• Korean Journal of Veterinary Service
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• v.34 no.4
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• pp.353-359
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• 2011

Fowl cholera is a contagious acute and chronic disease caused by Pasteurella multocida in both domesticated and wild birds. Acute fowl cholera in both chickens and wild birds has recently been documented in Korea, but the chronic form has not been reported in Korea until now. This study describes the first outbreak of chronic fowl cholera in 13-week-old Arbor Acre broiler breeder chickens submitted to the College of Veterinary Medicine, Kyungpook National University in April 2006. The clinical signs of the affected flock of 9,621 chickens were lameness caused by swollen hock joints, diarrhea, ruffled feathers, and an average weekly mortality of 1.0%. At necropsy, purulent or caseous exudates were found in the hock and wing joints, humerus, and eyes, and severe pneumonia and pericarditis were discovered. Eleven bacterial isolates obtained from the liver, joint, infraorbital sinus and sternal bursa of the submitted chickens were all identified as Pasteurella multocida based on their physiological and biochemical characteristics. Five isolates were examined for antimicrobial susceptibility against 21 different antimicrobial agents including ampicillin. All were resistant to kanamycin, neomycin, and streptomycin, and some were resistant to gentamicin. The tested isolates were all susceptible to the other 17 antimicrobial agents. All 11 isolates were capsular serogroup A based on multiplex polymerase chain reaction. In addition, two of five isolates used in the antimicrobial susceptibility test were identified as somatic serotype 1 by an agar gel diffusion precipitin test, while the others were non-typable.

• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.334-341
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• 2003

This study was carried out to investigate the cause of cholera outbreak in Gyeongbuk province in 2001.90 strains of Vibrio cholerae O1 El Tor serotype Inaba were isolated from diarrheal patients. By multiplex-PCR, all of the isolated strains revealed positive for detection ctxA, hlyA and tcpA genes. There were DNA sequence difference of the cholera-toxin subunit A gene and subunit B gene between isolated V. cholerae O1 and the strain of GenBank. In analysis of PFGE patterns, all of the isolated strains were showed the same DNA fragments. We also collected plankton samples in the east coast of Gyeongbuk to isolate V. cholerae O1 and V. cholerae O139 from August to October 2002. The samples were examined to detect the rfb gene and cholera-toxin gene by multiplex-PCR. The cholera-toxin gene was detected and then we tried to isolate V. cholerae O1 and V. cholerae O139, but they were not isolated.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.736-744
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• 2023

The introduction of the toxT-139F allele triggers the expression of TCP (toxin co-regulated pilus) and CT (cholera toxin) under simple laboratory culture conditions in most Vibrio cholerae strains. Such V. cholerae strains, especially strains that have been used in OCVs (oral cholera vaccines), can induce antibody responses against TCP in animal models. However, CT produced in these V. cholerae strains is secreted into the culture medium. In this study, V. cholerae strains that can express intracellular CTB under the control of the toxT-139F allele have been constructed for potential application in OCVs. First, we constructed a recombinant plasmid directly linking the ctxAB promoter to ctxB without ctxA and confirmed CTB expression from the plasmid in V. cholerae containing the toxT-139F allele. We constructed another recombinant plasmid to express NtrCTB, from which 14 internal amino acids-from the 7^th to the 20^th amino acid-of the leader peptide of CTB have been omitted, and we found that NtrCTB remained in the cells. Based on those results, we constructed V. cholerae strains in which chromosomal ctxAB is replaced by ntrctxB or ntrctxB-dimer. Both NtrCTB and NtrCTB-dimer remained in the bacterial cells, and 60% of the NtrCTB-dimer in the bacterial cells was maintained in a soluble form. To develop improved OCVs, these strains could be tested to see whether they induce immune responses against CTB in animal models.

• Bulletin of the Korean Mathematical Society
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• v.54 no.6
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• pp.1893-1912
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• 2017

In this paper, we aim to construct a nonstandard finite difference (NSFD) scheme to solve numerically a mathematical model for cholera epidemic dynamics. We first show that if the basic reproduction number is less than unity, the disease-free equilibrium (DFE) is locally asymptotically stable. Moreover, we mainly establish the global stability analysis of the DFE and endemic equilibrium by using suitable Lyapunov functionals regardless of the time step size. Finally, numerical simulations with different time step sizes and initial conditions are carried out and comparisons are made with other well-known methods to illustrate the main theoretical results.

