As the malaria surveillance agency, the Korean Center for Control and Prevention (KCDC) has been monitoring malaria vector mosquito density and Plasmodium vivax infection since 2009. Anopheline mosquitoes were collected at 35 sites in Incheon, northern Gyeonggi and northern Gangwon Province using black light trap daily from April to October 2015. P. vivax infection of malaria vector mosquitoes tested by polymerase chain reaction (PCR). In 2015, a total of 57,926 malaria vector mosquitoes were collected among 138,119 mosquitoes. Three P. vivax positive pools were detected among 1,556 pools (13,745 individuals) and its minimum infection rate was 0.22. According to the monitoring result of malaria vector mosquitoes, early summer (June-July) could be an appropriate time for a malaria elimination campaign until September.

This study was performed to recognize species composition of Anopheline mosquitoes and infection rates of Plasmodium vivax in the northern part of South Korea. Adult mosquitoes were collected at 9 Republic of Korea (ROK) army installations in northern part of Geyonggi Province near the demilitarized zone (DMZ) using black light traps. Polymerase chain reaction (PCR) was used to identify collected Anopheline specimens and detect P. vivax from them. During June to August 2016, total 481 anopheline mosquitoes were collected and identified. Anopheles kleini was the most frequently collected (56.1%), and followed by An. pullus (16.6%), An. sinensis (16.2%), An. belenrae (7.5%) and An. lesteri (1.5%). 6 pools (4.0%) were positive for P. vivax among 150 pools. The minimum infection rates (MIR) was 1.24. Our ongoing study will provide a meaningful data for the effective malaria elimination strategy.

62세 여자가 약 7-10일간의 발열과 심와부 복통 및 오한으로 내원하여 단순한 급성 담석성 담낭염으로 진단받고 적극적인 시술과 약물치료를 받았으나, 임상경과가 호전되지 않고 비장경색의 합병증이 동반되어 추가 시행한 검사에서 삼일열 말라리아로 확진 받았다. 이후 절제된 담낭의 염증 소견은 말라리아 관련 급성 담낭염 소견을 시사하였다. 따라서 단순 급성 담석성 담낭염이라 하더라도 임상양상이 통상적인 회복소견을 보이지 않을 경우 다른 전신 질환에 합병된 담낭염의 가능성을 적극 고려해 보아야 한다.

Density of malaria vector mosquitoes, Anopheles mosquitoes, and infection of Plamodium vivax from the vector mosquitoes were monitored at 9 surveillance points in Incheonsi, 12 in Gyeonggi province and 7 in Gangwon province in the Republic of Korea (ROK) from April to October of 2010. The seasonal numbers of Anopheles mosquitoes collected weekly showed a high degree of variability. A total of 4,435 mosquitoes were captured using black light traps. Members of the Anopheles mosquito group were the most abundant species and accounted for 71.8% of the mosquitoes collected. The majority of this species were collected from Incheonsi (86.2%), particularly from Ganghwagun (84.8%). During June, populations of this species steadily increased and peak at second week of July. Thereafter, populations of this species decreased by the second week of August and increased by the third week of August, again. Anopheles mosquitoes steadily decreased from the fourth week of August. First Anopheles mosquitoes were reported in Wolgotri (15th weeks/year), Ganghwagun, Incheonsi, followed by Tanhyundong (16th weeks/year), Pajusi, Gyeonggi Province and Daemari (17th weeks/year), Cheolwongun, Gangwon Province. In Ganghwagun in which the most abundant malaria patients (102 patients) were reported, Anopheles mosquitoes demonstrated the highest species portion (over 70%) among collected mosquito species from July to September. Infection rate of P. vivax from the Anopheles mosquitoes also was the highest in Ganghwagun. In Gangwon and Gyeonggi provinces, collection rate of Anopheles mosquitoes and infection rate of P. vivax were relatively lower than those of Ganghwagun. Reported malaria patient cases in Gangwon and Gyeonggi provinces also were relatively lower than those of Ganghwagun. However, detailed results showed that there were some sites in which any correlation between malaria patients and vector mosquitoes were not. This may be resulted from size of surveillance area. Smaller size of surveillance area was, higher accuracy of analysis on correlation between vector mosquitoes and patients was. Further studies on relationship between malaria vector and patients may need for more accurate analysis, such as increase of collection site and so on.

As part of an on-going malaria surveillance effort conducted by the Korea Center for Disease Concectration & Prevention (KCDC), a total of anopheline mosquitoes was tested for the presence of Plasmodium vavax 18s protein. Mosquitoes were collected (using black light traps) from 2 quarantine stations (Kimpo branch office of Incheon Airport National quarantine station, Paju city and Sokcho branch office of Donghae National quarantine station, Goseong county), identified to species, and tested by PCR for the presence of P. vivax 18s protein. The quarantine stations is located near de-militarized zone in Republic of Korea . A total of 140 Anopheles bellene, 3 An. lesteri, 153 An. pullus, 238 An. kleini, and 1,523 An. sinensis was tested. Two Anopheles bellene, Seven An. kleini, and Nineteen An. sinensis were positive for P. vivax 18s protein. Anopheles sinensis is the predominent Anopheline mosquito encountered in the northern part of the ROK and is a known malaria vector. Other potential vectors include An. lesteri Baisas & Hu and An. yatsushiroensis Miyazaki. Anopheles bellene haven't been reported as vector of malaria until now. However, in this study, positive results were detected from An. bellene collected at Paju city and Goseong county, 27 May and 22 Jun, respectively. Anopheles bellene as potential vector of P. vivax might be further studied.