Until recently, the single known exception to the rodent-hantavirus association was Thottapalayam virus (TPMV), a long-unclassified virus isolated from the Asian house shrew (Suncus murinus)Hantaviruses (family Bunyaviridae, genus Hantavirus) are medically important rodent-borne pathogens, causing hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). The belief in long-standing coevolutionary relationships between hantaviruses and their reservoir rodent host species is supported by virus and rodent gene phylogenies. That is, phylogenetic analyses, based on full-length viral genomic sequences and rodent mitochondrial DNA (mtDNA) or nuclear gene sequences, indicate that antigenically distinct hantaviruses segregate into clades, which parallel the evolution of rodents in the subfamilies Murinae, Arvicolinae, Neotominae, and Sigmodontinae (23,25,26,28,39,54). Previously, this phylogenetic insight has been successfully employed to direct the discovery of new hantaviruses, such as those found in the Korean field mouse (Apodemus peninsulae) (5) and the royal vole (Myodes regulus) (47).Renewed interest in the role of nonrodent reservoirs in the evolution of hantaviruses has been spurred by recent analysis of the entire genome of Thottapalayam virus (TPMV), a hantavirus isolated from the Asian house shrew (Suncus murinus) (10, 61), which revealed a separate phylogenetic clade, suggesting early evolutionary divergence from rodent-borne hantaviruses (44, 56). Armed with oligonucleotide primers designed on the basis of conserved regions of the TPMV genome and guided by long-ignored reports of serologic and antigenic evidence of hantavirus infection in shrews (20, 33, 52), we have previously detected genetically distinct hantaviruses in the Eurasian common shrew (Sorex araneus) from Switzerland (45); the Chinese mole shrew (Anourosorex squamipes) from Vietnam (46); and the northern short-tailed shrew (Blarina brevicauda), masked shrew (Sorex cinereus), and dusky shrew (Sorex monticolus) from the United States (1, 2) by reverse transcription-PCR (RT-PCR). Novel hantavirus genomes in Therese's shrew (Crocidura theresae) from Guinea (29); the vagrant shrew (Sorex vagrans), Trowbridge's shrew (Sorex trowbridgii), and the American water shrew (Sorex palustris) from the United States (H. J. Kang and R. Yanagihara, unpublished data); and the flat-skulled shrew (Sorex roboratus) and Laxmann's shrew (Sorex caecutiens) from Russia (Kang and Yanagihara, unpublished) have also been detected.Here, we report the antigenic, genetic, and phylogenetic characterization of a newly identified hantavirus, designated Imjin virus (MJNV), isolated from Ussuri white-toothed shrews of the species Crocidura lasiura (order Soricomorpha, family Soricidae, subfamily Crocidurinae) captured near the demilitarized zone (DMZ) in the Republic of Korea. The discovery of MJNV and other soricid-borne hantaviruses from widely separated geographic regions, spanning four continents,

Bird migration is a recurring annual and seasonal event undertaken by more than 100 species of birds in the southeast Asian and northeast Palearctic regions that pass through or remain for short periods from April to May and September to November at Hong-do Island, Republic of Korea (ROK). A total of 212 ticks (40 Haemaphysalis flava, 12 H. longicornis, 146 Ixodes turdus, 13 I. nipponensis, and 1 I. ornithophila) were collected from 65/2,161 (3.0%) migratory birds consisting of 21 species that were captured from January, 2008, through December, 2009, as part of the Migratory Birds Center, Hong-do bird banding program for studying bird migration patterns. Adult ticks were assayed individually while larvae and nymphs were pooled (1-22 and 1-6 ticks per pool, respectively) into 31 and 65 pools, respectively. Ticks were assayed for zoonotic pathogens by PCR using 16S rRNA, heat shock protein (groEL), and internal transcribed spacer (ITS) gene primers to amplify genera specific for Anapalsma, Bartonella, and Borrelia PCR amplicons. Using the 16S rRNA-based nested PCR, A. phagocytophilum (n=1) was detected in I. nipponensis collected from Zoothera sibirica and A. bovis (n=1) was detected in I. turdus collected from Emberiza chrysophrys. Borrelia turdi 16S rRNA genes (n=3) were detected in I. turdus and I. nipponensis collected from Turdus pallidus and Zoothera aurea. Borrelia spp. 16S rRNA genes (n=4) were detected in Ixodes ticks collected from Emberiza tristrami, T. pallidus, and Z. aurea. The Bartonella grahamii ITS gene (n=1) was detected by nested PCR assay in I. turdus collected from Z. aurea. These results provide insight into the potential role of migratory birds in the dispersal of ticks and associated tick-borne pathogens throughout their ranges in Asia.

