• Journal of Medicine and Life Science
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• v.18 no.2
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• pp.25-30
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• 2021

Many people reported suspected food poisoning after consuming food at the same snack bar on June 18, 2020. Thus, an in-depth epidemiological investigation was conducted to identify the infectious agent and establish additional food poisoning prevention measures. The study included people who reported to the local public health center after June 18 with acute gastroenteritis symptoms within 4 days of consuming food from the snack bar. The onset of symptoms and food items consumed by individuals were then investigated via phone calls and on-site visits. Afterward, the infectious agent was identified from human samples (stool or rectal swab) of four restaurant employees and 89 people and from environmental samples (materials, cooking utensils, and water). The analysis revealed that the incubation period ranged from 2 hours to 92 hours, with a median and mode of 16 hours and 12 hours, respectively. Moreover, the epidemic curve had a unimodal shape because of common exposure, which reached its peak on June 18. After monitoring for 8 days, which is more than twice the maximum incubation period of 92 hours, the end of the epidemic was declared on June 28 as no additional cases were reported. Analysis of human and environmental samples revealed Salmonella bareilly of the pulsed-field gel electrophoresis pulsotype SAPX01.017 as the causative agent. Therefore, it was concluded that the food poisoning outbreak was caused by S. bareilly.

• Journal of Ginseng Research
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• v.45 no.1
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• pp.75-85
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• 2021

Background: Invasive infections due to foodborne pathogens, including Salmonella enterica serovar Typhimurium, are prevalent and life-threatening. This study aimed to evaluate the effects of ginsenoside Rg3 (Rg3) on the adhesion, invasion, and intracellular survival of S. Typhimurium. Methods: The impacts of Rg3 on bacterial growth and host cell viability were determined using the time kill and the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assays, respectively. Gentamicin assay and confocal microscopic examination were undertaken to determine the effects of Rg3 on the adhesive and invasive abilities of S. Typhimurium to Caco-2 and RAW 264.7 cells. Quantitative reverse transcription polymerase chain reaction was performed to assess the expression of genes correlated with the adhesion, invasion, and virulence of S. Typhimurium. Results: Subinhibitory concentrations of Rg3 significantly reduced (p < 0.05) the adhesion, invasion, and intracellular survival of S. Typhimurium. Rg3 considerably reduced (p < 0.05) the bacterial motility as well as the release of nitrite from infected macrophages in a concentration-dependent manner. The expression of genes related to the adhesion, invasion, quorum sensing, and virulence of S. Typhimurium including cheY, hilA, OmpD, PrgK, rsgE, SdiA, and SipB was significantly reduced after Rg3 treatment. Besides, the compound downregulated rac-1 and Cdc-42 that are essential for actin remodeling and membrane ruffling, thereby facilitating Salmonella entry into host cells. This report is the first to describe the effects of Rg3 on "trigger" entry mechanism and intracellular survival S. Typhimurium. Conclusion: Rg3 could be considered as a supplement agent to prevent S. Typhimurium infection.

• Journal of Environmental Health Sciences
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• v.48 no.3
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• pp.176-182
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• 2022

Background: The risk of imported infectious diseases has been increasing with the annual rise in the number of international travelers. Objectives: This study aims to analyze the distribution and characteristics of intestinal bacteria isolated in 2019 from residents of Chungcheongnam-do Province with experience of travelling overseas. Methods: Twenty-three former overseas travelers with diarrhea were analyzed to detect viruses and bacteria according to the Manual for Detection of Foodborne Pathogens at Outbreaks. Additionally, antibiotic susceptibility tests and 16s rRNA sequencing were performed. Results: Twenty-five strains of ten pathogens were isolated from 18 samples. Pathogenic E. coli was the most common at 57.7%, followed by Clostridium perfringens (15.4%), Campylobacter spp. (7.7%), and Salmonella spp. (7.7%). The serotype of Salmonella was confirmed as Salmonella Braenderup, II 9,46:g,[m],[s],t:[e,n,x]. Conclusions: It was confirmed that the major enteric bacterial pathogens isolated from overseas travelers in Chungcheongnam-do Province were pathogenic E. coli, as found in other studies. The study on Plesiomonas shigelloides is meaningful in that it is reported as a rare case of infection in Korea. Antibiotic resistance and 16s rRNA analysis were performed, which is expected to provide important basic data for the prevention of traveler's diarrhea.

