2022 Vol.37(5)

Rotavirus is the leading pathogen that causes severe gastroenteritis in children and infects virtually all children under five years old. Currently only two rotavirus vaccines are licensed in the Chinese market, but the predominant serotypes of epidemic rotavirus are constantly changing. Based on the bovine rotavirus UK Compton strain, a human-bovine reassortant hexavalent rotavirus vaccine (HRV) containing epidemic serotypes G1, G2, G3, G4, G8 and G9 was developed. And phase I and phase II clinical trials showed that this oral hexavalent rotavirus vaccine was well-tolerated and highly immunogenic in infants. In this issue, the subsequent randomized, double-blind, placebo-controlled multicenter phase III trial is reported. Results show that the HRV provides high efficacy against severe rotavirus gastroenteritis (RVGE) and RVGE hospitalization regardless of serotype, without adverse events compared to the placebo group. The cover image shows a shield formed by the hexavalent rotavirus vaccine protecting the infant against the rotavirus infection. See page 724–730 for details.

Research Article

Epidemiological characteristics and disease burden of infectious mononucleosis in hospitalized children in China: A nationwide retrospective study

Mengjia Liu, Xinyu Wang, Linlin Zhang, Guoshuang Feng, Yueping Zeng, Ran Wang, Zhengde Xie

2022, 37(5): 637 doi: 10.1016/j.virs.2022.07.007

Received: 15 February 2022 Accepted: 07 July 2022
Abstract [PDF 1204 KB] ScienceDirectESM
Epstein-Barr virus (EBV) is very common, with the infection rate in adults over 90% worldwide. Infectious mononucleosis (IM) is caused by primary infection with EBV. Most IM patients are generally considered to have a favorable prognosis, but a few patients will also develop complications. Children with severe symptoms will require hospitalization. However, the disease burden of children hospitalized with IM in China has been rarely described. In this study, we included the Face sheets of discharge medical records from 27 member children's hospitals of Futang Research Center of Pediatric Development from Jan 1st, 2016 to Dec 31st, 2020, and medical information such as gender, age, region, time of admission, length of stay and expenditure were extracted. There were 24,120 IM cases, which accounted for 0.42% (24,120/5,693,262) of all hospitalized cases during this period. The ratio of male to female was 1.48:1. Hospitalization for IM in the 4–6 years age group was the highest among inpatients of all age groups. Case numbers increased year by year between 2016 and 2020, and the monthly hospitalization was generally high from Jul to Sep but reduced from Jan to Feb per year. Bronchitis/pneumonia and hepatic dysfunction were two common complications in hospitalized IM patients. The median length of stay was 8 days, and the median cost of hospitalization was 970.59 US dollars. This study will help understand the epidemiological characteristics and disease burden of hospitalized children with IM in China.

Isolation and oral immunogenicity assessment of porcine epidemic diarrhea virus NH-TA2020 strain: One of the predominant strains circulating in China from 2017 to 2021

Xiaowen Li, Yang Li, Jiapei Huang, Yali Yao, Wenying Zhao, Yunjing Zhang, Jie Qing, Jing Ren, Zhong Yan, Zewei Wang, Xiaofang Hu, Duli Kang, Hongqiang Liu, Zhichun Yan

2022, 37(5): 646 doi: 10.1016/j.virs.2022.08.002

Received: 14 March 2022 Accepted: 02 August 2022
Abstract [PDF 3835 KB] ScienceDirectESM
Porcine epidemic diarrhea (PED) caused by porcine epidemic diarrhea virus (PEDV) is one of the most devastating diseases in the global pig industry due to its high mortality rate in piglets. Maternal vaccines can effectively enhance the gut-mammary gland-secretory IgA axis to boost lactogenic immunity and passive protection of nursing piglets against PEDV challenge. From 2017 to 2021, we collected 882 diarrhea samples from 303 farms in China to investigate the epidemiology of PEDV. The result showed that about 52.15% (158/303) of the farms were positive for PEDV with an overall detection rate of 63.95% (564/882) of the samples. The S1 fragments of S gene from 104 strains were sequenced for the phylogenetic analysis. A total of 71 PEDV strains (68.27%) sequenced in this study were clustered into the predominant G2c subgroup, while the newly-defined G2d strains (9.62%) were identified in three provinces of China. The NH-TA2020 strain of G2c subgroup was isolated and cultured, and its infection to piglets caused watery diarrhea within 24 h, indicating its strong pathogenicity. Oral administration of NH-TA2020 strain to pregnant gilts stimulated high levels of IgA antibody in colostrum. The piglets fed by the gilts above were challenged with NH-TA2020 strain or CH–HeB-RY-2020 strain from G2d subgroup, and the clinical symptoms and virus shedding were significantly reduced compared to the mock group. Our findings suggest that G2c subgroup is the predominant branch circulating in China from 2017 to 2021. Oral administration of NH-TA2020 enhances maternal IgA and lactogenic immune responses, which confer protection against the homologous and emerging G2d PEDV strains challenges in neonates.

