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A seasonal rodent-borne disease surveillance program was established at Dagmar North Training Area located near the demilitarized zone, Republic of Korea, from 2001 through 2005. Selected habitats surveyed included earthen banks separating rice paddies, fighting positions along a 5 m rock-faced earthen berm, and extensive tall grasses with various degrees of herbaceous and scrub vegetation associated with dirt roads, rice paddies, ditches, ponds, or the Imjin River. Of the nine species of small mammals captured, the striped field mouse (Apodemus agrarius), the primary reservoir for Hantaan virus, was the most frequently collected, representing 92.5% of the 1,848 small mammals captured. Males were captured similarly to females during the spring and summer seasons but were captured less frequently during the fall and winter seasons. Gravid rates were highest in the fall (25.5-57.3%) with the lowest rates during the summer (0.0-2.2%). Capture rates were the lowest along earthen banks separating rice paddies (5.5%) and highest in unmanaged tall grasses and crawling vegetation (15.3-43.5%). An increased knowledge of ecological factors that impact the abundance and distribution of small mammals and the associated ectoparasites and pathogens they harbor is critical for developing accurate disease risk assessments and mitigation strategies for preventing vector- and rodent-borne diseases among soldiers training in field environments.

The 1st confirmed record of Culiseta nipponica for the Republic of Korea was made at Osan Air Base and Tongilchon, Gyeonggi Province, and at the Incheon International Airport, Incheon metropolitan area, using carbon dioxide–baited light and Mosquito Magnet® traps. Larval surveys near adult collection sites during June and August 2013 were negative for Culiseta nipponica.

Migratory birds were captured, examined, banded and then released in accordance with a bird banding protocol of the Bird Research Center, National Park Research Institute, Korea National Park Service, from January-December 2010–2011 on Hong and Heuksan Islands, Jeollanam (Jeonnam) Province, in the Republic of Korea (ROK). Concurrently, ticks were collected from captured birds as part of a tick-borne disease surveillance program. A total of 381 ticks belonging to three genera and eight species – Ixodes turdus (297 ticks), Ixodes nipponensis (16), Haemaphysalis flava (46), Haemaphysalis longicornis (9), Haemaphysalis formosensis (5), Haemaphysalis ornithophila (6), Haemaphysalis concinna (1), and Amblyomma testudinarium (1)—were collected from 32 bird species belonging to 3 families. This is the first host report of A. testudinarium (1 nymph) collected from White’s Thrush, Zoothera aurea (Aves: Passeriformes: Turdidae), in the ROK. Most ticks were collected from birds during the months of April (44.1%) and November (54.2%).

A survey of reptile-associated ticks was conducted from March–October 2016 to determine their relative abundance, stage of development, and geographic and host distributions among lizards, skinks, and snakes in the Republic of Korea. A total of 30 lizards (3 species), 5 skinks (1 species), and 63 snakes (10 species) were collected. A total of 66 ixodid ticks belonging to two species (Ixodes nipponensis and Amblyomma testudinarium) were collected from 11/30 (36.7%) lizards, 2/5 skinks (40.0%), and 6/63 snakes (9.5%). Ixodes nipponensis was collected only from lizards and skinks, while A. testudinarium was collected only from snakes. The Amur Grass lizard, Takydromus amurensis, had the highest tick index (3.0) (total number ticks/total number hosts) among lizards and skinks, while the Short-tailed Mamushi (Viperidae), Gloydius brevicaudus, had the highest tick index (0.57) among snakes. Ixodes nipponensis larvae and nymphs accounted for 46.4% and 53.6% of all ticks collected from lizards and skinks, respectively, while only A. testudinarium nymphs were collected from snakes. Nymphs of both species of ticks were collected from lizards, skinks, and snakes from March-September, while I. nipponensis larvae were collected only from June-September. Ixodes nipponensis larvae and nymphs were preferentially attached on the foreleg axillae (66.1%), followed by lateral trunk (23.2%) and head and near the eye (10.7%) of lizards and skinks. None of the ticks collected from lizards, skinks or snakes were positive for severe fever with thrombocytopenia syndrome virus (SFTSV).

Soldiers from the Republic of Korea and the United States conducting peacetime military operations at various training sites and multiple range complexes located near the demilitarized zone separating North and South Korea are exposed to rodents and their potentially disease-carrying ectoparasites. These diseases include scrub typhus, murine typhus, and leptospirosis. Many of the training sites are rural or semi-rural, surrounded or co-located with various forms of agriculture, and are infested with rodents and insectivores (as well as their ectoparasites), which are commonly found in association with unmanaged tall grasses, scrub, and crawling vegetation habitats. For 5 years, rodents and insectivores were collected seasonally (spring, summer, fall, and winter) at firing points 10 and 60 near the demilitarized zone and serologically tested for the presence of scrub typhus, murine typhus, and leptospirosis antibodies. Of the nine species of small mammals collected, Apodemus agrarius, the common striped field mouse and known reservoir of scrub typhus, was the most frequently collected (90.6%). Only four of the nine species captured, A. agrarius (60.9%), Micromys minutus (100%), Mus musculus (55.6%), and Rattus norvegicus (46.7%), were positive for scrub typhus. Of all the small mammals captured, only A. agrarius was positive for murine typhus (0.3%) and leptospirosis (1.3%). Seasonal and annual prevalence rates based on weight and sex are presented.

