habitats were identified to be 15 species representign 4 genera. Most breeding sites in the Army areas were those which are activated during the wet season. More mosquitoes were collected from the Kyungki province than from the other provinces. The reason for more collection of mosquitoes from military installations in the Kyungki provinces appears to be the geographic characteritics surrounded by rice fields, marshes and other stagnant water areas.
parasitology-arthropoda-mosquito ; taxonomy ; epidemiology ; Anopheles sinensis ; Culex tritaeniorhyncus ; Aedes vexans nipponii ; Culex pipiens pallens