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Valusenko-Mehrkens R, Schilling-Loeffler K, Johne R, Falkenhagen A. VP4 Mutation Boosts Replication of Recombinant Human/Simian Rotavirus in Cell Culture. Viruses 2024; 16:565. [PMID: 38675907 PMCID: PMC11054354 DOI: 10.3390/v16040565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 03/22/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
Rotavirus A (RVA) is the leading cause of diarrhea requiring hospitalization in children and causes over 100,000 annual deaths in Sub-Saharan Africa. In order to generate next-generation vaccines against African RVA genotypes, a reverse genetics system based on a simian rotavirus strain was utilized here to exchange the antigenic capsid proteins VP4, VP7 and VP6 with those of African human rotavirus field strains. One VP4/VP7/VP6 (genotypes G9-P[6]-I2) triple-reassortant was successfully rescued, but it replicated poorly in the first cell culture passages. However, the viral titer was enhanced upon further passaging. Whole genome sequencing of the passaged virus revealed a single point mutation (A797G), resulting in an amino acid exchange (E263G) in VP4. After introducing this mutation into the VP4-encoding plasmid, a VP4 mono-reassortant as well as the VP4/VP7/VP6 triple-reassortant replicated to high titers already in the first cell culture passage. However, the introduction of the same mutation into the VP4 of other human RVA strains did not improve the rescue of those reassortants, indicating strain specificity. The results show that specific point mutations in VP4 can substantially improve the rescue and replication of recombinant RVA reassortants in cell culture, which may be useful for the development of novel vaccine strains.
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Affiliation(s)
| | | | | | - Alexander Falkenhagen
- Department of Biological Safety, German Federal Institute for Risk Assessment, 10589 Berlin, Germany; (R.V.-M.); (K.S.-L.); (R.J.)
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Kim JS, Jeong HW, Park SH, Kim JA, Jin YH, Kim HS, Jung S, Lee JI, Lee JH. Genotypic shift in rotavirus associated with neonatal outbreaks in Seoul, Korea. J Clin Virol 2023; 164:105497. [PMID: 37253299 DOI: 10.1016/j.jcv.2023.105497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 05/22/2023] [Accepted: 05/24/2023] [Indexed: 06/01/2023]
Abstract
BACKGROUND Rotavirus group A (RVA) is a causative agent of acute gastroenteritis among young children worldwide, despite the global expansion of rotavirus vaccination. In Korea, although the prevalence of RVA has been reduced among young children owing to vaccination, nosocomial infections still occur among neonates. OBJECTIVES The aim of this study was to investigate the molecular epidemiology of RVA strains associated with several neonatal outbreaks in Seoul from 2017 to 2020. STUDY DESIGN Clinical and environmental samples were collected and screened for the presence of RVA using ELISA and PCR targeting VP6, respectively. RVA-positive strains were genotyped via RT-PCR and subsequent sequencing of VP4 and VP7 and were phylogenetically compared with RVA strains from other countries. RESULTS During 2017-2020, a total of 15 RVA outbreaks occurred at neonatal facilities (six in hospital neonatal wards and nine in postpartum care centers) in Seoul, and only two RVA genotypes were detected: G4P[6] and G8P[6]. G8P[6] emerged in Seoul November 2018 and immediately became the predominant genotype among neonates, at least up to 2020. Phylogenetic analysis revealed that the G8P[6] genotype in this study was closely related to G8P[6] strains first identified in Korea in 2017, but differed from G8P[6] strains detected in Africa. CONCLUSIONS A novel G8P[6] genotype of RVA strains has emerged and caused outbreaks among neonates in Seoul. Continued surveillance for circulating RVA genotypes is imperative to monitor genotype changes and their potential risks to public health.