Soldiers from the Republic of Korea and the United States conduct armistice military operations at Twin Bridges Training Area (TBTA) located near the demilitarized zone (DMZ) and are exposed to zoonotic disease pathogens that small mammals and their potentially disease-carrying ectoparasites transmit. TBTA is a 36 km2 rural training site with small villages and various forms of agriculture along its boundary. At TBTA, rodents, insectivores, and their ectoparasites are commonly found in association with unmanaged habitats of various densities of tall grasses, herbaceous plants, shrubs, briars, and crawling vegetation. Rodents and insectivores were collected during the winter (November-December 2005 and December 2006) and early spring (March 2007), and serologically tested for the presence of scrub typhus, murine typhus, and leptospirosis antibodies. Of the six species of small mammals collected, Apodemus agrarius, the common striped field mouse and known reservoir of scrub typhus, was the most frequently collected (96.1%), followed by Crocidura lasiura (2.5%), Micromys minutus (0.5%), Myodes regulus (0.5%), Mus musculus (0.3%), and Rattus rattus (0.1%). A. agrarius (56.1%), M. musculus (66.7%), M. minutus (25%), and R. rattus (100%) were positive for scrub typhus antibodies. Only A. agrarius (14.7%) and C. lasiura (4.5%) were positive for murine typhus antibodies, whereas only A. agrarius (1.5%) was seropositive for leptospirosis. Seroprevalence rates of scrub typhus and murine typhus based on weight and sex of A. agrarius are presented.

The Twin Bridges Training Area (TBTA) in the Republic of Korea consists of dirt roads, barren training areas, and forested hillsides adjacent to linear and broad expanses of tall grasses, herbaceous, and scrub vegetation. Of the six species of small mammals, the striped field mouse, Apodemus agrarius, was the most frequently captured (96.1%). Apodemus agrarius capture rates varied from 17.7 to 33.2% during three trapping periods. Gravid females were observed during November-December 2006 (8.4%) and March 2007 (5.1%). In 2005, the overall seroprevalence of Hantaan virus (HTNV) was high (34.4%) and lower during surveys in 2006 (14.2%) and 2007 (13.8%). Seroprevalence was directly correlated with weight increase of A. agrarius.

Mosquito larval surveillance for environmental monitoring and pest-control purposes was conducted monthly at dredged soil-dumping areas during the construction of a new harbor in Yongcheon Bay, approximately 5 km SE of Jinhae, on the SW side of Namsan (Mt. Nam) and across the bay from Su-do (Su Island) in Gyeongsangnam Province, Republic of Korea (ROK) from November 2007 through April 2008. During this study, mosquitoes collected as overwintering larvae were Aedes togoi in brackish rock pools along the seashore and Anopheles lindesayi japonicus along the vegetated margins of a slow-flowing drainage ditch and associated freshwater ground pools containing green algae. Overwintering An. lindesayi larvae also were collected along stream margins and stream pools of moderate- to fast-flowing mountain streams near Chungju (Chungcheongbuk Province) (October 2007 and March 2008) and Munsan (Gyeonggi Province) (September 2007 and April 2008). First and second instars were collected and identified in late September 2007 through February 2008. During March and April, collections were primarily 3rd and 4th instars, and by the end of April, pupae were collected. This is the first report of An. lindesayi japonicus overwintering as larvae in the ROK.

Adult mosquito surveillance was conducted during 2002 at 30 US military installations and training sites located in six provinces in the Republic of Korea (ROK). Adult mosquitoes were collected in New Jersey and dry ice -baited New Jersey light traps from 1 May through 15 October. Mosquito surveillance was conducted to determine threshold levels to initiate pesticide applications and identify malaria infection rates at selected Army installations and training sites. A total of 100,617 adults [82,410 (81.9%) females and 18,207 (18.1%) males] comprising 17 species and 7 genera were collected during 2002. The most common species collected were Culex tritaeniorhynchus Giles (49.5%), Anopheles sinensis Wiedemann (30.9%), Culex pipiens Coquillett(11.8%) and Aedes vexans nipponii (Theobald) (7.1%). Trap indices (TIs) varied widely for species over their range, due in part, to geographical distribution and degree of association with urban communities. Anopheles sinensis were collected at the same level while Culex tritaeniorhynchus increased by 27.2% in 2001, due in part to very high populations of Culex tritaeniorhynchus at Gunsan Air Base. The weekly population densities for some species were variable for each of the years, apparently as a result of variable annual weather conditions. None of Anopheles sp. assayed for plasmodium vivax (Pv) malaria infections by Enzyme Linked Immunosorbent Assay (ELISA) were positive.

Throughout Korea, small mammals are hosts to a number of disease-causing agents that pose a health threat to U.S. and Korean military forces while they conduct field-training exercises. A seasonal rodent-borne disease surveillance program was established at two firing points (FP), FP-10, and FP-60, and conducted over five years from 2001 through 2005 in response to hantavirus cases among U.S. soldiers. The ecology of these sites consisted primarily of tall grasses associated with semi-permanent and temporary water sources (drainage ditches and a small stream) and dry-land agriculture farming. Eight species of rodents and one species of insectivore were collected, including Apodemus agrarius, Micromys minutus, Mus musculus, Rattus norvegicus, Tscherskia triton, Microtus fortis, Myodes regulus, and Crocidura lasiura. The striped field mouse, A. agrarius, (primary reservoir for Hantaan virus, the causative agent of Korean hemorrhagic fever), was the most frequently collected, representing 90.6% of the 1,288 small mammals captured at both sites. Reported herein are the ecological parameters, seasonal population densities, and seasonal population characteristics associated with small mammals collected at two military training sites in the Republic of Korea.

A total of 1,618 ticks [420 individual (adults) and pooled (larvae and nymphs) samples], 369 rodents (Apodemus agrarius, Rattus norvegicus, Tscherskia triton, Mus musculus, and Myodes regulus), and 34 shrews (Crocidura lasiura) that were collected in northern Gyeonggi-do near the Demilitarized Zone (DMZ) of Korea during 2004-2005, were assayed by PCR for selected zoonotic pathogens. From a total of 420 individual and pooled tick DNA samples, Anaplasma (A.) phagocytophilum (16), A. platys (16), Ehrlichia (E.) chaffeensis (63), Borrelia burgdorferi (16), and Rickettsia spp. (198) were detected using species-specific PCR assays. Out of 403 spleens from rodents and shrews, A. phagocytophilum (20), A. platys (34), E. chaffeensis (127), and Bartonella spp. (24) were detected with species-specific PCR assays. These results suggest that fevers of unknown causes in humans and animals in Korea should be evaluated for infections by these vector-borne microbial pathogens.

