• Parasites, Hosts and Diseases
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• v.46 no.3
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• pp.199-201
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• 2008

Toxoplasma gondii is an obligate intracellular zoonotic protozoan with a worldwide distribution. It infects humans as well as a broad spectrum of vertebrate hosts. Cats and wild felidae play crucial roles in the epidemiology of toxoplasmosis. This study was performed to survey the prevalence of T. gondii infection among stray cats in the Gyeonggi-do, Republic of Korea. A total of 174 stray cat blood samples were collected from Gwacheon-si (n = 20), Bucheon-si (82), and Yangju-si (72). Positive sera for T. gondii were identified in 14 samples (8.1%) exclusively via the latex agglutination test, 28 (16.1%) via ELISA, and 23 (13.2%) via PCR analysis. The overall infection rate of female stray cats (29.2%) presented as higher than that of male cats (24.0%). This study suggests that T. gondii is widespread in the stray cat population of Gyeonggi-do, Korea. It is urgently needed to control urban stray cat population and to reduce the risk of zoonotic transmission of toxoplasmosis to other animal hosts and humans.

• IMMUNE NETWORK
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• v.23 no.6
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• pp.47.1-47.16
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• 2023

Scrub typhus, a mite-borne infectious disease, is caused by Orientia tsutsugamushi. Despite many attempts to develop a protective strategy, an effective preventive vaccine has not been developed. The identification of appropriate Ags that cover diverse antigenic strains and provide long-lasting immunity is a fundamental challenge in the development of a scrub typhus vaccine. We investigated whether this limitation could be overcome by harnessing the nanoparticle-forming polysorbitol transporter (PST) for an O. tsutsugamushi vaccine strategy. Two target proteins, 56-kDa type-specific Ag (TSA56) and surface cell Ag A (ScaA) were used as vaccine candidates. PST formed stable nano-size complexes with TSA56 (TSA56-PST) and ScaA (ScaA-PST); neither exhibited cytotoxicity. The formation of Ag-specific IgG2a, IgG2b, and IgA in mice was enhanced by intranasal vaccination with TSA56-PST or ScaA-PST. The vaccines containing PST induced Ag-specific proliferation of CD8⁺ and CD4⁺ T cells. Furthermore, the vaccines containing PST improved the mouse survival against O. tsutsugamushi infection. Collectively, the present study indicated that PST could enhance both Ag-specific humoral immunity and T cell response, which are essential to effectively confer protective immunity against O. tsutsugamushi infection. These findings suggest that PST has potential for use in an intranasal vaccination strategy.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.3
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• pp.429-438
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• 2011

Mastitis is characterized by physical, chemical and bacteriological changes in the milk and pathological changes in the glandular tissue of the udder and affects the quality and quantity of milk. The bacterial contamination of milk from the affected cows render it unfit for human consumption and provides a mechanism of spread of diseases like tuberculosis, sore-throat, Q-fever, brucellosis, leptospirosis etc. and has zoonotic importance. Somatic cell count (SCC) is a useful predictor of intramammary infection (IMI) that includes leucocytes (75%) i.e. neutrophils, macrophages, lymphocytes, erythrocytes and epithelial cells (25%). Leucocytes increase in response to bacterial infection, tissue injury and stress. Somatic cells are protective for the animal body and fight infectious organisms. An elevated SCC in milk has a negative influence on the quality of raw milk. Subclinical mastitis is always related to low milk production, changes to milk consistency (density), reduced possibility of adequate milk processing, low protein and high risk for milk hygiene since it may even contain pathogenic organisms. This review collects and collates relevant publications on the subject.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.313-324
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• 2020

Coronavirus disease 2019 (COVID-19), which causes serious respiratory illness such as pneumonia and lung failure, was first reported in Wuhan, the capital of Hubei, China. The etiological agent of COVID-19 has been confirmed as a novel coronavirus, now known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is most likely originated from zoonotic coronaviruses, like SARS-CoV, which emerged in 2002. Within a few months of the first report, SARS-CoV-2 had spread across China and worldwide, reaching a pandemic level. As COVID-19 has triggered enormous human casualties and serious economic loss posing global threat, an understanding of the ongoing situation and the development of strategies to contain the virus's spread are urgently needed. Currently, various diagnostic kits to test for COVID-19 are available and several repurposing therapeutics for COVID-19 have shown to be clinically effective. In addition, global institutions and companies have begun to develop vaccines for the prevention of COVID-19. Here, we review the current status of epidemiology, diagnosis, treatment, and vaccine development for COVID-19.

