Three anopheline mosquitoes in Korea were studied for their abilities as vectors for Plasmodium vivax. The female mosquitoes of Anopheles lesteri, An. pullus and An. sinensis were allowed to suck malaria patient blood until fully fed, and they were then bred for 2 weeks to develop from malaria parasites to sporozoites. The result from the above confirmed the sporozoites in one An. lesteri of one individual and five An. sinensis of six individuals. We also reconfirmed that An. sinensis was the main vector to transmit malaria and An. lesteri as well as An. sinensis were able to carry Korean malaria parasites. Therefore, we propose that diversified study is needed to manage malaria projects.
Adult ; Animals ; Culicidae/*parasitology/*physiology ; Female ; Humans ; *Insect Vectors ; Korea ; Malaria/parasitology/transmission ; Male ; *Plasmodium vivax

Since the national malaria eradication service (NMES) was implemented in 1959, extensive malariometric survey were conducted throughout the country. A total of 73,859 malaria cases of Plasmodium vivax were confirmed out of 268,259 blood smears through passive and active case detection (PCD and ACD) in 1960~1969 including chloroquine/ pyrimethamine combined tablets for the presumptive treatment of all of fever cases. The majority of the positive cases occurred in Gyeongsang buk-do, revealing 62,859 cases as of 85.2%, followed by Gyeonggi-do 5,844 cases (7.9%), Chungcheong buk-do 3,458 cases (4.7%), Gangwon-do 812 cases (1.1%), and 29 cases developed in Jeju-do. ACD was more sensitive and advantageous for detecting the malaria cases over PCD in the pilot study area. The high endemic area was located in the north Gyeongsang buk-do and north east Gyeonggi-do. The malaria incidence was high in the age group under 14 years in malaria foci, and that was low in non-malarious area. High parous rate (77.7%) and survival rate (91.4%) of the vector mosquitoes were shown in malaria foci, which were hilly or mountainous area. On the other hand, low parous rate (50.6%) and survival rate (42.7%) were found in non-malarious area, the rice field of south western part of the country even in abundance of vector mosquitoes. NMES had contributed the control of the malaria by carring out the residual DDT focal spray, mass drug administration, radical treatment of the positive cases, and mass blood survey in the heavy malarious area. Since then malaria disappeared rapidly, and no indigenous case was reported after 1984. In order to ascertain whether this country was malaria-free or not, mass blood survey was carried out for the juveniles, adolescents and adults in Yeongju-gun Gyeongsangbuk-do in 1986 where the highest incidence of malaria was recorded during the 1960s. The result showed no positive case at all. However vivax malaria reemerged, and made a dramatic resurgence since 1993 in the demilitarized zone (DMZ) bordering North Korea, and expanded toward eastern and southern part of the country year after year, totaling 14,089 cases including U.S. army by the end of 2000 in spite of the strong activities of antimalaria in the Republic of Korea. So vector control including the encouragement of the livestock farming in the malaria endemic area must be more sensitive and effective measure to reduce the risk of malaria transmission by the eliminating the dangerous age of mosquitoes in the points of characteristics of the Korean strain of parasites such as the mild symptoms, long-term incubation period and asymptomatic parasitaemia. Focal application of thermal fogging and mist spray of insecticides would be certainly effective in preventing the vector mosquitoes from infecting the gametocytes of malaria for the first peak of multi malaria cases in the early season of the year. All of the civilians who are in the high risk area for malaria should be forced to sleep under the permethrin impregnated mosquito nets. All of the soldiers near the DMZ are strongly recommended to take the combined tablets of chloroquine/ pyrimethamine instead of the single base of chloroquine at present to prevent the action of source of infection of the reservoirs and the completion of the sporogonic stages of the vector mosquitoes because the vector control activities are not allowed in the DMZ. The experts of entomologists and malariologist of the South and North Korea should discuss the antimalaria programme to eradicate the malaria from the Korean peninsular near future.
Adolescent ; Adult ; Chloroquine ; Culicidae ; DDT ; Democratic People's Republic of Korea ; Epidemiology ; Fever ; Gangwon-do ; Gyeonggi-do ; Gyeongsangbuk-do ; Hand ; Humans ; Incidence ; Insecticides ; Jeju-do ; Korea* ; Livestock ; Malaria* ; Malaria, Vivax ; Military Personnel ; Mosquito Nets ; Parasites ; Permethrin ; Pilot Projects ; Plasmodium vivax ; Pyrimethamine ; Republic of Korea ; Seasons ; Survival Rate ; Tablets ; Weather