Anopheles lindesayi japonicus Yamada is an uncommonly collected mosquito in Korea, and its presence is based upon limited collection data and anecdotal reports in Korean mosquito literature: 45 specimens collected from 15 identified sites. This study reports the collection of 538 specimens from 16 sites as part of the authors' 2004–2007 anopheline surveillance. Larvae were collected from stream margins, stream pools, rock pools, seepage springs, artificial containers, swamps, and ditches and were found in association with seven other culicid species. Inclusion of the authors' data with previous published and unpublished records makes this a comprehensive report on this species in Korea. New province records are reported for this species at Hwacheon and Wonju in Gangwon Province, Mt. Palgong in Daegu Metropolitan, and Chungju and Mt. Worak in Chungcheongbuk Province in the Republic of Korea.

Japanese encephalitis virus (JEV), transmitted by culicine mosquitoes, is endemic throughout much of South-East Asia, extending to the Korean Peninsula. The zoonotic cycle is from large water birds to culicine mosquitoes, with swine as an amplifying host and man as an incidental host. Culex tritaeniorhynchus, the primary JEV vector in the Republic of Korea, populations peak in late August through to early September when most cases of Japanese encephalitis (JE) are reported. Cx. tritaeniorhynchus were observed near the Demilitarized Zone in each of the years that mosquitoes were assayed for JEV. Each year that vector mosquitoes were assayed for JEV, minimum field infection rates (number of JEV positive mosquites/1000 Cx. tritaeniorhynchus assayed) ranged from 0.31 to 3.27. The epidemiology of JE has been recorded in Korea for more than half a century, from 1949 to 2005. During a major epidemic in 1949, there were 5616 cases and 2729 deaths reported, with levels persisting near epidemic levels of 1000 cases annually thereafter until 1969. Following the introduction and government mandated mass immunization in 1971, JE decreased dramatically. Since 1984, 0–6 cases of JE have been reported each year. However, continued evidence of mosquitoes positive for JEV indicates that JE continues to be a civilian and military health threat to immunocompromised persons in Korea, as well as non-immune US soldiers, civilians and their family members.

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.

Adult mosquito surveillance was conducted during 2004 at 29 US military installations and training sites located in six provinces in the Republic of Korea. Adult mosquitoes were collected in New Jersey light traps and Magnet traps from 1 May through 15 October to determine threshold levels to initiate pesticide applications and to identify malaria infection rates at selected army installations and training sites. A total of 89 206 adults (78 454 [87.9%] females and 10 752 [12.1%] males) comprising 20 species (including five members of the Anopheles Hyrcanus Group) and belonging to seven genera were collected. The most common species collected were members of Culex tritaeniorhynchus Giles (49.4%) and Anopheles sinensis Wiedemann complex (39.1%), followed by Culex pipiens Coquillett (6.1%) and Aedes vexans nipponii (Theobald) (4.2%). Trap indices varied widely for species over their range, due in part to geographical distribution and degree of association with urban communities.

Adult mosquito collections using New Jersey light traps and Black-hole light traps were conducted to determine the potential vectors and the relative mosquito infection rates of Dirofilaria immitis and Dirofilaria repens in Gyeonggi and Gangwon Provinces, Republic of Korea, 2005. Dirofilaria spp. were confirmed by polymerase chain reaction (PCR) using species-specific primers for D. immitis and D. repens. Minimum field infection rates (MFIR) [MFIR = (number infected pools/total number of mosquitoes) x 1000] of 12 pools/2059 total number mosquitoes (5.8) and 21 pools (10.1) of the wild caught mosquitoes were positive by PCR for D. immitis and D. repens, respectively. Dual infections of both D. immitis and D. repens were detected by PCR in eight pools (3.9). Anopheles sinensis sensu lato (includes An. sinensis s.s., An. pullus, An. kleini, An. belenrae, and An. lesteri), An. sineroides, Aedes vexans nipponi, Culex pipiens and Armigeres subalbatus were found to be infected and are potential vectors of D. immitis and D. repens in Korea. Infections observed in mosquitoes represent potential health risks for domestic animal and human populations.

A seroepidemiological study of selected rodent-borne diseases (hantavirus [Seoul [SEO] virus], scrub typhus [Orientia tsutsugamushi], murine typhus [Rickettsia typhi], and leptospirosis [Leptospira interrogans]), as part of the U.S. military rodent surveillance and control program, was conducted from 2001 through 2005 at Yongsan Garrison, Seoul, Republic of Korea. Rodents were collected to determine the prevalence of rodent-borne diseases at a U.S. military installation in an urban environment. A total of 1,750 rodents representing three species was collected by using baited live traps (Tomahawk), glue boards, and poison baits (dead rodents observed but not assayed). The Norway rat, Rattus norvegicus (99.8%), accounted for nearly all of the rodents captured/observed. Only three roof rats, Rattus rattus (0.2%), and one house mouse, Mus musculus (0.1%), were collected. R. norvegicus rats were the only rodents that were serologically positive for SEO virus (9.6%), scrub typhus (2.8%), murine typhus (3.8%), and leptospirosis (4.6%). One of six rodents that were positive for SEO virus by immunofluorescent antibody test was positive for SEO virus antigen by reverse transcriptase-polymerase chain reaction. Infection rates for SEO virus, scrub typhus, murine typhus, and leptospirosis varied annually. Rodents were captured from 228 (20.7%) of 1,104 total buildings in Yongsan Garrison. The Yongsan commissary had the highest annual infestation rate (22 rodents per year), followed by Commisky's Club (18 rodents per year). Annual infestation rates were high for food service facilities, which often store perishable food products outdoors for short periods of time, attracting rodent populations; refuse from these facilities provides harborage and food for rodents. The effect of rodent populations outside the boundary of Yongsan Garrison was not determined.