• Korean Journal of Veterinary Research
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• v.44 no.2
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• pp.269-277
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• 2004

Trichinella spiralis is one of the important zoonotic parasites with a wide variety of vertebrates hosts in nature. The purpose of this study were to analyze ESP(Excretory-Secretory Protein) antigen, to evaluate ELISA for the serological diagnosis of Trichinosis, and to survey T. spiralis infection in finishing pigs using the pepsin digestion method and ELISA in Korea. In the analysis of ESP antigen by SDS-PAGE and Western blot, 4 major bands (70, 55, 52.6, and 49 kDa) were revealed from the ESP antigen. Predilection sites of T. spiralis were the diaphragm, the tongue, masseter muscles, intercostal muscle, and hindlimb in orders in the experimentally infected rats. Sera from 581 swine were tested by ELISA with ESP antigen. The 54 (9.3%) sera were suspected as positive reactors, however, these 54 sera were determined as false positives by the use of Western blotting. This study demonstrated that the ELISA was not suitable for the examination of T. spiralis in pork. The diaphragm muscle samples of 251 finishing pigs were tested by the method of pepsin-digestion for the presence of Trichinella larvae, however, T. spiralis was not detected from the samples. We could not find out T. spiralis infection in pig in Korea pork.

• Microbiology and Biotechnology Letters
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• v.50 no.4
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• pp.457-464
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• 2022

A public health concern emerging from a zoonotic disease. Monkeypox is caused by the orthopoxvirus specie Monkeypox virus (MPXV). Monkeypox was identified as the most common orthopoxvirus infection in humans following the eradication of smallpox. Monkeypox has a similar clinical presentation to smallpox. The MPXV is now considered a high-threat pathogen that causes a serious public-health problem. The continuous spread of Monkeypox virus from West Africa to all other places around the world throughout 2018 to 2022, have raised concerns that MPXV could have emerged to acquire the immunological and ecological niche vacated by smallpox virus. This review highlights the current knowledge about Monkeypox evolution, infection biology, and epidemiology around the world since from 1970 to 2022, with a focus on the human, viral, and cellular factors that influence virus emergence, infection, spread, and maintenance in nature. This paper also discusses the current therapeutic options for Monkeypox treatment and control. Under the right conditions, with limited smallpox vaccination and very little orthopoxvirus immunity in some areas of the world, MPXV could become a more efficient human pathogen. Finally, the review identified knowledge gaps, particularly in terms of identifying a definitive reservoir host for monkeypox and proposes future research endeavors to address the unanswered questions.

• Korean Journal of Veterinary Research
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• v.46 no.3
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• pp.255-261
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• 2006

Experimental animals have been used to biological and medical purposes and the animals must be, for these purposes, healthy and clean to microbial infection. However, the animals can be easily exposed to pathogenic microorganism via several routes. Of the routes, environmental conditions are the most important factors to keep the animals healthy and clean, especially air condition. Monitoring of air-condition has been required to keep the animal healthy and clean. However, any guideline is not available for experimental conditions with pigs. Therefore, the sampling times and points were compared in different conditions to establish an optimal protocol for monitoring of air borne bacteria. Tryptic soy agar(TSA), blood agar containing 5% defibrinated sheep blood and Sabraud dextrose agar(SDA) were used as media to capture total bacteria, pathogenic bacteria and fungi, respectively. Two methods, compulsive capture using an air-sampler and capturing fall-down bacteria were used to capture the microorganisms in the air. The points and time of capturing were different at each experiment. Air borne microorganisms were captured at three and five points in the open and closed equipments, respectively. Air was collected using an air-sampler for 1 min and 5 min and the agar plates as open status were left from 30 min to 2hr. At first, we monitored an experimental laboratory which dealt with several pathogenic bacteria and then, a protocol obtained from the investigation was applied to open or close experimental conditions with pigs. Number of bacteria was high from 10:00 to 15:00, especially on 13:30-15:30 but sharply decreased after 17:00. The tendency of the number of bacteria was similar between two methods even though the absolute number was higher with air sampler. Critical difference in the number of cells was observed at 5 min with air sampler and 2 hr with fall-down capturing method. However, 1 min with air sampler and 1 hr with fall-down capturing were the best condition to identify bacterial species collected from the air. Number of bacteria were different depending on the sampling points in closed condition but not in opened condition. Based on our results, a guide-line was suggested for screening air-borne microorganism in the experimental conditions with pigs.