• Tuberculosis and Respiratory Diseases
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• v.65 no.6
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• pp.537-540
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• 2008

There are few reports of the pleuropulmonary involvement of a non-typhi Salmonella infection in immunocompromised patients with AIDS, malignancy, collagen vascular diseases, extended use of corticosteroids, sickle cell disease, or diabetes. We report a case of a non-immunocompromised patient who presented with concomitant empyema and mediastinitis due to Salmonella without a comorbid disease. A 26-year-old male patient, with a history of pneumonia 5 years earlier and having lived abroad for several years, presented chronic cough and febrile sensation. Pneumonia, empyema and mediastinitis were noted in a chest CT scan and Salmonella enteritidis and ${\beta}-hemolytic$ streptococcus were identified from a culture of the pleural fluid. Initially, he was treated with cefepime, metronidazole and clarithromycin. He was cured clinically and radiographically after an 8 week treatment with antibiotics. In conclusion, this report suggests that S. enteritidis can cause empyema and mediastinitis, albeit rarely.

• Korean Journal of Veterinary Research
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• v.26 no.2
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• pp.229-235
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• 1986

1984년 5월부터 1985년 5월까지 대구(大邱), 경북(慶北), 경남(慶南) 및 충남지역(忠南地域) 7개(個) 양돈장(養豚場)의 자돈(仔豚) 및 성돈(成豚)의 분변(糞便) 및 양돈장(養豚場)의 흙, 하수(下水), 사료(飼料), 추비(推肥), 쥐 등 7,440예(例)와 대구시(大邱市) 도축장(屠畜場)의 도축돈(屠畜豚) 장간막임파절(腸間膜淋巴節) 및 직장내용물(直腸內容物) 555예(例)로부터 분리(分離)한 319주(株)의 Salmonelia속균(屬菌)을 대상으로 항균제(抗菌劑)에 대한 내성(耐性) 및 전달성(傳達性) R plasmid의 분포상황(分布狀況)을 조사(詞査)하였던 바 그 결과(結果)는 다음과 같다. 1. 공시균(供試菌) 319주(株) 중(中) 250주(株)(78.4%)가 ampicillin(An), chloramphenicol(Cm), gentamicin(Gm), kanamycin(Km), nalidixic acid(Na), rifampicin(Rf), streptomycin(Sm), sulfadimethoxine(Su), 또는 tetracycline(Tc)에 내성(耐性)을 나타내었으며, 약제별(藥劑別)로는 Su(74.9%), Sm(53.0%) 및 Tc(28.5%)에 높은 내성(耐性)이 인정(認定)되었다. 2. 내성균(耐性菌) 250주(株)의 전달성(傳達性) R plasmid 보유율(保有率)은 51.2%(128주(株))였으며, 약제별(藥劑別)로는 Am경우 100%, Tc 92. 3% 및 Cm 75.0% 순으로 보유율(保有率)이 높았다. 3. 내성균(耐性菌) 250주(株)의 내성양상(耐性樣相)은 SmSu(91주(株)), Su(59주(株)) 및 TcSmSu(50주(株))내성형(耐性型)이 대부분이었고 R plasmid 전달후(傳達後)의 내성양상(耐性樣相)은 TcSmSu(40주(株)) 및 TcSu(28주(株)) 내성형(耐性型)이 많았다. 4. 양돈장별(養豚場別) 내성균(耐性菌) 출현빈도(出現頻度)는 48.0~93.6%로 다양(多樣)하였고, 전달성(傳達性) R plasmid 보유율(保有率)은 0~77.8%로 내성균(耐性菌) 출현빈도(出現頻度)와 일치(一致)되지 않았다. 5. 공시균(供試菌) 319주(株) 중(中) 각각(各各) 2주(株)는 Rf 및 Gm에 대해 내성(耐性)을 나타내었고, 내성균(耐性菌) 250주(株) 중(中) 73.2%(183주(株))가 다제내성(多劑耐性)이었으므로 Salmonella의 다제내성화(多劑耐性化) 경향(傾向)이 있었다. 6. 내성균(耐性菌) 250주(株) 중(中) R plasmid 전달후(傳達後) 5주(株)는 TcAmCmSmSu내성형(耐性型), 1주(株)는 TcAmKmSmSu내성형(耐性型)임이 확인되었다.