In 2005, adult and larval mosquito surveillance was conducted at selected sites in Korea to associate larval habitats with species distribution of mosquitoes of the Anopheles Hyrcanus Group (An. sinensis, An. lesteri, An. pullus, An. belenrae and An. kleini) and other mosquito species. Anopheles specimens belonging to the Anopheles Hyrcanus Group were identified to species level by molecular confirmation using the internal transcribed spacer (ITS)-2 within nuclear ribosomal (r)DNA. A total of 6644 mosquitoes from resting and light trap collections (4451; 67.0%) and larval collections (2193; 33.0%) comprising 32 species and nine genera (Culex [11], Anopheles [8], Ochlerotatus [5], Aedes [3], Armigeres [1], Coquillettidia [1], Mansonia [1], Tripteroides [1] and Lutzia [1]) were collected. Larval habitats were characterized into 14 categories. Of a total of 4534 Anopheles spp. collected (3766 resting and light trap collections and 768 larval collections), Anopheles sinensis (3194; 70.4%) was the most frequently captured, followed by An. kleini (813; 17.9%), An. pullus (299; 6.6%) and An. belenrae (129; 2.8%). Four species of Anopheles (An. lesteri, An. sineroides, An. koreicus and An. lindesayi) were infrequently collected (

The 65th Medical Brigade and Public Health Command District-Korea, in collaboration with the Migratory Bird Research Center, National Park Research Institute, conducted migratory bird tick surveillance at Sogugul and Gaerin Islands (small rocky bird nesting sites), Jeollanam-do (Province), Republic of Korea (ROK), on 30 July and 1 August 2009. Breeding seabirds captured by hands in their nesting burrows were banded, identified to species, and carefully examined for ticks during the nesting season. A total of 9 Ornithodoros sawaii larvae were removed from 4 adult Hydrobates monorhis (Swinhoe’s storm petrel). The identification of the larvae of O. sawaii collected from migratory seabirds were molecularly confirmed using mitochondrial 16S rDNA primer sets.

Deer serve as reservoirs of tick-borne pathogens that impact on medical and veterinary health worldwide. In the Republic of Korea, the population of Korean water deer (KWD, Hydropotes inermis argyropus) has greatly increased from 1982 to 2011, in part, as a result of reforestation programs established following the Korean War when much of the land was barren of trees. Eighty seven Haemaphysalis flava, 228 Haemaphysalis longicornis, 8 Ixodes nipponensis, and 40 Ixodes persulcatus (21 larvae, 114 nymphs, and 228 adults) were collected from 27 out of 70 KWD. A total of 89/363 ticks (266 pools, 24.5% minimum infection rate) and 5 (1.4%) fed ticks were positive for Anaplasma phagocytophilum using nested PCR targeting the 16S rRNA and groEL genes, respectively. The 16S rRNA gene fragment sequences of 88/89 (98.9%) of positive samples for A. phagocytophilum corresponded to previously described gene sequences from KWD spleen tissues. The 16S rRNA gene fragment sequences of 20/363 (5.5%) of the ticks were positive for A. bovis and were identical to previously reported sequences. Using the ITS specific nested PCR, 11/363 (3.0%) of the ticks were positive for Bartonella spp. This is the first report of Anaplasma and Bartonella spp. detected in ticks collected from KWD, suggesting that ticks are vectors of Anaplasma and Bartonella spp. between reservoir hosts in natural surroundings.

Tabanid flies were surveyed using New Jersey light traps and Mosquito Magnet® traps at US Army installations and training sites in the northern part of Gyeonggi Province, Republic of Korea. A total of 344 tabanid flies, comprising 14 species and 5 genera, were collected from June to August during 2003-2004. Dominant species were Chrysops vanderwulpi (57.3%), Haematopota sinensis (29.1%), Haematopota koryoensis (4.4%) and Tabanus mandarinus (2.3%). Mosquito Magnet traps that generated CO2through the combustion of propane gas were nearly 6 times more effective in collecting tabanid flies than New Jersey light traps. Based on Mosquito Magnet trap collections, peak populations occurred from mid-June to early July.

Rickettsiae are associated with a diverse range of invertebrate hosts. Of these, mosquitoes could emerge as one of the most important vectors because of their ability to transmit significant numbers of pathogens and parasites throughout the world. Recent studies have implicated Anopheles gambiae as a potential vector of Rickettsia felis. Herein we report that a metagenome sequencing study identified rickettsial sequence reads in culicine mosquitoes from the Republic of Korea. The detected rickettsiae were characterized by a genus-specific quantitative real-time PCR assay and sequencing of rrs, gltA, 17kDa, ompB, and sca4 genes. Three novel rickettsial genotypes were detected (Rickettsia sp. A12.2646, Rickettsia sp. A12.2638 and Rickettsia sp. A12.3271), from Mansonia uniformis, Culex pipiens, and Aedes esoensis, respectively. The results underscore the need to determine the Rickettsia species diversity associated with mosquitoes, their evolution, distribution and pathogenic potential.

The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Gugul and Sogugul Islands, two small, remote, uninhabited islands in southwestern Jeollanam Province, Republic of Korea (ROK) from 2015–2016. Ticks were collected from nest soil/litter of the Ancient Murrelet, Synthliboramphus antiquus, Japanese Murrelet, Synthliboramphus wumizusume, and Swinhoe’s Storm Petrel, Hydrobates monorhis, using Tullgren funnels. A total of 100 Ornithodoros sawaii (25 females, 56 males, 17 nymphs, and 2 larvae) were collected from 2/33 (6.1%) Ancient Murrelet, 3/11 (27.3%) Japanese Murrelet, and 23/94 (24.5%) Swinhoe’s Storm Petrel nest sites. In addition, 3 larvae were collected from Swinhoe’s Storm Petrel nestlings. Ticks were identified morphologically and species determination was confirmed using polymerase chain reaction techniques. This is the first record of O. sawaii collected from nest soil/litter of the Japanese Murrelet during this bird’s nesting season in the ROK.

