1.Molecular Detection and Phylogenetic Analysis of Anaplasma phagocytophilum in Horses in Korea
Min Goo SEO ; In Ohk OUH ; Eunsang CHOI ; Oh Deog KWON ; Dongmi KWAK
The Korean Journal of Parasitology 2018;56(6):559-565
The identification and characterization of pathogenic and zoonotic tick-borne diseases like granulocytic anaplasmosis are essential for developing effective control programs. The differential diagnosis of pathogenic Anaplasma phagocytophilum and non-pathogenic A. phagocytophilum-like Anaplasma spp. is important for implementing effective treatment from control programs. The objective of the present study was to investigate the prevalence of Anaplasma spp. in horses in Korea by nucleotide sequencing and restriction enzyme fragment length polymorphism assay. Of the 627 horses included in the study, only 1 (0.2%) was infected with A. phagocytophilum. Co-infection with A. phagocytophilumlike Anaplasma spp. was not detected in the study. The 16S rRNA sequence of A. phagocytophilum was similar (99.5–100%) to A. phagocytophilum 16S rRNA isolated from horses in other countries. PCR adapted to amplify A. phagocytophilum groEL and msp2 genes failed to generate amplicons, suggesting genetic diversity in these genes. This study is the first molecular detection of A. phagocytophilum in horses in Korea. Human granulocytic anaplasmosis and animal infection of A. phagocytophilum have been reported in Korea recently. Because of vector tick distribution, global warming, and the increase of the horse industry, horses should be considered as a potential reservoir for A. phagocytophilum, and cross infectivity should be evaluated even though a low prevalence of infection was detected in this study. Furthermore, continuous surveillance and effective control measures for A. phagocytophilum should be established to prevent disease distribution and possible transmission to humans.
Anaplasma phagocytophilum
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Anaplasma
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Anaplasmosis
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Animals
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Coinfection
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Diagnosis, Differential
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Genetic Variation
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Global Warming
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Granulocytes
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Horses
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Humans
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Korea
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Phylogeny
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Polymerase Chain Reaction
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Polymorphism, Restriction Fragment Length
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Prevalence
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Tick-Borne Diseases
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Ticks
2.Nasopharyngeal Pneumococcal Carriage of Children Attending Day Care Centers in Korea: Comparison between Children Immunized with 7-valent Pneumococcal Conjugate Vaccine and Non-immunized.
Kyung Hyo KIM ; Jung Yun HONG ; Hyunju LEE ; Ga Young KWAK ; Chan Hee NAM ; Soo Young LEE ; Eunsang OH ; Jigui YU ; Moon H NAHM ; Jin Han KANG
Journal of Korean Medical Science 2011;26(2):184-190
To confirm the effect of 7-valent pneumococcal conjugate vaccine (PCV7), pneumococcal nasopharyngeal (NP) carriage was compared between vaccinated (3 + 1 doses PCV7) and non-vaccinated children. Vaccinated subjects were recruited from highly vaccinated regions (> or = 60%), Seoul and Incheon whereas control subjects were recruited from Jeju Island where vaccination rates are low (< 15%). NP swabs were obtained from 400 children aged 18-59 months. Serotype and antibiotic susceptibility was analyzed. Pneumococcal carriage rate was 18.0% (36/200) and 31.5% (63/200) for the vaccinated and control group, respectively. Among those vaccinated, 41.7% (15/36) of the serotypes were vaccine-related type (VRT: 6A, 6C, 19A) with the most common serotype 6C. The next common type was non-typable/non-capsule 30.6% (11/36) followed by non-vaccine type 16.7% (6/36) and vaccine type (VT) serotypes were found in only 11.1% (4/36). In contrast, 52.4% (33/63) of the isolates in the control group were VT. Resistance rates for penicillin and erythromycin were lower in the vaccine group (vaccine vs control; penicillin 45.2% vs 71.4%, erythromycin 74.2% vs 90.5%, P < 0.05). Multi-drug resistance was also lower in vaccinated subjects (vaccine vs control; 45.2% vs 69.8%, P < 0.05). PCV7 reduces carriage in VT which leads to replacement of pneumococci by antibiotic susceptible VRT or non-vaccine type strains.
Adult
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Carrier State/*immunology/prevention & control
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Child
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*Child Day Care Centers
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Child, Preschool
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Humans
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*Immunization
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Infant
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Male
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Microbial Sensitivity Tests
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Nasopharynx
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Pneumococcal Infections/*epidemiology/immunology/*prevention & control
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Pneumococcal Vaccines/*administration & dosage
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Prospective Studies
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Republic of Korea/epidemiology
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Serotyping
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Streptococcus pneumoniae/*isolation & purification
3.Serological Detection of Borrelia burgdorferi among Horses in Korea.
Seung Hun LEE ; Sun Hee YUN ; Eunsang CHOI ; Yong Soo PARK ; Sang Eun LEE ; Gil Jae CHO ; Oh Deog KWON ; Dongmi KWAK
The Korean Journal of Parasitology 2016;54(1):97-101
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.
Animals
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Antibodies, Bacterial/blood
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Borrelia burgdorferi/*physiology
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Enzyme-Linked Immunosorbent Assay/veterinary
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Female
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Horse Diseases/*epidemiology
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Horses
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Lyme Disease/epidemiology/*veterinary
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Male
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Republic of Korea/epidemiology