The nonstructural protein 2C of Coxsackie B virus has RNA helicase and chaperoning activities

Ziyu Chen, Xiaobei Xiong, Yiyang Li, Muhan Huang, Yujie Ren, Di Wu, Yang Qiu, Mingzhou Chen, Ting Shu, Xi Zhou

2022, 37(5): 656 doi: 10.1016/j.virs.2022.05.004

Received: 30 March 2022 Accepted: 10 May 2022
Abstract [PDF 1631 KB] ScienceDirectESM
RNA-remodeling proteins, including RNA helicases and chaperones, play vital roles in the remodeling of structured RNAs. During viral replication, viruses require RNA-remodeling proteins to facilitate proper folding and/or re-folding the viral RNA elements. Coxsackieviruses B3 (CVB3) and Coxsackieviruses B5 (CVB5), belonging to the genus Enterovirus in the family Picornaviridae, have been reported to cause various infectious diseases such as hand-foot-and-mouth disease, aseptic meningitis, and viral myocarditis. However, little is known about whether CVB3 and CVB5 encode any RNA remodeling proteins. In this study, we showed that 2C proteins of CVB3 and CVB5 contained the conserved SF3 helicase A, B, and C motifs, and functioned not only as RNA helicase that unwound RNA helix bidirectionally in an NTP-dependent manner, but also as RNA chaperone that remodeled structured RNAs and facilitated RNA strand annealing independently of NTP. In addition, we determined that the NTPase activity and RNA helicase activity of 2C proteins of CVB3 and CVB5 were dependent on the presence of divalent metallic ions. Our findings demonstrate that 2C proteins of CVBs possess RNA-remodeling activity and underline the functional importance of 2C protein in the life cycle of CVBs.

Transmembrane domain of IFITM3 is responsible for its interaction with influenza virus HA2 subunit

Wang Xu, Yuhang Wang, Letian Li, Xiaoyun Qu, Quan Liu, Tiyuan Li, Shipin Wu, Ming Liao, Ningyi Jin, Shouwen Du, Chang Li

2022, 37(5): 664 doi: 10.1016/j.virs.2022.07.002

Received: 06 April 2022 Accepted: 30 June 2022
Abstract [PDF 3915 KB] ScienceDirect
Interferon-inducible transmembrane protein 3 (IFITM3) inhibits influenza virus infection by blocking viral membrane fusion, but the exact mechanism remains elusive. Here, we investigated the function and key region of IFITM3 in blocking influenza virus entry mediated by hemagglutinin (HA). The restriction of IFITM3 on HA-mediated viral entry was confirmed by pseudovirus harboring HA protein from H5 and H7 influenza viruses. Subcellular co-localization and immunocoprecipitation analyses revealed that IFITM3 partially co-located with the full-length HA protein and could directly interact with HA2 subunit but not HA1 subunit of H5 and H7 virus. Truncated analyses showed that the transmembrane domain of the IFITM3 and HA2 subunit might play an important role in their interaction. Finally, this interaction of IFITM3 was also verified with HA2 subunits from other subtypes of influenza A virus and influenza B virus. Overall, our data demonstrate for the first time a direct interaction between IFITM3 and influenza HA protein via the transmembrane domain, providing a new perspective for further exploring the biological significance of IFITM3 restriction on influenza virus infection or HA-mediated antagonism or escape.