The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program during 2014–2015 on two small, remote, uninhabited islands, Hong (Gull) Island, southern Gyeongnam Province, and Nan Island, western Chungnam Province, Republic of Korea (ROK). Argasid ticks were collected from Black-tailed Gull (Larus crassirostris) nestlings that had recently died and associated nest soil/litter, and all tick life history stages were identified morphologically. Because morphological keys are unreliable for the identification of adult and nymphal argasid ticks, identifications were confirmed by genotyping using polymerase chain reaction techniques. A total of 29 Ornithodoros capensis larvae and 2 Ornithodoros sawaii larvae were collected from 4 of 7 (57.1%) Black-tailed Gull nestlings that had recently died. An additional five O. capensis (2 males, 1 nymph, and 2 larvae) were collected from nest soil/litter. Only O. sawaii larvae (2/41, 4.9%) were collected from dead Black-tailed Gull nestlings on Nan Island. This is the first report of O. capensis from these seabird breeding islands.

The 65th Medical Brigade and Medical Department Activity-Korea, in collaboration with the Migratory Birds Research Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Chilbal Island during 2016. Chilbal Island is a small, remote, uninhabited government-protected island in southwestern Jeollanam Province, Republic of Korea (ROK). Ticks were collected from nest soil and litter of the Ancient Murrelet, Synthliboramphus antiquus, using Tullgren funnels. A total of 4 Ixodes ticks (3 male Ixodes uriae and 1 female Ixodes signatus) were collected. The principal hosts of I. uriae are pelagic birds that have a largely circumpolar distribution. Ixodes signatus parasitizes other migratory birds in coastal areas of western North America and eastern Asia. This is the first report of I. uriae from the ROK.

Tick-borne disease surveillance was conducted from March–October 2014 in two southeastern provinces, including three metropolitan areas, in the Republic of Korea (ROK). Three general habitats were surveyed: Grasses (grasses and herbaceous and crawling vegetation), Forests (pine, larch, deciduous, and mixed), and Forests+Grasses. A total of 40,048 ticks (1,480 adults; 24,201 nymphs; 14,367 larvae) belonging to three genera and six species were collected. Haemaphysalis longicornis (84.25%; 33,741) was the most commonly collected tick, followed by Haemaphysalis flava (14.52%; 5,816), Ixodes nipponensis (1.09%; 436), Amblyomma testudinarium (0.07%; 27), Haemaphysalis phasiana (0.06%; 23), and Ixodes turdus (0.01%; 5). Overall, adult ticks accounted for only 3.70% of all ticks collected, while nymphs and larvae accounted for 60.43% and 35.87%, respectively. The proportion of H. longicornis nymphs was highest beginning in March (99.51%), slowly declined through July (82.01%) and then rapidly declined to a low in October (6.45%). Large increases in the proportion of H. longicornis larvae were observed in August (42.05%), September (84.19%) and October (93.55%) following increased numbers of adults collected in June (4.20%), July (17.99%) and August (9.79%). Haemaphysalis flava adults and nymphs were commonly collected from April–May and October, while larvae were first collected from July, with peak numbers collected in August and low numbers collected during September–October. The proportion of I. nipponensis adults was highest in March (75.34%), declined to a low in July (0%), and then increased in September (60.00%) and October (90.32%). Larvae were collected only in August–September and accounted for 64.29% and 20.00% of all I. nipponensis collected during those months. Similar proportions of males and females of H. flava (51.47% and 48.53%, respectively) were collected from all habitats, while significantly more I. nipponensis males (62.20%) were collected than females (37.80%). Conversely, the proportion of H. longicornis females (80.00%) collected was significantly higher than for males (20.00%). Overall, the mean number of ticks collected/hr of collection for all habitats was 156.06/hr of collection. Similar numbers were collected/hr for Forests (172.61) and Grasses (168.64), while lower numbers were collected/hr for Forests+Grasses (128.12).

A survey was conducted to determine the distribution and prevalence of Toxoplasma gondii and Babesia microti infections in small mammals captured in Gyeonggi and Gangwon Provinces, Republic of Korea (ROK). The serological prevalence of T. gondii (ELISA) and B. microti (IFAT) was 2.3% (15/667) and 2.1% (14/667), respectively. DNA extracts from small mammal heart tissues were screened by PCR for T. gondii and B. microti targeting regions of the GRA5 gene and the 18S rRNA and β-tubulin genes, respectively. Only 0.17% (1/578) of Apodemus agrarius was positive of T. gondii by PCR, while 0.52% (3/578) was positive of B. microti. All other small mammal species [Micromys minutus (16), Mus musculus (3), Myodes regulus (22), Microtus fortis (6), and Crocidura lasiura (42)] were negative for both T. gondii and B. microti. Based on sequence polymorphism and phylogenetic analysis, T. gondii closely aligned with Type I, a highly virulent strain, while B. microti positive samples closely aligned with US-type B. microti and others observed in the ROK, Russia, and Japan. These results indicate that A. agrarius is a reservoir for both T. gondii and B. microti in the ROK.

Biting midges (Culicoides: Ceratopogonidae) were collected by Mosquito Magnet® traps at the Neutral Nations Supervisory Commission (NNSC) camp and Daeseongdong village inside the demilitarized zone (DMZ) and near the military demarcation line (MDL) separating North and South Korea and at Warrior Base (US Army training site) and Tongilchon 3 km south of the DMZ in northern Gyeonggi Province, Republic of Korea (ROK), from May-October 2010-2012, to determine their seasonal distributions. A total of 18,647 Culicoides females (18,399; 98.7%) and males (248; 1.3%) comprising 16 species were collected. Overall, the most commonly collected species was Culicoides nipponensis (42.9%), followed by C. erairai (29.2%), C. punctatus (20.3%), C. arakawae (3.3%), C. pallidulus (1.8%), and C. circumscriptus (1.4%), while the remaining 10 species accounted for only 1.1% of all Culicoides spp. collected. The seasonal distribution of C. nipponensis was bimodal, with high numbers collected during May-June and again during September. C. erairai was more frequently collected during June-July, followed by sharply decreased populations from August-October. C. punctatus was collected in low numbers from May-September with high numbers collected during October. C. erairai was predominantly collected from the NNSC camp (85.1% of all C. erairai collected) located adjacent to the MDL at Panmunjeom in the northernmost part of Gyeonggi-do (Province), while other sites yielded low numbers of specimens.

