• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.818-822
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• 1998

The persistence of porcine epidemic diarrhea virus(PEDV) infection was demonstrated in 7 swine farms employing continuous pig flow management even after seasonal outbreaks. Clinically, sporadic postweaning diarrhea was a major concern in those farms. Subsequently circulatory antibody detection using serum neutralizing test made useful for confirmation of PEDV persistent infections. The persistence of PEDV in the premise might have induced recurrence over the period of time.

• Journal of Veterinary Science
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• v.24 no.4
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• pp.58.1-58.25
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• 2023

Porcine epidemic diarrhea virus (PEDV) has posed significant financial threats to the domestic pig industry over the last three decades in South Korea. PEDV infection will mostly result in endemic persistence in the affected farrow-to-finish (FTF) herds, leading to endemic porcine epidemic diarrhea (PED) followed by year-round recurrent outbreaks. This review aims to encourage collaboration among swine producers, veterinarians, and researchers to offer answers that strengthen our understanding of PEDV in efforts to prevent and control endemic PED and to prepare for the next epidemics or pandemics. We found that collaboratively implementing a PED risk assessment and customized four-pillar-based control measures is vital to interrupt the chain of endemic PED in affected herds: the former can identify on-farm risk factors while the latter aims to compensate for or improve weaknesses via herd immunity stabilization and virus elimination. Under endemic PED, long-term virus survival in slurry and asymptomatically infected gilts ("Trojan Pigs") that can transmit the virus to farrowing houses are key challenges for PEDV eradication in FTF farms and highlight the necessity for active monitoring and surveillance of the virus in herds and their environments. This paper underlines the current knowledge of molecular epidemiology and commercially available vaccines, as well as the risk assessment and customized strategies to control PEDV. The intervention measures for stabilizing herd immunity and eliminating virus circulation may be the cornerstone of establishing regional or national PED eradication programs.

• Journal of Veterinary Clinics
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• v.20 no.2
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• pp.150-154
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• 2003

A disease with severe diarrhea occurred in a herd of one thousand, 1-week-old piglets in Chinju, Korea, and was diagnosed as porcine epidemic diarrhea by the detection of N gene of porcine epidemic diarrhea virus (PEDV) from small intestines. A PEDV, named as Chinju99, was also isolated from the intestines after two blind-passages in Vero cells supplemented with trypsin (10 ug/ml). and the biological and physicochemical properties of the isolate were characterized. The virion was roughly spherical in shape and had spike peplomers on its outer surface. The virus exhibited cytopathic effects such as rounding degeneration at initiation of infection and syncytia formation later in Vero cells. The virus was labile to 20% ether and 5% chloroform but stable in acid with pH 4-7 at $4^{\circ}C$. The infectivity of the virus was maintained at $50^{\circ}C$ for 180 min, and the buoyant density of the virus in sucrose was 1.180 g/ml. All biological and physicochemical properties of the virus were typical features of coronaviruses.

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.477-483
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• 2003

Molecular diagnostic techniques have been used to identify porcine epidemic diarrhea virus (PEDV), a causative agent of acute enteritis in swine, but they were difficult to be petformed and time-consuming. To detect PEDV in a rapid and easy way, we developed biotinylated cDNA probe for N gene encoding the nucleoproteins of PEDV. Formalin-fixed and paraffin-embedded tissues from 24 naturally infected pigs were used for the experiment. The ISH produced a positive reaction in all cases. When intestinal tissues were hybridized with PEDV probe, strong signals were seen in the villus enterocytes of the jejunum and ileum. Hybridization signals were also found in the duodenum from one pig and in colon from dnother. In conclusion, ISH with a biotinylated cDNA probe was provided to be a useful diagnostic method for detecting PEDV effectively in routinely processed tissue sections.

• Korean Journal of Veterinary Service
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• v.37 no.2
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• pp.105-110
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• 2014

Porcine epidemic diarrhea virus (PEDV) is the causative agent of porcine epidemic diarrhea (PED) and causes a considerable economic loss in swine industry. In this study, the virucidal efficacy of the disinfectant composed to n-alkyl-dimethyl-benzyl-ammonium chloride (n-ADBAC) was investigated against PEDV. A virucidal efficacy was determined with the viability of PEDV contacted with the disinfectant in Vero cells. The disinfectant and PEDV were reacted on the hard water (HW) or organic matter suspension (OM) condition. On HW condition, PEDV was inactivated with 50 fold dilutions of the disinfectant. When the antiviral effect on OM condition was evaluated, the antiviral activity of the disinfectant showed on 10 fold dilutions against PEDV. As the disinfectant possesses the virucidal efficacy against PEDV, the disinfectant solution can be used to limit the spread of animal viral diseases.