IFN-β1b induces OAS3 to inhibit EV71 via IFN-β1b/JAK/STAT1 pathway

Baisong Zheng, Xiaolei Zhou, Li Tian, Jian Wang, Wenyan Zhang

2022, 37(5): 676 doi: 10.1016/j.virs.2022.07.013

Received: 21 January 2022 Accepted: 27 July 2022
Abstract [PDF 2413 KB] ScienceDirectESM
Enterovirus 71 (EV71) caused hand, foot and mouth disease (HFMD) is a serious threat to the health of young children. Although type I interferon (IFN-I) has been proven to control EV71 replication, the key downstream IFN-stimulated gene (ISG) remains to be clarified and investigated. Recently, we found that 2'-5'-oligoadenylate synthetases 3 (OAS3), as one of ISG of IFN-β1b, was antagonized by EV71 3C protein. Here, we confirm that OAS3 is the major determinant of IFN-β1b-mediated EV71 inhibition, which depends on the downstream constitutive RNase L activation. 2'-5'-oligoadenylate (2-5A) synthesis activity deficient mutations of OAS3 D816A, D818A, D888A, and K950A lost resistance to EV71 because they could not activate downstream RNase L. Further investigation proved that EV71 infection induced OAS3 but not RNase L expression by IFN pathway. Mechanically, EV71 or IFN-β1b-induced phosphorylation of STAT1, but not STAT3, initiated the transcription of OAS3 by directly binding to the OAS3 promoter. Our works elucidate the immune regulatory mechanism of the host OAS3/RNase L system against EV71 replication.

Rottlerin plays an antiviral role at early and late steps of Zika virus infection

Shili Zhou, Quanshi Lin, Changbai Huang, Xiaotong Luo, Xu Tian, Chao Liu, Ping Zhang

2022, 37(5): 685 doi: 10.1016/j.virs.2022.07.012

Received: 12 March 2022 Accepted: 26 July 2022
Abstract [PDF 2082 KB] ScienceDirectESM
Infection of Zika virus (ZIKV) may cause microcephaly and other neurological disorders, while no vaccines and drugs are available. Our study revealed that rottlerin confers a broad antiviral activity against several enveloped viruses, including ZIKV, vesicular stomatitis virus, and herpes simplex virus, but not against two naked viruses (enterovirus 71 and encephalomyocarditis virus). Rottlerin does not have a direct virucidal effect on the virions, and its antiviral effect is independent of its regulation on PKCδ or ATP. Both pretreatment and post-treatment of rottlerin effectively reduce the viral replication of ZIKV. The pretreatment of rottlerin disturbs the endocytosis of enveloped viruses, while the post-treatment of rottlerin acts at a late stage through disturbing the maturation of ZIKV. Importantly, administration of rottlerin in neonatal mice significantly decreased the ZIKV replication in vivo, and alleviated the neurological symptoms caused by ZIKV. Our work suggests that rottlerin exerts an antiviral activity at two distinct steps of viral infection, and can be potentially developed as a prophylactic and therapeutic agent.

Comparison of viral propagation and drug response among SARS-CoV-2 VOCs using replicons capable of recapitulating virion assembly and release

Lingqian Tian, Qiuhong Liu, Rongjuan Pei, Yingshan Chen, Chonghui Xu, Jielin Tang, Hao Sun, Kunpeng Liu, Qi Yang, Lei Yang, Leshan Li, Yongli Zhang, Yuan Zhou, Chao Shan, Xue Hu, Xinwen Chen, Yun Wang

2022, 37(5): 695 doi: 10.1016/j.virs.2022.06.008

Received: 29 March 2022 Accepted: 27 June 2022
Abstract [PDF 1924 KB] ScienceDirectESM
Several variants of concern (VOCs) have emerged since the WIV04 strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first isolated in January 2020. Due to mutations in the spike (S) protein, these VOCs have evolved to enhance viral infectivity and immune evasion. However, whether mutations of the other viral proteins lead to altered viral propagation and drug resistance remains obscure. The replicon is a noninfectious viral surrogate capable of recapitulating certain steps of the viral life cycle. Although several SARS-CoV-2 replicons have been developed, none of them were derived from emerging VOCs and could only recapitulate viral genome replication and subgenomic RNA (sgRNA) transcription. In this study, SARS-CoV-2 replicons derived from the WIV04 strain and two VOCs (the Beta and Delta variants) were prepared by removing the S gene from their genomes, while other structural genes remained untouched. These replicons not only recapitulate viral genome replication and sgRNA transcription but also support the assembly and release of viral-like particles, as manifested by electron microscopic assays. Thus, the S-deletion replicon could recapitulate virtually all the post-entry steps of the viral life cycle and provides a versatile tool for measuring viral intracellular propagation and screening novel antiviral drugs, including inhibitors of virion assembly and release. Through the quantification of replicon RNA released into the supernatant, we demonstrate that viral intracellular propagation and drug response to remdesivir have not yet substantially changed during the evolution of SARS-CoV-2 from the WIV04 strain to the Beta and Delta VOCs.