As part of the 65th Medical Brigade tick-borne disease surveillance program to determine the abundance, geographical and seasonal distributions, and tick-borne pathogens present in the Republic of Korea, dragging and sweeping methods were compared to determine their efficiency for collecting ticks in grass and deciduous, conifer, and mixed forest habitats at military training sites and privately owned lands in northern Gyeonggi Province near the demilitarized zone from April-October, 2004-2005. Three species of Ixodid ticks, Haemaphysalis longicornis, Haemaphysalis flava, and Ixodes nipponensis, were collected. Overall, H. longicornis adults and nymphs were most frequently collected from grass and deciduous forest habitats, accounting for 98.2 and 66.2%, respectively, of all ticks collected. H. flava adults and nymphs were most frequently collected from conifer and mixed forests, accounting for 81.6, and 77.8%, respectively, of all ticks collected. I. nipponensis adults and nymphs accounted for 9.3% of all ticks collected from mixed forests, were less commonly collected from deciduous (4.1%) and conifer (4.1%) forests, and infrequently collected from grass habitats (0.9%). Overall, there were no significant differences between dragging and sweeping methods for the three species when the areas sampled were similar (sweeping = 2 x the area over the same transect). Adults and nymphs of H. longicornis were most commonly collected from April-August, while those of H. flava and I. nipponensis were most commonly collected during April-July and again during October. Larvae of all three species were most frequently observed from July-September.

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.

The 65th Medical Brigade and Public Health Command District-Korea, in collaboration with the Migratory Birds Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Chilbal Island, a small, remote, uninhabited island in southwestern Jeollanam Province, Republic of Korea (ROK), during 2014–2015. Ticks were collected by dragging vegetation and from nest soil and litter of the Ancient Murrelet, Synthliboramphus antiquus, and Swinhoe’s Storm Petrel, Hydrobates monorhis, using Tullgren funnels. A total of 115 ticks belonging to three genera and three species were collected. Ornithodoros sawaii (98.3%, 113 ticks) was the most frequently collected tick species, followed by Ixodes signatus (0.9%, 1 nymph) collected from nest soil and litter, and Haemaphysalis flava (0.9%, 1 male) collected by tick drag.

Tick surveillance of migratory birds was conducted during 2009 on Hong Island (Hong-do), Jeonnam Province, Republic of Korea. A total of 16/102 (15.8%) species of birds captured by mist net for banding were infested with ticks. A total of 143 ticks belonging to two genera and seven species— Ixodes turdus (96 ticks), Haemaphysalis flava (17), Haemaphysalis longicornis (12), Ixodes nipponensis (10), Haemaphysalis aborensis (3), Haemaphysalis hystricis (3), and Haemaphysalis doenitzi (2)—were collected from 16 bird species representing eight genera. New country and host records are provided for three uncommonly collected tick species: H. hystricis (3 nymphs; Turdus hortulorum and Zoothera dauma ), H. aborensis (3 nymphs; Turdus pallidus ), and H. doenitzi (1 male, 1 nymph; T. pallidus and Turdus naumanni ). Most ticks (124/143; 86.7%) were collected from birds on their northward spring (March–May) migration from Southeast Asia to their breeding grounds in northeastern Asia.

Tick-borne disease surveillance was conducted monthly at different sites in four southwestern provinces of the Republic of Korea (ROK) from April–October 2013. Three general habitats were surveyed: grasses (grasses and herbaceous and crawling vegetation), forests (pine, larch, deciduous, and mixed), and forests+grasses. A total of 27,029 ticks (1,534 adults; 11,755 nymphs; 13,740 larvae) belonging to three genera and five species were collected. Haemaphysalis longicornis (64.76%; 17,504) was the most commonly collected tick, followed by Haemaphysalis flava (29.22%; 7,899), Ixodes nipponensis (5.83%; 1,575), Amblyomma testudinarium (0.17%; 46), and Haemaphysalis phasiana (0.02%; 5). Overall, adult ticks accounted for only 5.68% of all ticks collected, while nymphs and larvae accounted for 43.49% and 50.83%, respectively. Haemaphysalis longicornis nymphs were commonly collected from April–June, followed by increased numbers of adults from June–August, and large numbers of larvae from August–September, while low numbers of all stages were collected during October. Haemaphysalis flava adults and nymphs were commonly collected from April–June and September–October, while large numbers of larvae were collected from July–August. Although fewer I. nipponensis were collected, seasonal developmental stage patterns followed those of H. flava. Similar proportions of males (47.96%) and females (52.04%) of H. flava were collected. However, the proportion of H. longicornis females (85.83%) collected was significantly higher than for males (14.17%), while the proportion of I. nipponensis males (57.62%) was significantly higher than for females (42.38%). Overall, the mean number of ticks collected/hour of collection was highest for forests+grasses (108.54), followed by grasses (97.28) and forests (66.64).