• Korean Journal of Veterinary Research
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• v.54 no.3
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• pp.185-188
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• 2014

Porcine epidemic diarrhea virus (PEDV) strains responsible for recent outbreaks in the United States have been occurring in Mainland Korea since late 2013. Over the past 10 years, PEDV outbreaks have not been reported on Jeju Island. However, in late March of 2014, PEDV re-emerged on Jeju Island and was found to be genetically identical to PEDV strains currently circulating in Mainland Korea. The present study was conducted to provide a better understanding of the epidemiology of PEDV and more effective preventive measures against PED.

• Korean Journal of Veterinary Pathology
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• v.2 no.2
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• pp.107-116
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• 1998

Twelve colostrum-deprived piglets were inoculated oral1y with porcine epidemic diarrhea virus isolated from Korea. The piglets were euthanatized from at 12 hour postinoculation(PI) at 6-hour intervals. At 24 to 36 hours PI, all infected piglets showed severe yellowish to watery diarrhea, dehydration, depression, and anorexia. At necropsy, the intestinal wall looked thin, mesenteric vessels congested, and mesenteric lymph nodes edematous. The histological findings showed marked villous atrophy and fusion, severe degeneration of enterocytes and monomuclear cell infiltration in the lamina propria. On electron microscopy, villous epithelial cells of infected jejunum contained viral particles at 18 hour PI. The viral particles were pleomorphic spheres with a mean diameter of 95∼180nm including 18nm projections.

• Korean Journal of Veterinary Service
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• v.46 no.3
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• pp.193-202
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• 2023

Porcine epidemic diarrhea is an infectious intestinal disease caused by the porcine epidemic diarrhea virus (PEDV). Especially, when suckling piglets are infected, the mortality rate is close to 100%. PEDV is classified into G1 and G2 types based on genetic differences. The G2 type PEDV outbreak in the United States in 2013 was highly pathogenic and contagious, and it has spread worldwide and caused continuous economic losses. Most commercial vaccines used are G1 type vaccines, and existing vaccines do not fully protect piglets due to genetic differences. In this study, we evaluated the safety of the newly developed G2 type attenuated HSGP vaccine strain by inoculating it into piglets and testing whether the vaccine virus spreads to the non-vaccinated, negative pigs and whether the vaccine reverts to its virulence during serial passage experiments. Each experiment lasted for 7 days for each passage, and fecal viral titers, clinical symptoms, and weight gain were measured daily. After the experiment, necropsy was performed to measure intestinal virus titer and pathological evaluation. As a result of the first passage, no transmission of the vaccine virus to negative pigs co-housed with vaccinated pigs was observed. In addition, after four consecutive passage experiments, the clinical symptoms and small intestine lesions were gradually alleviated, and no virus was detected in the feces in the fourth passage experiment. Therefore, it was concluded that the vaccine was safe without virulence reversion in accordance with the guidelines of the current licensing authority. However, further studies are needed on the genetic changes and biological characteristics of the mutant virus that occur during successive passages of the attenuated vaccine since the replication and clinical symptoms of the virus increased until the third passage during successive passages of the vaccine virus. Based on this study, it was concluded that virulence reversion and safety evaluation of attenuated vaccines through serial passage in target animals can be useful to evaluate the safety of attenuated viruses.

• Korean Journal of Veterinary Research
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• v.33 no.2
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• pp.249-254
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• 1993

The etiological survey on porcine epidemic diarrhea virus(PEDV) by immunofluorescence antibody test(IFA) showed the positive rusult from the intestines of piglet died from acute diarrhea. The viral agent of PED was also isolated from intestine, which showed positive reaction by immunofluorescence test. After passage in Vero cell, the viral agent was further cloned by plaque purification and designated as KPEDV-9. The immunoblotting analysis using hyperimmune sera and porcine sera revealed the presence of several polypetide bands with molecular weight(M.W.) of 88K, 74K, 70K, 58~54, 54~46K, 44~40K and 33~32K, respectively.

• Journal of the korean veterinary medical association
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• v.29 no.6
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• pp.360-365
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• 1993

Attempts to isolate porcine epidemic diarrhea virus(PEDV) were made by inoculating feces homogenates into Vero cells cultures with trypsin. Cytopathic effects(CPE), such as vacuolation, formation of syncytia, and fusion of cells, were detected even at fir