• Korean Journal of Veterinary Research
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• v.6 no.1
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• pp.31-36
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• 1966

The free amino acid contents in several tissues of swine were analyzed qualitatively by means of two dimentional paper chromatography. The tissues used were liver, kidney and spleen that were obtained from normal, immunized and hog cholera infected swines. The results obtained are as follows: 1. Liver: 20 amino acids were detected in normal, 17 in immunized and 15 in infected swines. 2. Kidney: 16 amino acids were detected in normal, 13 in immunized and infected swines. 3. Spleen: 15 amino acids were detected in normal in immunized and 13 in infected swines. 4. Glutamic acid, leucine, serine and threonine were present in high concentration in all of the cases examined. 5. The free amino acids were appeard to be decreased in the infected tissues with hog cholera virus.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.2
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• pp.103-108
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• 2001

Hog cholera virus(HCV) was purified from virus infected Bovine kidney cells. From this virus, total protein was analyzed by SDS-PAGE gel electrophoresis and about 55 kDa band of E2 envelope protein was detected. The viral RNA was purified and E2 cDNA was amplified by RT-PCR. E2 cDNA fragment was cloned to PCRII-TOPO cloning vector and named pE2. The analysis of nucleotide sequence showed that this E2 cDNA fragment inserted into pE2 was 1191 nucleotides long and coded 397 amino acids.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.215-221
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• 1990

The present study was intended to use the peroxidase-antiperoxidase method for the identification of hog cholera virus(HCV) in the lymphatic organs of HCV-infected pigs. Sections were incubated with primary antibody (rabbit anti-HCV polyclonal or mouse anti-HCV monoclonal), followed by incubation with linkserum (goat anti-rabbit IgG) in excess and rabbit or mouse PAP complex. The viral antigen was localized mainly in the cytoplasms of lymphoid cells and macrophages. Positive reaction cells were frequently detected in the marginal areas of the germinal centers of the spleens, and also found in the tensils and lymph nodes. The method approved to be highly specific for the identification of the virus and allowed a precise localization of the viral antigen in infected cells.

• KOREAN POULTRY JOURNAL
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• v.5 no.10 s.48
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• pp.97-97
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• 1973

• KOREAN POULTRY JOURNAL
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• v.16 s.172
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• pp.106-110
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• 1984

• Journal of Preventive Medicine and Public Health
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• v.35 no.4
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• pp.295-304
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• 2002

Objectives : This study was carried out to investigate the cause, magnitude and transmission route of the cholera outbreak in 2001 Methods : The study population were those persons who ingested foods at the restaurant, were confirmed as cholera patients, had symptoms of diarrhea and sewed as workers at the restaurant. A questionnaire survey and microbiological examinations on the microbes isolated from rectal swabs were conducted. Of the cases, 316 food histories were surveyed by an analysis of the restaurant menu. Results : There were 139 confirmed cases of cholera reported in Korea in 2001. Of these, 104 were related to the restaurant. By region, Gyeongsangbuk-do had the highest incidence with 91 cases. Of these 91 cases, 74 had ingested foods at the restaurant, 2 were employees and 3 were secondary infection cases within the families. The results of the odds ratio analysis of the 316 persons having ingested foods at the restaurant were as follows: sandwiches 5.07 (95% CI, 1.85-14.59), soybean curd 2.45 (95% CI, 1.09-5.56), noodles 2.34 (95% CI, 1.24-4.42), steamed squid 2.01 (95% CI, 1.17-3.47) and vinegared rice 1.82 (95%, CI, 1.08-3.09). It was certain the restaurant in question was the cause of the 2001 outbreak. Conclusions : We suspected that more than one restaurant employee contaminated foods served at the restaurant. In addition, eating raw fishes purchased at the Pohang Fisheries infected the employees of the restaurant. There is a possibility that these raw fishes were themselves contaminated by cholera bacilli in the sea.