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Affiliation(s)
- Jin Seok Kim
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea.
| | - Hyo-Won Jeong
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea
| | - Sook Hyun Park
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea
| | - Jin-Ah Kim
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea
| | - Young Hee Jin
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea
| | - Hyun Soo Kim
- Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Gyeonggi-do, Republic of Korea
| | - Soyoung Jung
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea
| | - Jae In Lee
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea
| | - Jib-Ho Lee
- Emerging Infectious Diseases Team, Seoul Metropolitan Government Research Institute of Public Health and Environment, Gyeonggi-do, Republic of Korea
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Yoon HS, Lim J, Sohn YH, Kim SY. Incidence, Clinical Characteristics, and Genotype Distribution of Rotavirus in a Neonatal Intensive Care Unit 5 Years After Introducing Rotavirus Vaccine. Front Pediatr 2022; 10:850839. [PMID: 35252070 PMCID: PMC8893347 DOI: 10.3389/fped.2022.850839] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 01/25/2022] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Rotavirus (RV) is a common cause of viral gastroenteritis in children worldwide. We aimed to investigate the incidence, symptoms, and genotype of RV infection in a neonatal intensive care unit (NICU) in South Korea 5 years after the introduction of RV vaccination to evaluate its effect on newborn infants. METHODS A total of 431 fecal specimens were collected from patients admitted to NICU between April 20, 2012 and September 10, 2013. Enzyme-linked immunoassays were used to detect RV antigen. Nested multiplex polymerase chain reaction was used for genotyping. RESULTS The overall incidence of RV infection was 43.9% and was significantly higher in preterm infants, infants born in the study hospital, low birth weight infants, and cesarean births (P < 0.05). Symptoms of diarrhea, poor feeding, abdominal distension, and apnea were significantly higher in infants with RV infection than those without infection. RV infection gradually increased depending on infant care at home, postpartum clinic, or hospital (26.0, 45.1, and 60.2%, respectively; P = 0.000). The dominant RV genotype in the NICU was G4P[6] at 95.4%. CONCLUSION Current RV vaccines did not affect the incidence of RV infection in newborn and preterm infants in the NICU. Most RV-positive patients in the NICU had symptoms, and the incidence of RV infection was relatively higher in hospitals and postpartum clinics with group life than home. The dominant RV genotype was G4P[6] across study groups.
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Affiliation(s)
- Hye Sun Yoon
- Department of Pediatrics, Nowon Eulji Medical Center, Eulji University School of Medicine, Seoul, South Korea
| | - Jiseun Lim
- Department of Preventive Medicine, Eulji University School of Medicine, Daejeon, South Korea
| | | | - Seung Yeon Kim
- Uijeongbu Eulji Medical Center, Eulji University School of Medicine, Uijeongbu, South Korea
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Tacharoenmuang R, Guntapong R, Upachai S, Singchai P, Fukuda S, Ide T, Hatazawa R, Sutthiwarakom K, Kongjorn S, Onvimala N, Luechakham T, Ruchusatsawast K, Kawamura Y, Sriwanthana B, Motomura K, Tatsumi M, Takeda N, Yoshikawa T, Murata T, Uppapong B, Taniguchi K, Komoto S. Full genome-based characterization of G4P[6] rotavirus strains from diarrheic patients in Thailand: Evidence for independent porcine-to-human interspecies transmission events. Virus Genes 2021; 57:338-357. [PMID: 34106412 DOI: 10.1007/s11262-021-01851-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 04/17/2021] [Indexed: 12/18/2022]
Abstract
The exact evolutionary patterns of human G4P[6] rotavirus strains remain to be elucidated. Such strains possess unique and strain-specific genotype constellations, raising the question of whether G4P[6] strains are primarily transmitted via independent interspecies transmission or human-to-human transmission after interspecies transmission. Two G4P[6] rotavirus strains were identified in fecal specimens from hospitalized patients with severe diarrhea in Thailand, namely, DU2014-259 (RVA/Human-wt/THA/DU2014-259/2014/G4P[6]) and PK2015-1-0001 (RVA/Human-wt/THA/PK2015-1-0001/2015/G4P[6]). Here, we analyzed the full genomes of the two human G4P[6] strains, which provided the opportunity to study and confirm their evolutionary origin. On whole genome analysis, both strains exhibited a unique Wa-like genotype constellation of G4-P[6]-I1-R1-C1-M1-A8-N1-T1-E1-H1. The NSP1 genotype A8 is commonly found in porcine rotavirus strains. Furthermore, on phylogenetic analysis, each of the 11 genes of strains DU2014-259 and PK2015-1-0001 appeared to be of porcine origin. On the other hand, the two study strains consistently formed distinct clusters for nine of the 11 gene segments (VP4, VP6, VP1-VP3, and NSP2-NSP5), strongly indicating the occurrence of independent porcine-to-human interspecies transmission events. Our observations provide important insights into the origin of zoonotic G4P[6] strains, and into the dynamic interaction between porcine and human rotavirus strains.
