• Parasites, Hosts and Diseases
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• v.30 no.4
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• pp.341-348
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• 1992

Because no reference on trombiculid mites (Acarina: Trombiculidae) in Cheju Island where tsutsugamushi disease is highly endemic had been available, studies on trombiculid mites in Cheju Island were implemented during the period of August 1991-Apil 1992, and the results obtained are summarized as follows: (1) The species and numbers of the field rodents collected were 143 Apodemus agrarius chejuensis (92.3%), 11 Crocidura lasiura (7. l%) and 1 Micromys minutus (0.6%) From total 12,075 chiggers harvested, 9 species of 4 genera in Trombiculidae were identified. (2) The predominant species through all seasons was 1. setum (43.3%), followed by 1. orientale (27.4%) and 1. scutellare (26.6%). However, in autumn when the most cases of tsutsugamushi disease occur, 1. scutellere was prominently predominant, having 79.8% of the collected chiggers. (3) Among 1,1421. scutellare examined for Rickettsia tsutsugpmushi by means of IFA test, 6 individuals were found positive showing 0.5% of infection rate. This is the first finding that 1. scutellere is the second vector species of tsutsugamushi disease in Korea. (4) Antibody positive rate of A. agrarius chejuensis sera were 31.2% (44/139), and 1 M. minutes serum was also found positive. The seropositive rates by season were not so significantly different. Key words: Tsutsugamushi disease, epidemiology, vector species, Cheju Island, Korea.

• Pediatric Infection and Vaccine
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• v.8 no.2
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• pp.160-167
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• 2001

Purpose : To assess the immunogenicity, safety, and tolerability of hepatitis A vaccine ($VAQTA^{TM}$) in healthy children and adolescents. Methods : Eligible subjects aged 2 to 17 years received 25 U/0.5 mL of $VAQTA^{TM}$ intramuscularly at 0 and 24 week schedule. Bleeds were obtained prior to vaccination and 4 weeks after the second dose to ascertain serostatus. To detect antibody to HAV after vaccination with an inactivated HA vaccine, a modification of the $Abbott^{(R)}$ HAVAB kit was used. Sample with titers ${\geq}10$ mIU/mL were considered seroconverted. Adverse experiences were monitored. Results : 102 subjects(54 male, 48 female) were enrolled. The mean age was $6.8{\pm}3.5$ years. Two subjects were seropositive, two were lost of follow up. 88 subjects were available for a per protocol analysis and 90 for all subjects with serology after the second dose, and ten withdral. All subjects(95% CI, 94.8~100) seroconverted. Geometric mean titers was 7,991.1(95% CI, 6,481.1~9,852.7) with very little difference in per protocol analysis and all subjects analysis. Adverse experiences to $VAQTA^{TM}$ were generally mild and transient. Conclusion : The pediatric two-dose regimen of $VAQTA^{TM}$ was found to be highly immunogenic, generally well tolerated and resulted in 100% seroconversion. Regarding Korea is in transition from a high to low risk region resulting in a paradox increase of clinical disease and disease burden, routine vaccination should be considered in order to control hepatitis A effectively.

• Pediatric Infection and Vaccine
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• v.12 no.2
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• pp.108-113
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• 2005

Purpose : Human herpsevirus 8(HHV-8), a gamma herpsevirus, was initially identified from Kaposi sarcoma(KS) lesions and has been known to be associated with several malignancies including Kaposi sarcoma. HHV-8 seroprevalence is variable by different geographic areas and populations. The prevalence of HHV 8 infection in Korean children is unclear. So, we investigated the prevalence of HHV-8 specific antibodies in healthy children in Seoul, Korea. Methods : Sera were obtained from 112 children(age 1~15 years, 64 males and 48 females) who visited our hospital for routine health checkup and used for investigating sero-prevalence of anti-HHV-8 antibodies. An indirect immunofluorescent assay was used to detect the IgG antibodies to the lytic viral antigen(Biotrin, Dublin, Ireland). A peptide mix ELISA kit was used to detect the IgG antibodies to peptides specific for HHV-8 open reading frame (ORF)(Biotrin, Dublin, Ireland). Results : Of 112 children, 4 children younger than 6 years of age were seropositive to HHV-8[all 4(3.5%) were positive by IFA and 2(1.8%) were positive by ELISA]. Conclusion : These results suggest that the prevalence of antibody to HHV 8 in children in Korea is very low.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.67-73
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• 2008