Clinical characteristics of 310 SARS-CoV-2 Omicron variant patients and comparison with Delta and Beta variant patients in China

Wei Yang, Songliu Yang, Lei Wang, Yuxin Zhou, Yu Xin, Hongxu Li, Wenjing Mu, Qi Wu, Lei Xu, Mingyan Zhao, Changsong Wang, Kaijiang Yu

2022, 37(5): 704 doi: 10.1016/j.virs.2022.07.014

Received: 16 March 2022 Accepted: 29 July 2022
Abstract [PDF 848 KB] ScienceDirect
Although the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has spread, data on the clinical characteristics of infected patients are limited. In this study, the demographic, clinical characteristics, and laboratory data of 310 SARS-CoV-2 Omicron variant patients treated at Haihe Hospital of Tianjin were collected and analyzed. Information on these patients was compared to 96 patients with the Delta variant of concern (VOC) and 326 patients with the Beta VOC during the previous coronavirus disease 2019 (COVID-19) outbreak in Harbin. Of the 310 patients infected with the Omicron variant, the median age was 35 years. Most patients were clinically classified as mild (57.74%), and the most common symptoms were cough (48.71%), fever (39.35%), and sore throat (38.26%). The results for different vaccination groups in the Omicron group showed that the median of “SARS-CoV-2 specific IgG” after 2 or 3 doses of vaccination was higher than the unvaccinated group (all Ps < 0.05). Older age was associated with a higher proportion of moderate cases and lower asymptomatic and mild cases based on clinical classifications. Compared to the Delta and Beta groups, the median age of the Omicron group was younger. The total number of asymptomatic patients and mild patients in the Omicron virus group was higher than the Delta and Beta groups (60.97% vs. 54.17% vs. 47.55%). This study presented the clinical characteristics of the first group of patients infected with the Omicron variant in Tianjin, China, and compared their clinical features with patients infected by the Delta and Beta variants, which would increase our understanding of the characteristics of SARS-CoV-2 Omicron variant.

Seroprevalence of neutralizing antibodies against adenovirus type 26 and 35 in healthy populations from Guangdong and Shandong provinces, China

Haisu Yi, Qian Wang, Jiankai Deng, Hengchun Li, Yingkun Zhang, Zhilong Chen, Tianxin Ji, Wenming Liu, Xuehua Zheng, Qinghua Ma, Xinxin Sun, Yudi Zhang, Xuegao Yu, Mengzhang He, Ling Chen, Ying Feng

2022, 37(5): 716 doi: 10.1016/j.virs.2022.06.006

Received: 09 February 2022 Accepted: 21 June 2022
Abstract [PDF 1462 KB] ScienceDirectESM
Human adenoviruses type 26 (HAdV26) and type 35 (HAdV35) have increasingly become the choice of adenovirus vectors for vaccine application. However, the population pre-existing immunity to these two adenoviruses in China, which may reduce vaccine efficacy, remains largely unknown. Here, we established micro-neutralizing (MN) assays to investigate the seroprevalence of neutralizing antibodies (nAbs) against HAdV26 and HAdV35 in the general population of Guangdong and Shandong provinces, China. A total of 1184 serum samples were collected, 47.0% and 15.8% of which showed HAdV26 and HAdV35 nAb activity, respectively. HAdV26-seropositive individuals tended to have more moderate nAbs titers (201–1000), while HAdV35-seropositive individuals appeared to have more low nAbs titers (72–200). The seropositive rates of HAdV26 and HAdV35 in individuals younger than 20 years old were very low. The seropositive rates of HAdV26 increased with age before 70 years old and decreased thereafter, while HAdV35 seropositive rates did not show similar characteristics. Notably, the seropositive rates and nAb levels of both HAdV26 and HAdV35 were higher in Guangdong Province than in Shandong Province, but did not exert significant differences between males and females. The seroprevalence between HAdV26 and HAdV35 showed little correlation, and no significant cross-neutralizing activity was detected. These results clarified the characteristics of the herd immunity against HAdV26 and HAdV35, and provided information for the rational development and application of HAdV26 and HAdV35 as vaccine vectors in China.