• Journal of Life Science
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• v.16 no.4
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• pp.664-671
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• 2006

We obtained 424 Salmonella enterica serovar Typhi isolates from sporadic cases of infection in Busan during 1996 to 2005. We investigated the trend of antimicrobial resistance and molecular typing by pulsed-field gel electrophoresis (PFGE). Of the total 424 isolates, 6 strains (1.4%) were multidrug-resistant (MDR) S. enterica serovar Typhi isolates, 2 strains (0.5%) were resistant to only nalidixic acid, and the remaining 416 strains (98.1%) were fully susceptible to the 18 antimicrobial agent. PFGE of XbaI-digested chromosomal DNA was performed on 50 sporadic S. enterica serovar Typhi isolates with the objective of investigating the extent of genetic diversity of these isolates in our region. We could find that these isolates were much more heterogeneous and at least 32 different PFGE patterns were generated according by dice coefficient, between 0.69 and 1.0. Restriction fragment patterns consisted of 13 to 18 fragments ranged in size from 20 to 630 kb. The results confirmed that PFGE would be an useful tool for investigating surveillance of sporadic or outbreak case and assessing clonality for S. enterica serovar Typhi in Busan area. Our finding will be valuable in developing rational strategies to control this pathogen and setting the basis of an effective PulseNet system in Korea.

• The Journal of the Korean Society for Microbiology
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• v.21 no.4
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• pp.423-434
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• 1986

The role of macrophages in the resistance of ICR mice to Candida albicans and Salmonella typhimurium was assessed using silica, agent which selectively inactivates macrophages or poly-2-vinylpyridine-N-oxide(PVNO), a lysosomal stabilizing agent. In addition, effect of silica on humoral and cellular immune responses to sheep red blood cells(SRBC) or polyvinylpyroridone(PVP) was examind. Colonyforming units(CFU) of C. albicans or S. typhimurium in the spleen, livers and kidneys of silica-treated or diluent-treated mice were enumerated at various times after infection. Silica was given i. v. to mice at 4 days or 1 day before infection. Although there was no apparent differences in the number of CFU of C. albicans cultured from the spleens or livers of silica-treated and control mice at every assay period, significant differences in the number of CFU of C. albicans in the kidneys of silica-treated and control mice. Namely, silica given to mice 1 day before infection significantly increased the number of CFU of C. albicans in the kidneys at 2, 4 and 6 days after infection, but did not change the number of CFU at 8 days after infection. Silica given to mice at 4 days before infection significantly increased the number CFU in the kidneys at 2 and 4 days after infection, but rather decreased the number of CFU at 8 days after infection. The number of CFU of C. albians cultured from the kidneys of splenectomized which were experimentally infected mice was similar to the number recovered from sham-operated mice at 4 and 8 days postinfection irrespective of time of infection relative to operation. The pretreatment of mice with PVNO appeared to abrogate the silica-induced susceptibility of mice to C. albicans. PVNO alone showed somewhat protective effect against challenge with C. albicans. In contrast, silica treatment did not alter the number of CFU of S. typhimurium recovered from the spleens and kidneys of mice. The administration of silica to mice at 4 days or 1 day before SRBC immunization significantly suppressed delayed-type hypersensitivity(DTH) reactions to SRBC and antibody production to SRBC, a thymus-dependent antigen and PVP, a thymus-independent antigen. These results provide evidence that macrophages play an important role in susceptibility to Candida infection and strongly demonstrated that macrophages play an essential role in the induction of immune responses in mice.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1233-1237
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• 2005

Catechin products in green tea extract was prepared to investigate antibacterial activity on the pathogenic bacteria. Survival of pathogenic bacteria (MASA - methicillin resistant Staphylocouus aureus, E.coli O157 and S. typhimurium Sal-13) in tryptic soy agar(TSA) containing Catechin products powder incubated at various concentration was evaluated. TSA containing $0{\sim}2%(w/v)$ of Catechin products was inoculated approximately $10^4\;CFU/ml$ of pathogenic bacteria and incubated at $37^{\circ}C$ for 24 hours. The plate counting technique and clear zoon test were used to test survival effect of the Catechin products. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was derived from the survival curves of pathogenic bacteria. S. typhimurium Sal-13 was the most sensitive strain to Catechin products. This result suggested that Catechin products can be used as an effective natural antibacterial agent.