We used epidemiological data and indirect fluorescent antibody tests to determine the Hantaan virus (HTNV) antibody-positive (Ab+) prevalence in small mammals captured at firing point 10 (FP-10) and firing point 60 (FP-60), Gyeonggi Province, near the demilitarized zone, Republic of Korea (ROK), from 2001 to 2005. We used these data, combined with the partial M segment amplified from HTNV recovered from lung tissues of Apodemus agrarius, to clarify the genetic diversity and phylogenetic relationships among HTNV strains in the ROK. Of the eight species of rodents and one insectivore species captured, A. agrarius accounted for 93.4% and 88.5% at FP-10 and FP-60, respectively. Only two species of rodents, A. agrarius and Micromys minutus, were HTNV Ab+. The overall HTNV Ab+ prevalence for A. agrarius captured at FP-10 and FP-60 was 23.3% (121/520) and 14.5% (94/647), respectively. The hantaviral reverse transcription-polymerase chain reaction-positive rate of Ab+ A. agrarius was 74.2% (167/215), and the phylogenetic trees, based on the 269-nucleotide G2-encoding M segment, demonstrated that HTNV strains from FP-10 and FP-60 were distantly segregated from HTNV of other geographic regions in Korea and China. These data are useful in the development of risk reduction strategies for the prevention of hantavirus infections among military personnel, especially during training or the event of hostilities, and civilian populations.

In response to a hemorrhagic fever with renal syndrome case in November 2000, a seasonal rodent-borne disease surveillance program was initiated at Dagmar North Training Area (DNTA), Gyeonggi Province, Republic of Korea. From April 2001-December 2005, 1,848 small mammals were captured. Apodemus agrarius accounted for 92.5%, followed by Mus musculus (3.6%), Crocidura lasiura (2.1%), and Microtus fortis (1.1%). Three species of rodents were found to be antibody-positive (Ab+) for Hantaan virus (HTNV): A. agrarius (22.3%), M. musculus (9.1%), and M. fortis (5.0%). Ab+ rates for A. agrarius increased with increasing weight (age), except for those weighing10 g. The peak HTNV transmission period in Korea coincided with the peak reproductive potential of A. agrarius during the fall (August/September) surveys. HTNV strains from DNTA were distinct from HTNV strains from the People's Republic of China. From these studies, more accurate risk assessments can be developed to better protect personnel from rodent-borne diseases.

A total of 180 larval collection sites (e.g., rice paddies, marshes, ground pools, ponds, stream margins, and irrigation and drainage ditches) was surveyed within a 2 km radius from Warrior Base training area, 5 km south of Panmunjeom (Joint Security Area, demilitarized zone), Gyeonggi Province, Republic of Korea (ROK), from May through October, 2007 to characterize larval habitat distributions of members of the Anopheles Hyrcanus Group (An. sinensis, An. lesteri, An. pullus, An. belenrae, An. kleini, and An. sineroides). A total of 5,859 anopheline larvae was collected from 84.4% of the sites surveyed, of which 4,071 were identified to species by polymerase chain reaction (PCR) using the ribosomal DNA internal transcribed spacer 2 (rDNA ITS2). Anopheles sinensis (52.6%) was the most frequently collected, followed by An. kleini (29.4%), An. sineroides (9.8%), An. pullus (6.7%), An. belenrae (1.1%), and An. lesteri (0.5%). Anopheles pullus and An. kleini were collected in greater proportions in May and from May - July, respectively. Few An. sinensis were collected from May - June, but it was the predominant species collected by August, and accounted for80% of all larvae from September - October. Anopheles kleini was found in all habitats sampled; however, it was collected most frequently in young growth rice paddies, while An. sinensis was collected more frequently in mature and post-harvest paddies. Anopheles pullus was associated with pre-cultivated rice paddies, including water-filled tire ruts left from the previous fall's harvest.

Fleas were collected from live-captured small mammals to identify flea-borne pathogens, host associations, and seasonal prevalence of flea species, as part of the 65th Medical Brigade rodent-borne disease surveillance program at 20 military installations and training sites, Gyeonggi Province, Republic of Korea, 2005-2007. A total of 1251 fleas were recovered from 2833 small mammals. Apodemus agrarius, the striped field mouse, accounted for 93.1% (2,637/2,833) of all small mammals captured, followed by Crocidura lasiura (3.1%), Mus musculus (1.3%), Microtus fortis (0.7%), Myodes regulus (0.7%), Micromys minutus (0.5%), Rattus norvegicus (0.4%), Tscherskia triton (0.1%), Apodemus peninsulae (0.1%), Rattus rattus (0.1%), and Mogera robusta (0.1%). A total of 6/11 species of mammals captured were infested with fleas with infestation rates ranging from a high of 26.3% (A. agrarius and M. regulus) to a low of 5.3% (M. fortis). Flea indices among infested mammals were highest for R. norvegicus (2.50), followed by C. lasiura (2.20), A. agrarius (1.71), M. regulus (1.20), M. musculus (1.0), and M. fortis (1.0). The predominant flea species collected were Stenoponia sidimi (56.5%), followed by Ctenophthalmus congeneroides (38.3%) and Rhadinopsylla insolita (3.9%). The minimum field infection rates [number of positive pools/total number of fleas (600)] for Rickettsia typhi and for Rickettsia felis were 1.7% and 1.0%, respectively.

This study sought to identify seasonal and environmental determinants of scrub typhus, murine typhus, and leptospirosis in small mammals trapped at Dagmar North training area, Gyeonggi Province, South Korea.Small mammals received titer assays to the aforementioned diseases. Logistic regression analyses were conducted to determine whether associations existed between risk of small-mammal infection and independent variables such as season of capture, habitat, small-mammal species, and sex.Murine typhus was not detected among the animals assayed. Risk of scrub typhus infection was associated with season, habitat, and small-mammal species. Risk of leptospirosis infection was associated with season and habitat.These findings indicate determinants of infection exist for scrub typhus and leptospirosis at this training site. This information can be used for developing appropriate preventive medicine plans and coordinating troop activity during periods of reduced exposure decreasing the likelihood of disease transmission to humans.