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Affiliation(s)
- Ratana Tacharoenmuang
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Ratigorn Guntapong
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Sompong Upachai
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Phakapun Singchai
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Saori Fukuda
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Tomihiko Ide
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Riona Hatazawa
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Karun Sutthiwarakom
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Santip Kongjorn
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Napa Onvimala
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Tipsuda Luechakham
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | | | - Yoshiki Kawamura
- Department of Pediatrics, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Busarawan Sriwanthana
- Medical Sciences Technical Office, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Kazushi Motomura
- Thailand-Japan Research Collaboration Center on Emerging and Re-Emerging Infections, Nonthaburi, 11000, Thailand
- Osaka Institute of Public Health, Osaka, 537-0025, Japan
| | - Masashi Tatsumi
- Thailand-Japan Research Collaboration Center on Emerging and Re-Emerging Infections, Nonthaburi, 11000, Thailand
| | - Naokazu Takeda
- Thailand-Japan Research Collaboration Center on Emerging and Re-Emerging Infections, Nonthaburi, 11000, Thailand
| | - Tetsushi Yoshikawa
- Department of Pediatrics, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Takayuki Murata
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Ballang Uppapong
- National Institute of Health, Department of Medical Sciences, Nonthaburi, 11000, Thailand
| | - Koki Taniguchi
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan
| | - Satoshi Komoto
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi, 470-1192, Japan.
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Socioeconomic Impact of the Rotavirus Vaccine in Korea: Comparing the Epidemiologic and Economic Characteristics of Rotavirus Gastroenteritis Before and After the Introduction of Vaccines. Pediatr Infect Dis J 2020; 39:460-465. [PMID: 31990891 DOI: 10.1097/inf.0000000000002582] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Since the introduction of 2 rotavirus (RV) vaccines in Korea, the vaccination rate has reached over 80% with out-of-pocket spending in the private market. We investigated the socioeconomic impact of RV vaccines in Korea to assess their value and public health contribution. METHODS By using National Health Insurance Service claims data, we compared the epidemiologic and economic characteristics of rotavirus gastroenteritis (RVGE) before and after the introduction of RV vaccines. For each year of the study period, the annual prevalence and national costs of RVGE were estimated based on children under 5 years with at least 1 National Health Insurance Service claims record with a diagnosis of RVGE. RESULTS Compared with the prevaccination period, the prevalence of RVGE decreased in the postvaccination period by 48.9% from 2097 per 100,000 children in 2006 to 1072 per 100,000 children in 2015, implying an increase in the vaccination rate and the prevention effect of the vaccines. The highest reduction was observed among those 12 to <24 months of age (-73.4%), presumably due to the benefit of full vaccination, while children under 2 months, ineligible for the RV vaccine, showed an increase (41.7%). The number of hospitalized RVGE cases per year decreased by 69.0%. The national economic burden of RVGE decreased by 28.6%. CONCLUSIONS The substantial reduction in the socioeconomic burden of RVGE after the introduction of RV vaccines confirms their benefit to society. This study would help health policy makers make empirical decisions on incorporating the vaccination into national immunization programs.