• Pediatric Infection and Vaccine
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• v.13 no.2
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• pp.147-155
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• 2006

Purpose : The purpose of this study is to evaluate epidemiological data of pathogens obtained from stool exams and compare them with the clinical course in pediatric patients with symptoms of acute gastroenteritis. Methods : Subjects were selected from patients presenting with symptoms of acute gastroenteritis who visited the outpatient clinic or who were admitted to the Dankook University Hospital from December of 2004 to December of 2005. Stool exams for 17 pathogens was performed. RT-PCR was used to detect norovirus and enzyme-linked immunoabsorbant assay (ELISA) was used to detect rotavirus, adenovirus and astrovirus in the subjects stool samples. Ten different species of bacteria(Salmonella spp., Shigella spp., Clostridium perfrigens, Campylobacter spp., Escherichia coli, Vibrio spp., Staphylococcus aureus, Bacillus cereus, Yersinia spp., and L. monocytogenes) were each selectively cultivated and enzyme immunoassays(EIA) was used to test for antigens for C. parvum, E. histolytica and G. lamblia. Retrospective chart review was performed for comparisons of clinical manifestations. Results : A total of 215 subjects was selected and of these 89 cases(41.4%) showed positive results for at least one pathogen. Male to female ratio was 1.3:1. Age distribution showed 4 cases less than one month(4.5%), 4 cases from 1~2 months(4.5%), 24 cases from 3~12 months(26.7%), 47 cases form 13~48 months(52.8%), 10 cases greater than 48 months (21.2%). Viruses showed the greatest proportion of cases with 68 subjects(77.5%), of these rotavirus being the most commonly reported in 50 cases. Bacteria was identified in 26 cases (29.2%), of these nontyphoidal salmonella was noted in 10 cases. Protozoa followed with 21 cases(23.6%), of these C. parvum was noted in 11 cases and G. lamblia was noted in 10 cases. Mixed infections with more than two pathogens were seen in 22 cases(24.7%), of these viral infection with accompanying parasitic infection was seen in 12(54.5%) cases. Conclusion : In this study we examined various pathogens known to cause acute gastroenteritis in children. Further studies for various pathogens can provide useful information for management of the acute gastroenteritis.

• Journal of Preventive Medicine and Public Health
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• v.38 no.2
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• pp.117-124
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• 2005

Before twentieth centuries and during early twentieth centuries, communicable diseases were the major cause of morbidity and mortality in Korea. But reliable data are not available. After 1975, the overall morbidity and mortality from communicable diseases, rapidly declined. Recently many new pathogenic microbes were recognized: L. monocytogenes, Hantaan virus, Y. pseudotuberculosis, P. multocida, L. pneumophilia, Human immunodeficiency virus (HIV), G. seoi, H. capsulatum, C. burnetii, V. cholerae O139, C. parvum, F. tularensis, E. coli O157:H7, B. burgdorferi, S. Typhimurium DT104, Rotavirus, hepatitis C virus and so on. Since the first HIV infection recognized in 1985, the reported cases of infection and deaths from HIV/AIDS have been steady increased each year. Legionnaire's disease, E. coli O157:H7 colitis, listeriosis and crytosporidiasis have been occurring just sporadically among immunocompromized cases. Many re-emerging communicable diseases were occurred in Korea: leptospirosis, malaria, endemic typhus, cholera, tsutsugamushi disease, salmonellosis, hepatitis A, shigellosis, mumps, measles, acute hemorrhagic conjunctivitis, brucellosis and so on. Leptospirosis and tsutsugamushi diseases have been noticed as major public health problems since 1980s. The malaria that had been virtually disappeared for a decade has reappeared from 1993 with striking increase of patients in recent 3-4 years. The distributions of salmonella and shigella serotypes have been changed a lot in recent few decades. Furthermore rapid emergence of antibiotic-resistant bacterial strains induces more difficult and complex problems in control of communicable diseases. We must recognize on the importance of environment and ecosystem conservation and careful prescription of anti-microbial agent in order to prevent communicable diseases.