Purpose: This study aimed to investigate the effects of the nursing practice environment and self-leadership on person-centered care provided by oncology nurses. Methods: This cross-sectional study included 145 nurses who worked in oncology wards at eight university hospitals in Seoul, Daejeon, and Chungcheong Province with at least six months of experience. Data were collected using a self-administered survey and analyzed using descriptive statistics, Pearson correlation coefficients, the t-test, analysis of variance, and hierarchical multiple regression analysis in SPSS version 26.0. Results: Person-centered care was significantly correlated with the nursing practice environment (r=0.27, P＜0.001) and self-leadership (r=0.40, P＜0.001), and the nursing practice environment was correlated with self-leadership (r=0.380, P＜0.001). Hierarchical multiple regression analysis showed that the nursing practice environment was a significant predictor of person-centered care (β=0.31, P＜0.001), after adjusting for covariates including monthly salary, total clinical career, and the position of oncology nurses. Self-leadership was a significant predictor of person-centered care (β=0.34, P＜0.001) after controlling for the nursing practice envi-ronment, along with covariates. The final model explained 18.7% of the variance in personcentered care. Conclusion Our findings emphasize the importance of the nursing practice environment and nurses’ self-leadership for providing person-centered care in oncology care units. Educational programs to reinforce nurses’ self-leadership and administrative support for nursing practice are necessary to improve oncology nurses’ capability to provide person-centered care.

Purpose: This study aimed to investigate the effects of the nursing practice environment and self-leadership on person-centered care provided by oncology nurses. Methods: This cross-sectional study included 145 nurses who worked in oncology wards at eight university hospitals in Seoul, Daejeon, and Chungcheong Province with at least six months of experience. Data were collected using a self-administered survey and analyzed using descriptive statistics, Pearson correlation coefficients, the t-test, analysis of variance, and hierarchical multiple regression analysis in SPSS version 26.0. Results: Person-centered care was significantly correlated with the nursing practice environment (r=0.27, P＜0.001) and self-leadership (r=0.40, P＜0.001), and the nursing practice environment was correlated with self-leadership (r=0.380, P＜0.001). Hierarchical multiple regression analysis showed that the nursing practice environment was a significant predictor of person-centered care (β=0.31, P＜0.001), after adjusting for covariates including monthly salary, total clinical career, and the position of oncology nurses. Self-leadership was a significant predictor of person-centered care (β=0.34, P＜0.001) after controlling for the nursing practice envi-ronment, along with covariates. The final model explained 18.7% of the variance in personcentered care. Conclusion Our findings emphasize the importance of the nursing practice environment and nurses’ self-leadership for providing person-centered care in oncology care units. Educational programs to reinforce nurses’ self-leadership and administrative support for nursing practice are necessary to improve oncology nurses’ capability to provide person-centered care.

Field trials evaluating selected commercially available mosquito traps variously baited with light, carbon dioxide, and/or octenol were conducted from 18 - 27 September 2000 in a malarious area near Paekyeon-ri (Tongil-Chon) and Camp Greaves in Paju County, Kyonggi Province, Republic of Korea. The host-seeking activity for common mosquito species, including the primary vector of Japanese encephalitis, Culex tritaeniorhynchus Giles, was determined using hourly aspirator collections from a human and propane lantern-baited Shannon trap during hours when temperatures exceeded 15oC. The total number of mosquitoes and number of each species captured during the test was compared using a block design. Significant differences were observed for the total number of mosquitoes collected, such that, the Mosquito MagnetTM with octenol > Shannon trap > ABC light trap with light and dry ice > Miniature Black Light trap (manufactured by John W. Hock) >; or = New Jersey Trap > ABC light trap with light only. Significant differences in numbers collected among traps were noted for several species including: Aedes vexans (Meigen), Anopheles lesteri Baisas and Hu, An. sinensis Weidemann, An. sineroides Yamada, An. yatsushiroensis Miyazaki, Culex pipiens L., Cx. orientalis Edwards and Cx. tritaeniorhynchus. Host-seeking activity for most common species showed a similar bimodal pattern. Results from these field trap evaluations can significantly enhance current vector and disease surveillance efforts especially for the primary vector of Japanese encephalitis, Cx.tritaeniorhynchus.
Animals ; *Appetitive Behavior ; Culicidae/*physiology ; Encephalitis, Japanese ; Humans ; Insect Vectors ; Korea ; Light ; Mosquito Control/*instrumentation/methods ; Seasons

