Phylogenetic Analysis of the 56-kDa Type-Specific Protein Genes ofOrientia tsutsugamushiin Central Korea

Abstract

There are several antigenic variants of Orientia tsutsugamushi. The 56-kDa type-specific antigen (TSA) is responsible for the antigenic variation. Nucleotide sequences of the 56-kDa TSA obtained from 44 eschar samples of Korean scrub typhus patients and from 40 representative strains retrieved from the GenBank database were analyzed phylogenetically. Clinical patient data were assessed based on the genotyping results. Of the 44 nucleotide sequences, 32 (72.7%) clustered with the Boryong genotype, which is the major genotype in Korea. Eleven nucleotide sequences (25%) clustered with the Kawasaki genotype, not identified in Korea until 2010. One nucleotide sequence was consistent with the Karp genotype. The clinical course of the patients infected with each genotype showed no differences. Diagnostic performance of the immunofluorescence assay (IFA) using the 56-kDa TSA from Gilliam, Karp and Boryong as test antigens were not different for the Boryong and Kawasaki genotypes. Although Boryong is still the predominant genotype, the results suggest that Kawasaki genotype is quite prevalent in Chungbuk province of Korea.

Inappropriateness of Quinolone in Scrub Typhus Treatment Due togyrAMutation inOrientia tsutsugamushiBoryong Strain

“…In Korea, the Boryong strain has been reported throughout the country but predominantly in the southern areas (Chonbuk, Chonnam, Kyoungbuk, and Kyoungnam). In contrast, Karp, Kawasaki and Gilliam strains are more prevalent in the central part of Korea (Kyounggi, Kangwon and Chungcheong) (13, 14). We isolated primarily the Boryong strain from our patients, which is in agreement with previous reports and is in accordance with the location of our institute in the southern part of Korea.…”

Scrub typhus in South India: clinical and laboratory manifestations, genetic variability, and outcome

“…3 Boryong is the predominant strain reported from Korea, while studies from Japan and China have shown a mixture of many strains, which differ between the prefectures. 34,35 Several other studies have reported the prevalence of major genotypes circulating in various endemic geographical locations (Table 4). 12,15,32,[34][35][36][37][38][39] Australia and Taiwan have shown a very high incidence of the TA716 strain, 39,40 and seasonal strain variations have been demonstrated in Chinese and Taiwanese studies.…”

“…34,35 Several other studies have reported the prevalence of major genotypes circulating in various endemic geographical locations (Table 4). 12,15,32,[34][35][36][37][38][39] Australia and Taiwan have shown a very high incidence of the TA716 strain, 39,40 and seasonal strain variations have been demonstrated in Chinese and Taiwanese studies. 12,41 Information on the geographical spread of this disease would be helpful for clinicians suspecting possible scrub typhus in a patient.…”

Genotypic characterization of Orientia tsutsugamushi from patients in two geographical locations in Sri Lanka

“…An increased prevalence of Karp and Karp-like strains has been reported in the Southeast Asian countries, including Malaysia (56%), Thailand (65%), Myanmar (46%), and Philippines (78%) [19–21], Boryong is the predominant strain reported from Korea [22]. However, several studies in India have reported a high prevalence of Kato-like organisms (65%) and the majority have sequence similarity with OT isolates from Korea, Thaiwan, Vietnam and Cambodia [23].…”