Porcine reproductive and respiratory syndrome (PRRS) is the most economically important viral infectious disease in pig populations worldwide. This study was conducted to better understand the epidemic and dynamics of PRRS virus (PRRSV) on each farm and to evaluate the risk of PRRSV infection in Korea. Interviews with pig farmers were carried out to obtain PRRS vaccination programmes in 60 pig farms throughout Korea. Blood samples were also collected from the 59 pig farms to investigate outbreak patterns of each farm. Vaccination against PRRS was performed in 16.7% farms for breeding pigs and 8.3% of farms for nursery pigs. According to the seroepidemiological analysis, 56 (94.9%) out of 59 farms were considered to be affected by PRRSV infection. The results revealed that 68.9% of sows tested were seroconverted and interestingly, gilt herds had the highest seropositive rate (73%), suggesting that gilts may play a key role in PRRSV transmission in sow herds. Among the PRRS-affected piglet herds, 33 (55.9%), 14 (23.7%) and 6 (10.2%) farms were initially infected with PRRSV during the weaning, suckling and nursery period, respectively. It seems likely, therefore, that PRRSV infection predominantly occurs around the weaning period in piglet herds. Based on antibody seroprevalence levels in both sow and piglet groups, we were able to classify patterns of PRRSV infection per farm unit into 4 categories; category 1 (stable sow groups and non-infected piglet groups), category 2 (unstable sow groups and non-infected piglet groups), category 3 (stable sow groups and infected piglet groups), and category 4 (unstable sow groups and infected piglet groups). Our data suggested that 43 (72.9%) farms were analysed to belong to category 4, which is considered to be at high-risk for PRRS outbreak. Taken together, our information from this study will provide insight into the establishment of an effective control strategy for PRRS on the field.

• Clinical and Experimental Pediatrics
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• v.52 no.9
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• pp.1053-1058
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• 2009

Cytomegalovirus (CMV) is one of the most commonly encountered viral pathogens in newborn infants and is found in 0.3-2.4% of all live births. It has been demonstrated that 40-96% of seropositive mothers shed the virus via their breast milk. Breast milk containing CMV can cause almost one-third of CMV infections occurring in infants. A case of postnatal CMV infection in an extremely premature infant (gestational age $24^{+5}$ weeks, birth weight 750 g) transmitted via breast milk is presented. For neonatal intensive care unit (NICU) management of severe thrombocytopenia, anemia, and sepsis syndrome, the infant received repeated transfusions of platelets; intravenous (IV) immunoglobulins; and gamma- irradiated, filtrated packed red cells and was fed her mother's breast milk since the second week of life. CMV infection was diagnosed with positive CMV immunoglobulin M (IgM) and positive urine CMV culture at the second month of life. Considering the negative CMV IgM and urine CMV culture at birth, postnatally-acquired CMV infection was suspected and confirmed with completely identical nucleotide sequence alignments of the infantile blood isolate and the maternal breast milk isolate. To our knowledge, this is the first case of proven postnatal CMV infection transmitted via breast milk in an extremely premature infant in Korea.

• Korean Journal of Veterinary Service
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• v.36 no.1
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• pp.7-13
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• 2013

Bovine viral diarrhea virus (BVDV) is one of the most important disease viruses in cattle that can cause severe economical losses due to decreased fertility, abortion, diarrhea, and respiratory symptoms. Therefore, this study was aimed to investigate prevalence of BVDV infection (Transiently infection, Persistently infection) in dairy cattle in Gyeongnam southern area, Korea and use this data as the basis for establishing an eradication program and policy. A total of 44 bulk-tank milk samples (farms) collected in milk collecting center were tested for BVDV antibody using an ELISA. As the result, out of a total of 44 bulk-tank milk samples (farms), 38 (86.4%) samples were BVDV antibody positive. Blood samples (17 farms, n=543) were collected from BVDV antibody positive farms in bulk-tank milk, tested for BVDV antigen with ELISA and PCR. BVDV infected farms were 47% (8/17) and BVDV infected head were 2.2% (12/543). Persistently infected cattle (PI) were detected at 6 (35.3%) farms out of 17 farms and a total of 6 (1.1%) out of 543 head of cattle were identified as PI. The seropositive of BVDV antibody at farms and head were 100% (17/17) and 49.45% (91/184), respectively. The seroprevalence of BVDV antibody in PI infected farms (67.35%) much higher than that of BVDV antibody in transiently infected cattle (TI) infected farms (45%) and uninfected farms (34.48%). For eradication of BVDV infection in cattle populations, First of all, we should remove PI and need vaccination.

• Korean Journal of Veterinary Research
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• v.26 no.1
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• pp.87-92
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• 1986

The present surveys were conducted in attempts to investigate the health situation of horses in Korea through mass-screening the samples serologically, bacteriologically and clinically. A total of 575 horses were sampled randomly, comprising 126 from the Korean Horse Affairs Association, 288 from the Korean Equestrian Federation and 161 from the Jeju ponies. Each of the samples taken was tested for diagnoses of 18 horse diseases including African horse sickness. Summarised below are the results obtained from this surveys. 1. From results of the serological survey it is evident that Korea is currently free from African horse sickness, dourine, glanders, vesicular stomatits, equine piroplasmosis, equine viral arteritis, Venezuelan encephalomyelitis and contagious equine metritis. Constant vigilence with strengthened quarantine measures is thus vital for maintaining freedom of any those diseases in Korea. 2. No clinical case was observed with any of signs or symptoms of infectious lymphangitis, anthrax and infestations with ringworm, mange or scab. However, continuous follow-up is required for establishing the evidence of no occurrence of the diseases in Korea. 3. One case of seropositive to equine infectious anemia may fully justify systematic and regular testings for the whole population of horse in Korea. 4. It is manifested that equine rhinopneumonitis, Japanese encephalitis and Getah virus infection are well established in Korea, together with the presence of equine infectious abortion(Salmonella abortus equi). This strongly entails preventive precautions before entry into Korea for the horses participating in the 1986 Asian Games and the 1988 Seoul Olympics.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.56-62
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• 2000

