In the 21st century, the risk of the exotic pest being invaded is increasing due to the rise of trading activities. Oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), has been considered to very destructive invader as it is highly intrusive and has a wide host range. In this study, 2,299 samples were collected from 88 locations in 12 countries by quarantine and investigation. Among them, 608 individuals (including B. correcta) were used for COI DNA barcoding analysis based on Neighbor Joining method with P-distance model. Population genetics analysis was conducted for 510 individuals selected from 47 locations of 12 Southeast Asian countries using 15 microsatellite loci. The barcoding analysis resulted in that any clade was not clustered according to a geographical isolation but indicated geographically mixed populations. Population genetics analysis showed shared genetic structure between neighboring countries across borders. Genetic structure of most Korean quarantine groups was more similar to that of Taiwan, China and Thailand in the order of appearance than other countries.

Origin of Red imported fire ant (RIFA : Solenopsis invicta) is Central America, a tropical climate region. It has settled in the invasive area, causing various problems. In recent, Solenopsis invicta were discovered in Busan in 2017 and then in 2018 at a construction site in Busan, Pyongtaek, Incheon and in Daegu. This study aims to confirm the origin of invasive colonies of Solenopsis invicta. We tried to test previously developed microsatellite markers so that we establish the tracing protocol for molecular epidemiology of RIFA. We justified 66 microsatellite markers already developed using DNA from the RIFA found in Incheon Harbor. As results, 30 markers were selected to facilitate amplification and fragment analysis.

The oriental fruit fly, Bactrocera dorsalis (Hendel), has potential of serious damage to various vegetables or fruits, especially genus of Citrus, such as mandarin orange and tangerine in Korea, where its larvae do damages. Animal and Plant Quarantin Agency of Korea and Animsl Systematics Laboratory of Kunsans National University have collected the samples of oriental fruit fly in East Asian countries, Vietnam, Philippines, Myanmar, China, Cambodia, India Nepal and Laos. To confirm genetic differences and structure of B. dorsalis population samples collected from those countries, we analyzed 192 individuals from 28 locations over 7 countries using 15 microsatellite loci. In total samples, number of different alleles, number of effective alleles and Shannon's Information Index were 6.421±0.364 (standard error, SE), 3.664±0.137 (SE) and 0.902±0.030 (SE), respectively. Grand means (±SE) of observed and expected heterozygosity over all loci and populations were 0.534 (±0.018) and 0.597 (±0.017), respectively. Among all populations, Fst values ranged from 0.016 to 0.705 with averaging 0.194 (±0.026).

노로바이러스는 전세계적으로 모든 연령에게 급성 장염을 일으키는 주요 원인체이다. 본 연구는 국내 식품업계의 식품종사자를 대상으로 무증상 노로바이러스 감염의 유행성을 조사하였다. 2,729명의 식품종사자에서 29명 (1.06%)이 무증상 노로바이러스로 확인되었고 이 중 5명 (17.24%)은 노로바이러스 GI 양성이었고 24명(82.76%)은 노로바이러스 GII 양성이었다. 특히 유전자 염기서열 분석과 계통 분석에서 GII-4 유전자형이 가장 유행성이 높은 것으로 나타났으며 많은 수의 무증상 식품종사자는 노로바이러스 GII-4 에 감염되어있었다. 따라서 본 연구의 결과는 무증상 식품종사자가 노로바이러스 감염에 잠재적인 전파 원인일 가능성이 있음을 보여준다. 또한 이러한 결과는 노로바이러스 예방에 대한 식품업체의 교육의 필요성을 강조한다. 무증상 노로바이러스 감염에 더 많은 주 의를 기울여야 할 것이다.