Weekly changes in adult Anopheles species were monitored at Camp Humphreys (CH), Ganghwa Island (GH), and Warrior Base (WB), from May-October, 2009 to explore the relationship between Plasmodium vivax development and vector dynamics in the Republic of Korea (ROK). Adult females were trapped and dissected to determine parity for estimating longevity, mortality, and birthrate. A degree-day (DD) method was used to estimate the extrinsic incubation period (EIP) of P. vivax and duration of the gonotrophic cycle and other life stages. Anopheles sinensis was the predominant species, with satellite data showing peak abundance occurring after the period of maximum greenness. Abundance peaks were location dependent, comprised nulliparous and parous females, and timing could not be fully explained by DD estimation. Parity showed synchronicity between locations and years and was highest for September and lowest during maximum greenness. Mosquito longevity was predicted to exceed the EIP (when malaria transmission is possible) during weeks 29, 31, 34, and near the end of the season. Area-wide changes in parity suggest a common cause; information on local larval habitat and agricultural practices may explain location-specific effects. DD estimates of EIP and parity could be used to predict when conditions are suitable for P. vivax transmission. Journal of Vector Ecology 42 (2): 335-348. 2017.

A total of 150,805 culicine female mosquitoes were captured by Mosquito Magnet, black light, and New Jersey light traps, and at resting collections in the Republic of Korea from 2008 to 2010 as part of the U.S. Forces Korea malaria and Japanese surveillance programs. Mosquitoes were identified and culicine mosquitoes placed in pools of up to 30 mosquitoes each, by species and date of collection, and screened for flaviviruses using a reverse transcription-polymerase chain reaction assay. A total of 98/6,845 (1.4%) pools were positive by reverse transcription-polymerase chain reaction for Japanese encephalitis virus (JEV). A total of 92/2,031 (4.5%) pools of Culex tritaeniorhynchus were positive for JEV and accounted for 93.9% (92/98) of all JEV positive pools. A total of 4/804 (0.5%) and 2/175 (1.1%) pools of C. pipiens and C. bitaeniorhynchus, respectively, were positive for JEV. The JEV maximum likelihood estimations (estimated number of viral RNA positive mosquitoes per 1,000) for C. tritaeniorhynchus, C. bitaeniorhynchus, and C. pipiens were 1.71, 1.02, and 0.36 respectively. JEV is a severe health threat for local populations and of significant concern for nonimmune (unvaccinated) U.S. soldiers, civilians, and family members deployed to the Republic of Korea.

Light trap surveys of adult Culicoides Latreille in the Republic of Korea (ROK) resulted in the capture of three previously unreported species, C. nasuensis Kitaoka, C. pallidulus Yu and C. jacobsoni Macfie. These new records are supported by supplementary morphological descriptions and DNA barcodes (mitochondrial cytochrome oxidase I or COI). An updated checklist of species reported from the ROK is provided.

A total of 600 wild birds were analyzed for the causes of mortality in the Republic of Korea (ROK) from 2011 to 2013. Avian poxvirus (APV) infections were identified as the primary cause of mortality in 39% (29/74) Oriental Turtle Doves (Streptopelia orientalis). At necropsy, all 29 S. orientalis birds, of which, 76% (22/29) were juveniles, had severe diphtheritic lesions in their oral and nasal cavities and on their eyelids, which were the lesions of APV that resulted in mortality. We detected APV infection by chorioallantoic membrane inoculation and molecular study of the partial region of the P4b gene. All isolates belonged to the same APV strain and were identical to strains isolated from several different pigeon species in South Africa. Phylogenetically, the APV strain identified in S. orientalis belonged to subclade A2, which includes isolates from several species of pigeons from different parts of the world, including the United Kingdom, Germany, India, Egypt, Hawaii, Georgia, Hungary, South Africa, Tanzania, and the ROK. This identity indicated that this diphtheritic APV strain may be a potential pathogen of other pigeon species in the ROK and neighboring countries throughout the range of S. orientalis. However, reticuloendotheliosis virus insertion into the APV genome was not detected by PCR in any of the 29 APV infections. An identical strain of APV observed in S. orientalis was also detected in Culicoides arakawae (biting midge), with annual peak populations corresponding to the presence of APV in S. orientalis. Culicoides arakawae may be a primary vector of APV in S. orientalis. Active surveillance of APVs in wild birds and C. arakawae is needed to better understand the epidemiology of APVs, host-vector relationships, and its ecological effects on S. orientalis in the ROK.

Black light traps were used to measure the seasonal and geographical distribution of Culicoides spp. (biting midges or no-see-ums) at 9 cowsheds in the southern half of the Republic of Korea (ROK) from June through October 2010. A total of 25,242 Culicoides females (24,852; 98.5%) and males (390; 1.5%) comprising of 9 species were collected. The most commonly collected species was Culicoides punctatus (73.0%) followed by C. arakawae (25.7%), while the remaining 7 species accounted for <1.0% of all Culicoides spp. collected. The mean number of Culicoides spp. collected per trap night (Trap Index [TI]) was highest for C. punctatus (409.3), followed by C. arakawae (144.2), C. tainanus (4.1), C. oxystoma (1.2), C. circumscriptus (0.7), C. homotomus (0.6), C. erairai (0.4), C. kibunensis (0.3), and C. nipponensis (0.04). Peak TIs were observed for C. punctatus (1,188.7) and C. arakawae (539.0) during July and August, respectively. C. punctatus and C. arakawae have been implicated in the transmission of arboviruses and other pathogens of veterinary importance that adversely impact on animal and bird husbandry.