• The Journal of the Korean Society for Microbiology
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• v.34 no.5
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• pp.471-478
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• 1999

Spirochetes were isolated from the midgut of Ixodes persulcatus ticks captured at Chungju, Korea and identified as Borrelia afzelii strains by polymerase chain reaction. To determine the pathogenicity of the B. afzelii strains isolated in Korea, the microbiological and pathological features of Lyme disease were observed in C3H/He mice after intraperitoneal inoculation of the fresh isolate of B. afzelii strain. The results are summarized as follows 1) The Borrelia were detected in the tissues of heart, spleen, kidney, urinary bladder and knee joint within 7 days after inoculation of infection by dark field microscopic examination. The isolation rate from heart, urinary bladder and joint was significantly higher than the rate from spleen, kidney, and blood samples. 2) The Borrelia was detected in heart muscle by indirect immunofluorescent antibody test. 3) Antibody to the Borrelia was detected as early as one week after inoculation. 4) The marked tropism of the Borrelia was observed in myocardial, urinary tract and joint tissue. The main pathological features are inflammation in tissues of heart, kidney, joint and urinary bladder. From these results, the Borrelia afzelii strain isolated in Korea were determined as pathogenic strain.

• Korean Journal of Veterinary Research
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• v.39 no.1
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• pp.204-212
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• 1999

The visceral dissemination of Borrelia burgdorferi in New Zealand White rabbits was evaluated following intradermal inoculation of $1{\times}10^8$ spirochetes. We inoculated Borrelia burgdorferi B31, B garinii KW1 and B afzehlii S13, respectively, and monitored the dissemination in the experimentally infected rabbits for 28 days. In the B burgdorferi B31-challenged group, the spirochetes were completely cleared in rabbits at day 1 and visceral dissemination was not demonstrated. However, B garinii KW1 and B afzelii S13 were found to successfully disseminate in visceral organs of rabbits during the experiment period of 28 days. And experimentally infection-derived immunological responses in rabbits were identified with enzyme-linked immunosorbent assay and immunoblot analysis. Based on these results, the differences in the virulence of Lyme borrelial strains were proved in rabbit model.

• Parasites, Hosts and Diseases
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• v.62 no.1
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• pp.151-156
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• 2024

Bovine borreliosis, caused by Borrelia theileri which is transmitted via hard tick bites, is associated with mild clinical symptoms, such as fever, lethargy, hemoglobinuria, anorexia, and anemia. Borrelia theileri infects various animals, such as cattle, deer, horses, goats, sheep, and wild ruminants, in Africa, Australia, and South America. Notably, no case of B. theileri infection has been reported in Korean cattle to date. In this study, 101 blood samples were collected from a Korean indigenous cattle breed, among which 1.98% tested positive for B. theileri via nested PCR. The obtained sequences exhibited high homology with B. theileri strains identified in other regions. Phylogenetic analysis of 16S rRNA confirmed the B. theileri group affiliation; however, flagellin B sequences exhibited divergence, potentially due to regional evolutionary differences. This study provides the first molecular confirmation of B. theileri infection in Korean livestock. Further isolation and nucleotide sequence analyses are necessary to better understand the presence of B. theileri strains in cows in Korea.

• Korean Journal of Veterinary Research
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• v.47 no.3
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• pp.281-283
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• 2007

This study was conducted to survey of Ehrlichia (E.) canis and Borrelia (B.) burgdorferi antibodies among clinically healthy German shepherd dogs (116 females and 120 males) using a ELISA kit (SNAP 3Dx; IDEXX Laboratories, USA) in Korea. Whole blood samples are collected from the 236 dogs and are tested to detect E. canis and B. burgdorferi antibodies by using ELISA kit (SNAP 3Dx; IDEXX Laboratories, USA). Confidence interval comparisions revealed that dogs of 4-6 years have higher prevalence with a seropositive result (CI=0.17-0.45) in E. canis than the other age groups but there are no differences among age groups in B. burgdorferi. Also, no differences with a seropositive result were found among different regions in E. canis and B. burgdorferi antibodies. In conclusion, this study was the first large scale survey of canine E. canis and B. burgdorferi antibodies in Korea and provide an useful reference for clinicians.