• Journal of Veterinary Science
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• v.24 no.3
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• pp.38.1-38.12
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• 2023

Background: Poor disease management and irregular vector control could predispose sheltered animals to disease such as feline Bartonella infection, a vector-borne zoonotic disease primarily caused by Bartonella henselae. Objectives: This study investigated the status of Bartonella infection in cats from eight (n = 8) shelters by molecular and serological approaches, profiling the CD4:CD8 ratio and the risk factors associated with Bartonella infection in shelter cats. Methods: Bartonella deoxyribonucleic acid (DNA) was detected through polymerase chain reaction (PCR) targeting 16S-23S rRNA internal transcribed spacer gene, followed by DNA sequencing. Bartonella IgM and IgG antibody titre, CD4 and CD8 profiles were detected using indirect immunofluorescence assay and flow cytometric analysis, respectively. Results: B. henselae was detected through PCR and sequencing in 1.0% (1/101) oral swab and 2.0% (1/50) cat fleas, while another 3/50 cat fleas carried B. clarridgeiae. Only 18/101 cats were seronegative against B. henselae, whereas 30.7% (31/101) cats were positive for both IgM and IgG, 8% (18/101) cats had IgM, and 33.7% (34/101) cats had IgG antibody only. None of the eight shelters sampled had Bartonella antibody-free cats. Although abnormal CD4:CD8 ratio was observed in 48/83 seropositive cats, flea infestation was the only significant risk factor observed in this study. Conclusions: The present study provides the first comparison on the Bartonella spp. antigen, antibody status and CD4:CD8 ratio among shelter cats. The high B. henselae seropositivity among shelter cats presumably due to significant flea infestation triggers an alarm of whether the infection could go undetectable and its potential transmission to humans.

• Journal of Veterinary Clinics
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• v.7 no.2
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• pp.521-525
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• 1990

The present investigation confirms the zoonotic significance of Microspoum canis infection in five patients who had direct contact with diseased dogs and cats. Typical ringworm type lesions were mainly encountered on the exposed areas of the body. M. canis was isolated from the cutaneous lesions of man ana infected pets ; and also directly demonstrated in skin materials. However, the fungus could neither be recovered from the non-contact group nor from the saprobic environment. The isolates from man, dog, and cat showed similar gross as well as microscopic morphology. Further genetic studies so indicated that all the human and animal isolates of M. canis were(-) mating type. It is believed that transmission of zoophilic dermatophytes from animal to man occurs more commonly with direct exposure. In addition, the epidemiology and preventive measures are also discussed.

• Parasites, Hosts and Diseases
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• v.47 no.4
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• pp.413-415
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• 2009

Genotyping of Toxoplasma gondii has been performed in 23 PCR positive blood samples from stray cats in Korea. We used 2 separate PCR-restriction fragment length polymorphism (RFLP) patterns of SAG2 gene, amplifying the 5' and 3' ends of the locus. The results revealed that all samples belonged to the type I clonal lineage. Although T. gondii organisms were not isolated from the samples, the results of the present study represent that stray cats with T. gondii infection should be seriously concerned in our environment. Adequate and continuous control programs of stray cats are needed to reduce the risk of transmission of T. gondii as a zoonotic infection threatening the public health.