Xiaogen Dong1, Meng Qin2, Zhao-E Wang3, Xiaoxing Yang4, Qingrui Wu5, Huiru Feng6, Xiuxia Wei7, Hong Yu8, Jinsong Li9, Jie Li1. 1. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: wjkftcdc@163.com. 2. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: alex2003@yeah.net. 3. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: 1980554637@qq.com. 4. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: 285775687@qq.com. 5. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: 20361060@qq.com. 6. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: 756193832@qq.com. 7. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: 493981518@qq.com. 8. Fengtai District Center for Disease Control and Prevention of Beijing, 3 Xi An St., Feng-Tai District, Beijing, 100071, China. Electronic address: 258241703@qq.com. 9. China CDC, National Institute for Viral Disease Control and Prevention, 100 Ying-Xin St., Xuan-Wu District, Beijing, 100052, China. Electronic address: lionalex@126.com.
Abstract
BACKGROUND: Recombinant norovirus strain GII.P7/GII.6 has been circulating in Asia and around the world for at least 20 years, but has been responsible for relatively few outbreaks. METHODS: We used statistical analyses, real-time reverse transcription - PCR, and genome sequence analyses to investigate an outbreak of gastroenteritis, identifying the pathogen, the risk factors associated with the outbreak, and the molecular features of GII.P7/GII.6 strains. RESULTS: An outbreak of gastroenteritis was reported at a school involving 12 students and lasting 6 days, from September 13 to September 18, 2017. Epidemiological studies suggested that norovirus was transmitted from person to person and not via contaminated food or drinking water in this outbreak. Using a sequence analysis of the junction region between open reading frames 1 and 2, the pathogen was identified as a recombinant norovirus (strain GII.P7/GII.6). The full-length genome of the outbreak strain shared 86%-97% identity with those of other GII.P7/GII.6 strains. Phylogenetic trees were constructed from partial open reading frame 1 (ORF1) and ORF2 sequences from the outbreak strain and GII.P7/GII.6 norovirus sequences available in GenBank. On the ORF1 tree, the partial sequences of ORF1 were grouped into cluster A (with GII.6), cluster B (with GII.7), and a separate cluster (C), based on the GII.6 and GII.7 reference strains. The ORF2 tree showed all GII.P7/GII.6 strains formed a cluster together with GII.6 strains. Amino-acid substitutions and insertions/deletions were common in the capsid protein, especially in it's P2 and P1 domains. The outbreak was controlled within several days using appropriate measures. CONCLUSIONS: Because it may play a prominent role in future outbreaks, recombinant norovirus strain GII.P7/GII.6 should be monitored with routine surveillance.
BACKGROUND: Recombinant norovirus strain GII.P7/GII.6 has been circulating in Asia and around the world for at least 20 years, but has been responsible for relatively few outbreaks. METHODS: We used statistical analyses, real-time reverse transcription - PCR, and genome sequence analyses to investigate an outbreak of gastroenteritis, identifying the pathogen, the risk factors associated with the outbreak, and the molecular features of GII.P7/GII.6 strains. RESULTS: An outbreak of gastroenteritis was reported at a school involving 12 students and lasting 6 days, from September 13 to September 18, 2017. Epidemiological studies suggested that norovirus was transmitted from person to person and not via contaminated food or drinking water in this outbreak. Using a sequence analysis of the junction region between open reading frames 1 and 2, the pathogen was identified as a recombinant norovirus (strain GII.P7/GII.6). The full-length genome of the outbreak strain shared 86%-97% identity with those of other GII.P7/GII.6 strains. Phylogenetic trees were constructed from partial open reading frame 1 (ORF1) and ORF2 sequences from the outbreak strain and GII.P7/GII.6 norovirus sequences available in GenBank. On the ORF1 tree, the partial sequences of ORF1 were grouped into cluster A (with GII.6), cluster B (with GII.7), and a separate cluster (C), based on the GII.6 and GII.7 reference strains. The ORF2 tree showed all GII.P7/GII.6 strains formed a cluster together with GII.6 strains. Amino-acid substitutions and insertions/deletions were common in the capsid protein, especially in it's P2 and P1 domains. The outbreak was controlled within several days using appropriate measures. CONCLUSIONS: Because it may play a prominent role in future outbreaks, recombinant norovirus strain GII.P7/GII.6 should be monitored with routine surveillance.
Authors: Rory J Tinker; Antonio Charlys da Costa; Roozbeh Tahmasebi; Eric Delwart; Ester Cerdeira Sabino; Elcio Leal; Adriana Luchs; Flavio Augusto de Pádua Milagres; Vanessa Dos Santos Morais; Ramendra Pati Pandey; Alexis José-Abrego; Rafael Brustulin; Maria da Aparecida Rodrigues Teles; Mariana Sequetin Cunha; Emerson Luiz Lima Araújo; Mariela Martínez Gómez; Xutao Deng Journal: Arch Virol Date: 2021-01-19 Impact factor: 2.574