To evaluate the factors that determine the transmission level of vivax malaria using vectorial capacity, entomological surveys were conducted from June to August, 2000. From 6 nights of human-bait collection in Paju, the human biting rate (ma) was counted as 87.5 bites/man/night. The parity of Anopheles sinensis from human baiting collections fluctuated from 41% to 71% (average 48.8%) of which the rate gradually increased as time passed on: 35.2% in Jun.; 55.0% in July; 66.2% in Aug. From this proportion of parous, we could estimate the probability of daily survival rate of An. sinensis to be 0.79 assumed with 3 days gonotrophic cycle and the expectancy of infective life through 11 days could be defined as 0.073. Blood meal analysis was performed using ELISA to determine the blood meal source. Only 0.8% of blood meals were from human hosts. We could conclude that An. sinensis is highly zoophilic (cow 61.8%). Malaria is highly unstable (stability index < 0.5) in this area. From these data, vectorial capacity (VC) was determined to be 0.081. In spite of a high human biting rate (ma), malaria transmission potential is very low due to a low human blood index. Therefore, we could conclude that malaria transmission by An. sinensis is resulted by high population density, not by high transmission potential. For this reason, we need more effort to decrease vector population and vector-human contact to eradicate malaria in Korea.
Animals ; Anopheles/*parasitology ; Human ; Insect Vectors ; Korea ; Malaria, Vivax/parasitology/*transmission ; Parity ; Plasmodium vivax/*pathogenicity/physiology ; Population Density

In order to study the range of flight and feeding activity of Anopheles sinensis, the dispersal experiment was conducted in Paju city, located in the northern part of Gyeonggi-do, Republic of Korea, during the period of 7th to 28th September 1998. Unfed females An. sinensis were collected in cowshed and released after being marked with fluorescent dye at 23:00 hours on the same day. Released female mosquitoes were recaptured everyday during 21 days using light traps, which were set at 10 sites in the cowsheds located 1, 3, 6, 9 and 12 km north-northwest and north-northeast and at 3 sites located 1, 6 and 9 km toward south-west from the release point. In addition, to study the longest flight distance in one night, we set the light traps at 16 and 20 km toward north-northeast from the release site. All the collected mosquitoes were placed on filter papers and observed on UV transilluminator after treatment with one drop of 100% ethanol. Out of 12,773 females of An. sinensis released, 194 marked females mosquitoes were recaptured, giving 1.52% recapture rate. Of 194, 72 mosquitoes (37.1%) were recaptured in light traps from three places set at 1 km from the release point, 57 mosquitoes (29.4%) from two places at 1-3 km, 41 mosquitoes (21.1%) from three places at 3-6 km, 20 mosquitoes (10.3%) from three places at 6-9 km, and 4 mosquitoes (2.1%) from two places at 9-12 km. Since 170 female mosquitoes (87.6%) out of 194 marked mosquitoes were captured within 6 km from the release point, this flight radius represents the main activity area. An sinensis was found to be able to fly at least 12 km during one night.
Animals ; Anopheles/*physiology ; Entomology/methods ; Feeding Behavior ; Female ; *Flight, Animal ; Fluorescent Dyes ; Korea ; Support, Non-U.S. Gov't ; Time Factors