A total of 1,498 small mammals (rodents and insectivores), including Apodemus agrarius (n = 1,366), Crocidura lasiura (54), Mus musculus (32), Micronytus fortis (28), Eothenomys regulus (9), Micronys minutes (6), and Cricetulus triton (3), were live-trapped in Gyeonggi-do (Province) (Paju-si, Pocheon-gun, and Yeoncheon-gun) near the demilitarized zone (DMZ) from December 2004 to September 2005. A. agrarius was found to be infected with 3 species of echinostomes (Echinostoma hortense, Echinostoma cinetorchis, and Euparyphium murinum), while C. lasiura was infected with 1 species (Echinochasmus japonicas) of echinostome. Other mammals were free from echinostome infections. Total 16 E. hortense were detected in 7 (0.5%) mice, 9 E. cinetorchis from 5 (0.4%), and 3 E. murinum from 2 (0.1%) out of 1.366 A. agrarius examined. E. japonicus was found only in 1 (1.9%; total 3 specimens) C. lasiura. These results demonstrate that A. agrarius and C. lasiura, inhabiting near the DMZ of Gyeonggi-do serve as the natural definitive hosts for several species of echinostomes, although their infection rates are low. This is the first record of natural infections of A. agrarius with E. cinetorchis and C. lasiura with E. japonicus in the Republic of Korea.

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 ). Robust gene amplification techniques have now uncovered several genetically distinct hantaviruses from shrews in widely separated geographic regions. Here, we report the characterization of a newly identified hantavirus, designated Imjin virus (MJNV), isolated from the lung tissues of Ussuri white-toothed shrews of the species Crocidura lasiura (order Soricomorpha, family Soricidae, subfamily Crocidurinae) captured near the demilitarized zone in the Republic of Korea during 2004 and 2005. Seasonal trapping revealed the highest prevalence of MJNV infection during the autumn, with evidence of infected shrews' clustering in distinct foci. Also, marked male predominance among anti-MJNV immunoglobulin G antibody-positive Ussuri shrews was found, whereas the male-to-female ratio among seronegative Ussuri shrews was near 1. Plaque reduction neutralization tests showed no cross neutralization for MJNV and rodent-borne hantaviruses but one-way cross neutralization for MJNV and TPMV. The nucleotide and deduced amino acid sequences for the different MJNV genomic segments revealed nearly the same calculated distances from hantaviruses harbored by rodents in the subfamilies Murinae, Arvicolinae, Neotominae, and Sigmodontinae. Phylogenetic analyses of full-length S, M, and L segment sequences demonstrated that MJNV shared a common ancestry with TPMV and remained in a distinct out-group, suggesting early evolutionary divergence. Studies are in progress to determine if MJNV is pathogenic for humans.

The 65 th Medical Brigade and Public Health Command Region-Pacific (Korea), in collaboration with the Migratory Birds Center, National Park Research Institute, conducted a migratory bird tick-borne disease surveillance program on Chilbal Island, a small, remote, uninhabited island in southwestern Jeollanam Province, Republic of Korea (ROK), on 1 and 31 May and 15 September 2014. Ticks were collected from nesting soil and litter of the Ancient Murrelet, Synthliboramphus antiquus , and Swinhoe’s Storm Petrel, Hydrobates monorhis , using Tullgren funnels. A total of 12 Ornithodoros sawaii (2 females, 4 males, and 6 nymphs) were collected from 3/36 (8.3%) S. antiquus and 6/20 (30.0%) H. monorhis nest sites. Ticks were identified morphologically and species determination was confirmed using polymerase chain reaction techniques. This is the first report of the genus O rnithodoros and species O. sawaii from the ROK.

Rodent-borne disease surveillance was conducted at Nightmare Range (NM-R), near the demilitarized zone in northeast Gyeonggi Province, Republic of Korea, to identify hemorrhagic fever with renal syndrome (HFRS) risks for a mountainous high-elevation (500 m) military training site. Monthly surveys were conducted from January 2008-December 2009. A total of 1,720 small mammals were captured belonging to the Orders Rodentia [Families, Sciuridae (1 species) and Muridae (7 species)] and Soricomorpha [Family, Soricidae (1species)]. Apodemus agrarius, the primary reservoir for Hantaan virus (HTNV), accounted for 89.9% (1,546) of all small mammals captured, followed by Myodes regulus (4.0%), Crocidura lasiura (3.9%), Micromys minutus (1.4%), Mus musculus (0.3%), Microtus fortis (0.2%), Apodemus peninsulae (0.2%), Tamias sibiricus (0.1%), and Rattus norvegicus (

In order to investigate the prevalence of tick-borne infectious agents among ticks, ticks comprising five species from two genera ( Hemaphysalis spp. and Ixodes spp.) were screened using molecular techniques. Ticks (3,135) were collected from small wild-caught mammals or by dragging/flagging in the Republic of Korea (ROK) and were pooled into a total of 1,638 samples (1 to 27 ticks per pool). From the 1,638 tick samples, species-specific fragments of Anaplasma phagocytophilum (1 sample), Anaplasma platys (52 samples), Ehrlichia chaffeensis (29 samples), Ehrlichia ewingii (2 samples), Ehrlichia canis (18 samples), and Rickettsia rickettsii (28 samples) were amplified by PCR assay. Twenty-one pooled and individual tick samples had mixed infections of two (15 samples) or three (6 samples) pathogens. In addition, 424 spleen samples from small captured mammals (389 rodents, 33 insectivores, and 2 weasels) were screened for selected zoonotic pathogens. Species-specific DNA fragments of A. phagocytophilum (110 samples), A. platys (68 samples), E. chaffeensis (8 samples), E. ewingii (26 samples), E. canis (51 samples), and Rickettsia sp. (22 samples) were amplified by PCR assay. One hundred thirty small mammals had single infections, while 4, 14, and 21 striped field mice ( Apodemus agrarius ) had mixed infections of four, three, and two pathogens, respectively. Phylogenetic analysis based on nucleotide sequence comparison also revealed that Korean strains of E. chaffeensis clustered closely with those from China and the United States, while the Rickettsia (rOmpA) sequences clustered within a clade together with a Chinese strain. These results suggest that these agents should be considered in differential diagnosis while examining cases of acute febrile illnesses in humans as well as animals in the ROK.