Severe Fever with Thrombocytopenia Syndrome Virus Infection or Mixed Infection with Scrub Typhus in South Korea in 2000–2003

Abstract

Severe fever with thrombocytopenia syndrome is a tick-borne viral disease, with a high mortality rate that was first reported in China in 2009. Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi, a bacterium transmitted to humans through chigger mite bites. Severe fever with thrombocytopenia syndrome and scrub typhus are endemic to South Korea. To investigate evidence of severe fever with thrombocytopenia syndrome virus (SFTSV) infection or mixed infection with scrub typhus in South Korea, we examined 2,329 sera samples collected from patients presenting from November 1, 2000, to November 1, 2003, for the diagnosis of rickettisal diseases at Seoul National University, Seoul, South Korea. We found retrospective evidence of SFTSV infection or mixed infection with scrub typhus in South Korea in 2000-2003. Severe fever with thrombocytopenia syndrome virus infections in South Korea occurred before previously reported cases and were more concurrent with those in China. It is important to consider SFTSV infection in patients with scrub typhus.

Genotypic Heterogeneity of Orientia tsutsugamushi in Scrub Typhus Patients and Thrombocytopenia Syndrome Co-infection, Myanmar

“…SFTSV infections are endemic in eastern Asia, and retrospective studies have confirmed its presence in China in 1996 (6), South Korea in 2000 7, Japan in 2005 (8), and Vietnam in 2017 (9). In addition, mixed infection with SFTSV and O. tsutsugamushi has been detected in patients in South Korea, where both pathogens are endemic (7,10). These results further emphasize the urgent need for epidemiologic studies of vectorborne diseases in areas of endemicity to improve our ability to accurately differentiate febrile infectious diseases with atypical signs and symptoms during the initial stages so they can be promptly treated.…”

“…We compared results of phylogenetic analysis of the 9 tsa56 gene sequences with sequences from 17 protogenotypes (1), which revealed >5 genotypes, including Karp_A (4/9, 44.4%), Karp_B (1/9, 11.1%), Kato_B (2/9, 22.2%), Gilliam (1/9, 11.1%), and JG_C (1/9, 11.1%) ( Figure 2). Finally, we used reverse transcription PCR analysis to investigate possible SFTSV infection in the patients (7,9,13). Among 152 patients' serum samples, 5 (3.3%) were positive for the partial small (S) segment of the SFTSV RNA genome, indicating SFTSV infection.…”

Developing a multiplex loop-mediated isothermal amplification assay (LAMP) to determine severe fever with thrombocytopenia syndrome (SFTS) and scrub typhus

“…In addition, these two diseases share common clinical features, such as fever, nausea, vomiting, diarrhea, headache, and muscle pain, as well as overlapping disease regions. Furthermore, many cases of coinfection with SFTSV and O. tsutsugamushi have been reported [43][44][45].…”

SFTSV infection in rodents and their ectoparasitic chiggers

“…In recent years, with more and more reports of co-infection of SFTSV and O . tsutsugamushi [ 12 , 29 – 31 ], as well as, SFTS and scrub typhus had overlapped epidemic seasons [ 30 , 32 , 33 ], it is suspected that chiggers might play a role in the transmission of SFTSV. In addition, a Chinese literature reported that SFTSV was detected by PCR in mites ( Laelaps echidninus , family Laelapidae and L .…”

“…In recent years, with more and more reports of co-infection of SFTSV and O. tsutsugamushi [12,[29][30][31], as well as, SFTS and scrub typhus had overlapped epidemic seasons [30,32,33], it is suspected that chiggers might play a role in the transmission of SFTSV. In addition, a Chinese literature reported that SFTSV was detected by PCR in mites (Laelaps echidninus, family Laelapidae and L. scutellare, family Trombiculidae) collected from rodents and goats in Jiangsu Province [34], which further deepened the suspicion of chigger's role in transmission of SFTSV.…”