Purpose: The aim of this study was to evaluate the efficacy and histologic changes of interferon-alfa therapy on chronic hepatitis B virus infection in children. Patients and Methods: Thirty five children aged 3~16 years who were seropositive for HBV DNA, HBsAg and HBeAg were enrolled. Interferon-alfa 2a ($3.4\;MU/m^2$) were given for 6 months. Serologic markers of viral replication was evaluated 1 year after therapy. Post treatment liver biopsy was performed in 18 patients who showed serologic response. Results: Serum HBeAg and viral DNA became negative in 22 (63%) of treated children at 12 months after therapy. Serum aminotransferase levels normalized in all of the responders and HBsAg became negative in one responder. Horizontal transmission, serum aminotransferase levels more than twice normal, and active inflammation on liver biopsy were predictive factors for response to interferon therapy. Periportal piecemeal necrosis, lobular activity, portal inflammation, fibrosis, and total histologic activity index were reduced in responders. Conclusion: In children with chronic hepatitis B, interferon alfa promotes loss of viral replication and improves aminotransferase. Serologic response is associated with improvement in hepatic histology.

• Journal of Veterinary Clinics
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• v.27 no.3
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• pp.268-272
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• 2010

South Korea is susceptible to foreign diseases due to its high rate of livestock importation. The purpose of this study was to investigate the infectious conditions of contagious disease of horses imported into South Korea from other countries. The horses were tested for contagious equine metritis (CEM), equine infectious anemia (EIA), equine piroplasmosis (EP), equine viral arteritis (EVA), vesicular stomatitis (VS), dourine, and glanders. The prevalence of these infectious diseases in 6,650 horses imported from 24 countries between 2003 and 2008 was reviewed by the National Veterinary Research and Quarantine Service. Seropositive results were found for EIA, EP, EVA, dourine and glanders: 3/6,189 serum samples tested were EIA-positive, 37/6,005 samples tested by complement fixation (CF) were EP-positive, 28/6,043 samples tested by virus neutralization (VN) were EVA-positive, 4/2,071 serum samples tested by CF were positive for dourine, and 4/1,950 samples tested by CF were positive for glanders. No contagious equine metritis or vesicular stomatitis was detected. In total, 76/6,650 imported horses tested positive for an infectious disease. Notably, 4/6 sera (66.6%), all taken from horses imported from Tanzania, were positive for glanders. This is the first report of glanders infection in horses from Tanzania since 1996.

• The Journal of Korean Society of Virology
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• v.28 no.3
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• pp.275-285
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• 1998

Based on the geographic range and distribution of its rodent reservoir host, the European common vole (Microtus arvalis), Tula virus is likely to be widespread throughout Eurasia. Tula virus-infected voles have been captured in Central Russia, Austria, Czech and Slovak Republics, and the former Yugoslavia. Although serologic evidence for Hantaan (HTN) or Seoul (SEO) virus infection can be found in the vast majority of the more than 300 cases of hemorrhagic fever with renal syndrome (HFRS) occurring annually in Korea, approximately 4% of Korean patients with HFRS show a more than 4-fold higher antibody titer to Puumala (PUU) virus than to HTN or SEO virus by double-sandwich IgM ELISA, suggesting the existence of pathogenic Puumala-related hantaviruses in Korea. To further define the geographic distribution and genetic diversity of Tula virus in Eurasia and to investigate the existence of previously unrecognized Microtus-borne hantavirus in Korea, arvicolid rodents were captured in Lodz, Poland in 1995 and in Yunchon-kun, Kyungki-do during April to May, 1998. In addition, sera from 18 Korean HFRS patients who showed higher (or the same) antibody titer to Tula virus than HTN and SEO viruses were examined for hantavirus RNA by RT-PCR. Hantaviral sequences were not detected in any of the 18 patients or in 35 reed voles (Microtus fortis) in Korea. Alignment and comparison of a 208-nucleotide region of the S segment, amplified from lung tissues of two hantavirus-seropositive Marvalis captured in Poland, revealed $80.8{\sim}83.2%$ sequence similarity, respectively, with Tula virus strains from Central Russia and the Czech and Slovak Republics. Phylogenetic analysis indicated that the newfound Tula virus strains from Poland were closely related to other Tula hantaviruses from Eurasia.