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Lee SK, Choi S, Kim JS, Lee EJ, Hyun J, Kim HS. Whole-genome analysis of rotavirus G4P[6] strains isolated from Korean neonates: association of Korean neonates and rotavirus P[6] genotypes. Gut Pathog 2019; 11:37. [PMID: 31333764 PMCID: PMC6621965 DOI: 10.1186/s13099-019-0318-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 07/06/2019] [Indexed: 12/20/2022] Open
Abstract
Background Group A rotaviruses are the major causative agents of pediatric gastroenteritis worldwide. Several studies have reported the predominance of G4P[6] rotavirus genotypes in Korean neonates, which is uncommon in other countries. Therefore, the purposes of this study were to determine the genotype constellations of complete genomes of G4P[6] rotavirus strains isolated from Korean neonates using next-generation sequencing, to compare these sequences with other G4P[6] strains in other countries, and to determine the reason for the predominance of G4P[6] genotypes in Korean neonates. Results Twenty rotavirus G4P[6] strains, isolated from January 2013 to January 2016, were selected for whole-genome sequencing. Eleven rotavirus genes were amplified using specific primer sets, and sequencing was carried out using an Ion S5 XL next-generation sequencing platform. Genotypes of each gene were determined, and phylogenetic analyses were performed to investigate genetic distances between genes of rotaviruses in this study and those of other rotavirus G4P[6] strains whose whole-genome sequences were previously published. All 20 rotavirus strains in this study had the same genotype: G4-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1, representing the Wa-like genotype constellation. BLAST searches of 20 G4P[6] rotavirus strains revealed that all G4 sequences in this study showed the highest nucleotide identity to G4 sequences of G4P[6] rotavirus strains isolated in Korea in 2008 (GenBank accession number: FJ603447). Additionally, P[6] gene sequences in this study showed the highest nucleotide identity to P[6] sequences of G4P[6] strains detected in Korea in 2002 (AY158093). Phylogenetic and nucleotide sequence analyses showed that G4P[6] strains in this study and previously reported G4P[6] strains in Korea were mostly detected in neonates and had similar G4 and P[6] sequences compared with other G4P[6] strains detected in other countries. Conclusions This study showed that the whole-genome constellation of rotavirus G4P[6] strains from Korean neonates resembled a Wa-like genotype constellation. Additionally, rotavirus genotypes detected in Korean neonates had unique P[6] sequences, which may be the cause of Korean neonatal rotavirus infection. Electronic supplementary material The online version of this article (10.1186/s13099-019-0318-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Su-Kyung Lee
- 1Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, 7, Keunjaebong-gil, Hwaseong-si, Gyeonggi-Do, 18450 South Korea
| | - Seoheui Choi
- 2Department of Pediatrics, Hallym University Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, 7, Keunjaebong-gil, Hwaseong-si, Gyeonggi-Do, 18450 South Korea
| | - Jae-Seok Kim
- 3Department of Laboratory Medicine, Kangdong Sacred Heart Hospital, College of Medicine, Hallym University, 150, Seongan-ro, Gangdong-gu, Seoul, 05355 South Korea
| | - Eun Jin Lee
- 1Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, 7, Keunjaebong-gil, Hwaseong-si, Gyeonggi-Do, 18450 South Korea
| | - Jungwon Hyun
- 1Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, 7, Keunjaebong-gil, Hwaseong-si, Gyeonggi-Do, 18450 South Korea
| | - Hyun Soo Kim
- 1Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, College of Medicine, Hallym University, 7, Keunjaebong-gil, Hwaseong-si, Gyeonggi-Do, 18450 South Korea
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Yahiro T, Takaki M, Chandrasena TGAN, Rajindrajith S, Iha H, Ahmed K. Human-porcine reassortant rotavirus generated by multiple reassortment events in a Sri Lankan child with diarrhea. INFECTION GENETICS AND EVOLUTION 2018; 65:170-186. [PMID: 30055329 DOI: 10.1016/j.meegid.2018.07.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 07/11/2018] [Accepted: 07/12/2018] [Indexed: 01/22/2023]