House-residual spraying and insecticide-treated bed nets have achieved some success in controlling anthropophilic and endophagic vectors. However, these methods have relatively low efficacy in Korea because Anopheles sinensis, the primary malaria vector, is highly zoophilic and exophilic. So, we focused our vector control efforts within livestock enclosures using ultraviolet black light traps as a mechanical control measure. We found that black light traps captured significantly more mosquitoes at 2 and 2.5 m above the ground (P < 0.05). We also evaluated the effectiveness of trap spacing within the livestock enclosure. In general, traps spaced between 4 and 7 m apart captured mosquitoes more efficiently than those spaced closer together (P > 0.05). Based on these findings, we concluded that each black light trap in the livestock enclosures killed 7,586 female mosquitoes per trap per night during the peak mosquito season (July-August). In May-August 2003, additional concurrent field trials were conducted in Ganghwa county. We got 74.9% reduction (P < 0.05) of An. sinensis in human dwellings and 61.5% reduction (P > 0.05) in the livestock enclosures. The black light trap operation in the livestock enclosures proved to b9e an effective control method and should be incorporated into existing control strategies in developed countries.
Animals ; Anopheles/*radiation effects ; Female ; Housing, Animal ; Humans ; Korea ; Mosquito Control/*methods ; *Ultraviolet Rays

The objectives of the present study were to (1) determine the susceptibility of Anopheles sinensis to Korean isolates of Plasmodium vivax, (2) establish a method to collect large quantities of P. vivax sporozoites for use as antigen in seroepidemiological studies, and (3) investigate the characteristics of Korean isolates of P. vivax sporozoites. Females of Anopheles sinensis were collected at non-epidemic area, Seokwha-ri, Cheongwon-gun and Chungcheongbuk-do using tent-trap methods coupled with dry ice. The females were artificially infected with gametocytes of P. vivax using blood obtained from P. vivax malaria patients. Individual mosquitoes were infected using either a parafilm-covered glass feeding apparatus or were allowed to feed on naturally infected volunteers. Mosquitoes were sacrificed between 16 and 18 days post-feeding and an enzyme-linked immunosorbent assay (ELISA) was used to detect sporozoites. Four (33.4%) of 12 mosquitoes, which were fed on naturally infected volunteers directly, were positive for sporozoites. In cases, the mosquitoes allowed to feed on whole blood which were extract from three different patients with heparin treated vacuutainers using a parafilm-covered glass apparatus. Two of 55 (3.6%) were positive which blood sample was maintained at room temperature for 8 hours, 1 of 68 (1.5%) was positive which blood was maintained at 4 degrees C for 24 hours and 1 of 47 (2.3%) was positive at 4 degrees C for 48 hours. The mean number of sporozoites was estimated about 818 (n = 8; range of 648-1,056) based on optical density values of ELISA.
Animals ; Anopheles/*parasitology ; Enzyme-Linked Immunosorbent Assay ; Human ; Korea ; Plasmodium vivax/isolation & purification/*pathogenicity ; Support, Non-U.S. Gov't

We investigated population densities of mosquitoes infected with sporozoites in three highly epidemic areas of Josan-ri and Jangpa-ri (Paju City) and Dongjung-ri (Yeoncheon County) in Korea. Anopheline mosquitoes were collected from both indoors and outdoors by human baiting collection method during the period of the first week of June to the second week of September 1999. Total 13,296 female mosquitoes were collected and 8,650 (65.1%) were Anophelines. Thirty seven percent (3,199) of the Anopheline mosquitoes were captured outdoors and 63.9% (5,531) indoors. Employing a sandwich enzyme-linked immunosorbent assay (ELISA), we analyzed a total of 7,820 Anopheline mosquitoes and found that 7 Anopheline mosquitoes were infected with sporozoites. The positive rate in Josan-ri was 0.14% (5/3,500) and 0.15% (2/1,370) in Jangpa-ri. The total positive rate in all three surveyed areas was 0.09% (7/7,820). The mosquitoes infected with the sporozoites were detected on June 28th (n=2), July 5th (n=1), July 19th (n=1), August 9th (n=1), September 6th (n=1), and the last one on September 13th (n=1). They were all classified as Anopheles sinensis, which showed positive reaction in ELISA test. Therefore it might be concluded that A. sinensis plays an important role in re-emerging malaria transmission in Korea.
Animals ; Culicidae/*parasitology ; Enzyme-Linked Immunosorbent Assay ; Female ; Human ; Korea/epidemiology ; Malaria, Vivax/epidemiology/parasitology/transmission ; Plasmodium vivax/*isolation & purification ; Support, Non-U.S. Gov't