• Journal of Life Science
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• v.28 no.5
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• pp.627-637
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• 2018

Motility and chemotaxis are crucial for disease development in many motile pathogens, including spirochetes. In many bacteria, motility is provided by flagella rotation, which is controlled by a chemotaxis-signal-transduction system. Thus, motility and chemotaxis are inextricably linked. Spirochetes are a unique group of bacteria with distinctive flat-wave morphology and corkscrew-like locomotion. This unusual motility pattern is believed to be important for efficient motility within the dense tissues through which these spirochetes preferentially disseminate in a host. Unlike other externally flagellated bacteria-where flagella are in the ambient environment-the flagella of spirochetes are enclosed by the outer membrane and thus are called periplasmic flagella or endoflagella. Although motilityand chemotaxis-associated genes are well studied in some bacteria, the knowledge of how the spirochete achieves complex swimming and the roles of most of the putative spirochetal chemotaxis proteins are still elusive. Recently, cutting-edge imaging methods and unique genetic manipulations in spirochetes have helped to unravel the mystery of motility and chemotaxis in spirochetes. These contemporary advances in understanding the motility and chemotaxis of spirochetes in a host's persistence and disease process are highlighted in this review.

• Biomedical Science Letters
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• v.5 no.2
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• pp.209-212
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• 1999

For the classification of B. burgdorferi sensu lato strains, PCR-restriction fragment length polymorphism (RFLP) analysis was performed. PCR was carried out with B. burgdorferi sensu lato specific primer set (BB uni set), and amplicons of 470-bp DNA were digested with Alu 1. The Alu I restriction polymorphism of the amplicons provided a useful tool for identifying B. burgdorferi sensu late strains. Both amplicons from B. burgdorferi sensu stricto and B. garinii except HPI strain showed identical RFLP pattern (50 bp, 70 bp, and 150 bp), but amplicons from B. afzelii and B. garinii showed two types of subgroups, respectively. The result of PCR-RFLP using extracted DNAs from ticks was similar to those patterns of B. burgdorferi species including B. afzelii.

• Biomedical Science Letters
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• v.4 no.2
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• pp.113-120
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• 1998

To investigate the distribution of Borrelia burgdorferi and human granulocytic ehrlichiosis (HGE) agent in ticks, adult ixodid ticks of Ixodes spp. and Haemaphysalis spp. were collected from the high mountain areas of Kangwon Province. Using DNAs extracted and purified in the collected ticks, polymerase chain reaction (PCR) was performed to amplify the specific nucleotide sequences of both agents. Of the 516 ticks, a total of 68 (13.2%) ticks was positive for Borrelia burgdorferi sensu lato with PCR analysis (2 for B. burgdorferi sensu stricto； 1 for B. afzelii；33 for B. garinii； 8 for B. tanukii；4 for B. turdae). However a little more than half of PCR-positive ticks (37/68) was found to be positive in the southern blot analysis with Bl6S oligonucleotide probe. One hundred and one (19.2%) ticks were positive for Ehrlichia spp. in PCR, and a quarter of them (25/101) was positive in southern blot with El6S oligonucleotide probe. But none of them was found to be the DNA of HGE agent. And 0.6% (3/516) ticks were positive for both of B. burgdorferi sensu late and Ehrlirhia spp. These findings might implicate the possibility of the outbreak of Iyme borreliosis and ehrlichiosis in Korea, and more extensive studies may be need for the diagnosis of multiple tick-borne diseases.

• Journal of Preventive Medicine and Public Health
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• v.51 no.4
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• pp.213-214
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• 2018

Lyme borreliosis (LB) is the most common tick-borne infectious disease in North America, and it was designated as a national notifiable infectious disease in Korea in December 2010. While no cases in Jeju-do were recorded from 2012 to 2016, a recent survey reported that the seroprevalence of Borrelia burgdorferi using enzyme-linked immunosorbent assays in horses in Jeju-do was 19.0% (95% confidence interval, 12.0 to 28.3%). This fact suggests that horses may be a potential reservoir of LB in Jeju-do and that individuals in close contact with horses may be a high-risk group. Thus, a serological study in this high-risk group is urgently needed.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.188.1-188
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• 2002

• Parasites, Hosts and Diseases
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• v.54 no.1
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• pp.97-101
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• 2016

Lyme disease is a tick-borne zoonotic infectious disease caused by Borrelia burgdorferi. The present study assessed the infection status of B. burgdorferi among horses reared in Korea using ELISA and PCR. Between 2009 and 2013, blood samples were collected from 727 horses throughout Korea. Data for each animal including age, gender, breed, and region of sample collection were used for epidemiological analysis. Overall, 38 (5.2%; true prevalence: 5.5%) of 727 horses were seropositive by ELISA. There were statistically significant differences according to breed and region (P<0.001) whose differences might be attributed to the ecology of vector ticks and climate conditions. Using 2 nested PCR, none of the samples tested positive for B. burgdorferi. Thus, a positive ELISA result can indicate only that the tested horse was previously exposed to B. burgdorferi, with no certainty over the time of exposure. Since global warming is likely to increase the abundance of ticks in Korea, continuous monitoring of tick-borne diseases in Korean horses is needed.