Global warming is gradually becoming a severe problem due to increase in greenhouse gas. Global warming and urbanization in Korea are progressing faster than the global average. The occurrence of indigenous diseases (Malaria, Japanese encephalitis, etc.) is increasing due to the expansion of the distribution of vectors caused by global warming and the increase in the possibility of inflow of imported vectors, and the possibility of inflow of foreign infectious diseases (Dengue fever, West Nile fever, etc.) is increasing. It is necessary to cope with the inflow and spread of vector-transmitted diseases considering climate and environmental changes through nationwide and long-term surveillance. The purpose of this study was to suggest a method for predicting and controlling the occurrence of mosquitoes in the metropolitan area by synthesizing mosquito studies conducted in the metropolitan area of Korea.
The first chapter was conducted as part of the research on Regional Vector Surveillance Center for Climate Change of the Korea Centers for Disease Control and Prevention. The study site was Seoul and other metropolitan areas. Monitoring was divided into daily density monitoring, mosquito species and density monitoring, trap efficiency analysis, and pathogen testing. The study site was divided into 4 points, and daily density monitoring was performed at St. 1 (Urban) and St. 2 (Rural). The trap efficiency was performed at St. 3 (Urban) and St. 4 (Migratory bird sanctuary). Mosquito species and density monitoring and pathogen testing were performed on mosquitoes collected from all sites. Mosquito density in the metropolitan area increased from April, and the first explosion occurred around July. After a sharp decrease in the population due to typhoons and heavy rains around August, it increased again around September, recording a second peak, and then decreased sharply from October. As a result of analyzing mosquito species in the metropolitan area, 6,789 individuals, 7 genus, and 14 species were collected in 2021, and Culex pipiens were 4,216 individuals (30.33±4.72, 79.67%) as the dominant species, and Ochlerotatus koreicus were 461 individuals (10.72±3.42, 8.71%) followed. Culex pipiens (St. 1 : 95.89%, St. 2 : 55.00%, St. 3 : 63.25%, St. 4 : 84.31%) appeared as the dominant species at all sites. The collection results for each trap showed that the BG-Sentinel trap had about 2.1 times higher collection efficiency than the LED trap. The mosquitoes collected through this study were tested for Flavivirus by RT-PCR, but all were confirmed as negative. However, as the habitat of infectious disease vectors, such as Culex tritaeniorhynchus, Aedes albopictus, Anopheles spp., Culex pipiens, Aedes vexans, and Ochlerotatus dorsalis, has been confirmed, the importance of surveillance of infectious disease vectors in the metropolitan area has emerged. The results of this study is highly considered to be able to be in use for disease prediction and epidemic prevention.
The second chapter was carried out for the purpose of providing citizens with a forecast of the mosquito prevalence for the year. It was held by dividing the regions of Seoul into districts, installing mosquito monitoring equipment, and developing a prediction formula based on the mosquito population, meteorological factors, and spatial information factors of the past year. To derive the mosquito population prediction formula, mosquito population data from 2015 to 2021, meteorological factors, and spatial information factors were collected. For mosquito population, data from 2 DMS units installed in each districts of Seoul was used, and for meteorological factor, ASOS of the Korea Meteorological Administration was used, and for spatial information factors, land cover map and altitude data were used. In addition, the mosquito population prediction formula was calculated by dividing the landscape element into riparian, residence area, and park according to the DMS installation location. As a result of the suitability analysis using a simple regression analysis between the predicted mosquito population of the derived prediction formula and the observed mosquito population collected in 2021, r² was found to be 0.756, and the accuracy was 91.42±6.02%, showing high accuracy. The mosquito population prediction formula derived through this study is expected to have a positive effect on mosquito control as well as population prediction, and is anticipated to effectively reduce mosquito-related damage.
The third chapter was conducted for the purpose of proving the mass trapping effect of physical control, an eco-friendly mosquito control method. The study period was approximately one month (from July 2 to July 30, 2018). 26 units of MOS-HOLE PRO and 5 units of DMS were used each outside and inside the research site. As a result of the study, the total number of mosquitoes captured by MOS-HOLE PRO traps during the study period was 186,899, and 7 genus and 12 species were identified. The genus composition consisted of Culex (121,476 individuals, 65%), Mansonia (35,385 individuals, 19%), Anopheles (18,926 individuals, 10%), and Aedes (11,112 individuals, 6%). Comparing mean mosquito populations in MOS-HOLE PRO traps (CO₂ emission rate of 600ml/min) and DMS traps (300ml/min), approximately 2.48 times more mosquitoes on mean in MOS-HOLE PRO traps with increased CO₂ emission was confirmed to be caught. The total number of mosquitoes collected by DMS for each year was converted into 100% and the percentage of mosquitoes collected in each month was analyzed. In 2018 alone, when the physical control was operated, the ratio was 20% in July, and in 2017 and 2019, when the physical control was not operated, the ratio was shown to be 40~50%. This suggests that mass trapping, a physical control, is effective in suppressing the mosquito population introduced from the outside. It was demonstrated that the effectiveness of physical control using the MOS-HOLE PRO trap, and proposed the possibility of establishing a Mosquito Free Zone by successfully blocking the inflow of externally generated mosquitoes. It is regarded that physical control methods can be a reliable alternative to properly control adult females outdoors.