Abstract
A human-porcine reassortant rotavirus, strain R1207, was identified from 74 group A rotaviruses detected in 197 (37.6%) stool samples collected from patients who attended a tertiary care hospital in Ragama, Sri Lanka. This is the first report of a human-porcine reassortant rotavirus in Sri Lanka. The patient was a 12-month-old boy who had been hospitalized with fever and acute diarrhea with a duration of 6 days. The family had pigs at home before the birth of this boy. However, the neighbors still practice pig farming. The genotype constellation of R1207 was G4-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1. This is based on the assignment of all the eleven gene segments a full genome-based genotyping system. R1207 showed a 4-2-3-2 genomic electrophoretic migration pattern, which is characteristic of group A rotaviruses. Our analyses revealed that five (NSP2, NSP4, VP1, VP2, and VP7) of the 11 genes were closely related to the respective genes of porcine strains. Although the remaining six genes (NSP1, NSP3, NSP5, VP3, VP4, and VP6) were related to human strains, with the exception of the gene sequence of NSP1, all of these human strains were human-porcine reassortants. With a genogroup 1 genetic backbone, this strain was possibly formed via multiple genetic reassortments. We do not know whether this strain is circulating in pigs, as no data are available on porcine rotaviruses in Sri Lanka. Surveillance should be strengthened to determine the epidemiology of this genotype of rotavirus in Sri Lanka and to assess whether the infection was limited or sustained by ongoing human-to-human transmission.
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Affiliation(s)
- Takaaki Yahiro
- Department of Pathobiology and Medical Diagnostics, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia
| | - Minako Takaki
- Department of Microbiology, Oita University, Yufu-shi, Oita, Japan
| | | | | | - Hidekatsu Iha
- Department of Microbiology, Oita University, Yufu-shi, Oita, Japan
| | - Kamruddin Ahmed
- Department of Pathobiology and Medical Diagnostics, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia; Borneo Medical and Health Research Centre, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia.
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Abstract
Background Rotaviruses are the major causes of pediatric gastroenteritis worldwide. The genotypic distribution of rotavirus strains shows temporal and geographical fluctuations, and knowledge of the molecular epidemiology of rotaviruses is important for the development of vaccines and diagnostic reagents. We investigated VP4 and VP7 capsid genotypes of rotaviruses isolated from 211 stool specimens collected from Korean neonates in a neonatal intensive care unit from September 2017 to March 2018. Results Of 211 stool specimens, 15 specimens (7.1%) were rotavirus-positive. Eleven specimens (73.3%) were G8P[6] type and 4 (26.7%) were G4P[6] type. Sequence analysis revealed that all G8 sequences in this study showed the highest nucleotide identity to G8 sequences of G8P[8] rotavirus strains isolated in Vietnam in 2014, and P[6] gene sequences showed the highest nucleotide identity to P[6] sequences of G4P[6] strains detected in Korea in 2012. Only one amino acid difference in VP7 was found in 3 of the 11 G8P[6] strains in this study, but multiple amino acid substitutions in VP7 were detected between these G8P[6] strains and the commonly used vaccine strains. Conclusions This study showed that rotavirus G8P[6] strains were firstly detected at high frequency in Korean neonates from September 2017 to March 2018. These new rotavirus G8P[6] strains were estimated to be derived from reassortment events between the G8 of G8P[8] strains in Asian region and the P[6] of G4[6] in Korea. Whether the emergence of this unusual G8P[6] strain reflects continuous prevalence or transient occurrence will require continuous monitoring of rotavirus epidemiology.
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