Anopheles sinensis Wiedemann (63.3%) was the most abundant Anopheles mosquito captured at cowshed resting collections in malaria high-risk areas (northern Gyeonggi Province) near the demilitarized zone (DMZ) in Korea during 2005, followed by Anopheles kleini Rueda (24.7%) and Anopheles pullus M. Yamada (8.7%). At cowshed resting collections in malaria low-risk areas (Jeonnam and Gyeongnam provinces), An. sinensis accounted for 96.8% of all Anopheles spp. collected, followed by An. kleini Rueda (2.7%), whereas no An. pullus were collected. Three species, An. kleini (50.9%), An. pullus (29.0%), and An. sinensis (13.8%), accounted for nearly all of the 224 Anopheles spp. captured by New Jersey light trap near the DMZ. In addition, An. pullus and An. kleini captured by New Jersey light trap near the DMZ and assayed by enzyme linked immunosorbent assay for Plasmodium vivax circumsporozoite antigen concentrations were higher than An. sinensis sensu stricto (s.s.), indicating higher levels of sporozoites. In laboratory studies of four concurrent artificial membrane feedings on malaria-infected blood from patients, F1 progeny of An. kleini and An. pullus had higher infection rates (8.8 and 7.5%, respectively) than An. sinensis s.s. (4.2%). These data suggest that An. kleini and An. pullus and An. sinensis are vectors of malaria in Korea. Further studies are required to determine the role of these species in the transmission of P. vivax in the Republic of Korea.

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Ticks play an important role in transmission of arboviruses responsible for emerging infectious diseases, and have a significant impact on human, veterinary, and wildlife health. In the Republic of Korea (ROK), little is known about information regarding the presence of tick-borne viruses and their vectors. A total of 21,158 ticks belonging to 3 genera and 6 species collected at 6 provinces and 4 metropolitan areas in the ROK from March to October 2014 were assayed for selected tick-borne pathogens. Haemaphysalis longicornis (n=17,570) was the most numerously collected, followed by Haemaphysalis flava (n=3317), Ixodes nipponensis (n=249), Amblyomma testudinarium (n=11), Haemaphysalis phasiana (n=8), and Ixodes turdus (n=3). Ticks were pooled (adults 1-5, nymphs 1-30, and larvae 1-50) and tested by one-step reverse transcription polymerase chain reaction (RT-PCR) or nested RT-PCR for the detection of severe fever with thrombocytopenia virus (SFTSV), tick-borne encephalitis virus (TBEV), Powassan virus (POWV), Omsk hemorrhagic fever virus (OHFV), and Langat virus (LGTV). The overall maximum likelihood estimation (MLE) [estimated numbers of viral RNA positive ticks/1000 ticks] for SFTSV and TBEV was 0.95 and 0.43, respectively, while, all pools were negative for POWV, OHFV, and LGTV. The purpose of this study was to determine the prevalence of SFTSV, TBEV, POWV, OHFV, and LGTV in ixodid ticks collected from vegetation in the ROK to aid our understanding of the epidemiology of tick-borne viral diseases. Results from this study emphasize the need for continuous tick-based arbovirus surveillance to monitor the emergence of tick-borne diseases in the ROK.