Efficacy, safety and immunogenicity of hexavalent rotavirus vaccine in Chinese infants

Zhiwei Wu, Qingliang Li, Yan Liu, Huakun Lv, Zhaojun Mo, Fangjun Li, Qingchuan Yu, Fei Jin, Wei Chen, Yong Zhang, Teng Huang, Xiaosong Hu, Wei Xia, Jiamei Gao, Haisong Zhou, Xuan Bai, Yueyue Liu, Zhenzhen Liang, Zhijun Jiang, Yingping Chen, Jiuwei Zhang, Jialiang Du, Biao Yang, Bo Xing, Yantao Xing, Ben Dong, Qinghai Yang, Chen Shi, Tingdong Yan, Bo Ruan, Haiyun Shi, Xingliang Fan, Dongyang Feng, Weigang Lv, Dong Zhang, Xiangchu Kong, Liuyifan Zhou, Dinghong Que, Hong Chen, Zhongbing Chen, Xiang Guo, Weiwei Zhou, Cong Wu, Qingrong Zhou, Yuqing Liu, Jian Qiao, Ying Wang, Xinguo Li, Kai Duan, Yuliang Zhao, Gelin Xu, Xiaoming Yang

2022, 37(5): 724 doi: 10.1016/j.virs.2022.07.011

Received: 16 April 2022 Accepted: 19 July 2022
Abstract [PDF 664 KB] ScienceDirect
A randomized, double-blind, placebo-controlled multicenter trial was conducted in healthy Chinese infants to assess the efficacy and safety of a hexavalent live human-bovine reassortant rotavirus vaccine (HRV) against rotavirus gastroenteritis (RVGE). A total of 6400 participants aged 6–12 weeks were enrolled and randomly assigned to either HRV (n = 3200) or placebo (n = 3200) group. All the subjects received three oral doses of vaccine four weeks apart. The vaccine efficacy (VE) against RVGE caused by rotavirus serotypes contained in HRV was evaluated from 14 days after three doses of administration up until the end of the second rotavirus season. VE against severe RVGE, VE against RVGE hospitalization caused by serotypes contained in HRV, and VE against RVGE, severe RVGE, and RVGE hospitalization caused by natural infection of any serotype of rotavirus were also investigated. All adverse events (AEs) were collected for 30 days after each dose. Serious AEs (SAEs) and intussusception cases were collected during the entire study. Our data showed that VE against RVGE caused by serotypes contained in HRV was 69.21% (95%CI: 53.31–79.69). VE against severe RVGE and RVGE hospitalization caused by serotypes contained in HRV were 91.36% (95%CI: 78.45–96.53) and 89.21% (95%CI: 64.51–96.72) respectively. VE against RVGE, severe RVGE, and RVGE hospitalization caused by natural infection of any serotype of rotavirus were 62.88% (95%CI: 49.11–72.92), 85.51% (95%CI: 72.74–92.30) and 83.68% (95%CI: 61.34–93.11). Incidences of AEs from the first dose to one month post the third dose in HRV and placebo groups were comparable. There was no significant difference in incidences of SAEs in HRV and placebo groups. This study shows that this hexavalent reassortant rotavirus vaccine is an effective, well-tolerated, and safe vaccine for Chinese infants.

LNP-CpG ODN-adjuvanted varicella-zoster virus glycoprotein E induced comparable levels of immunity with ShingrixTM in VZV-primed mice

Ning Luan, Han Cao, Yunfei Wang, Kangyang Lin, Cunbao Liu

2022, 37(5): 731 doi: 10.1016/j.virs.2022.06.002

Received: 02 March 2022 Accepted: 01 June 2022
Abstract [PDF 2361 KB] ScienceDirect
Latent varicella-zoster virus (VZV) may be reactivated to cause herpes zoster, which affects one in three people during their lifetime. The currently available subunit vaccine ShingrixTM is superior to the attenuated vaccine Zostavax® in terms of both safety and efficacy, but the supply of its key adjuvant component QS21 is limited. With ionizable lipid nanoparticles (LNPs) that were recently approved by the FDA for COVID-19 mRNA vaccines as carriers, and oligodeoxynucleotides containing CpG motifs (CpG ODNs) approved by the FDA for a subunit hepatitis B vaccine as immunostimulators, we developed a LNP vaccine encapsulating VZV-glycoprotein E (gE) and CpG ODN, and compared its immunogenicity with ShingrixTM in C57BL/6J mice. The results showed that the LNP vaccine induced comparable levels of gE-specific IgG antibodies to ShingrixTM as determined by enzyme-linked immunosorbent assay (ELISA). Most importantly, the LNP vaccine induced comparable levels of cell-mediated immunity (CMI) that plays decisive roles in the efficacy of zoster vaccines to ShingrixTM in a VZV-primed mouse model that was adopted for preclinical studies of ShingrixTM. Number of IL-2 and IFN-γ secreting splenocytes and proportion of T helper 1 (Th1) cytokine-expressing CD4+ T cells in LNP-CpG-adjuvanted VZV-gE vaccinated mice were similar to that of ShingrixTM boosted mice. All of the components in this LNP vaccine can be artificially and economically synthesized in large quantities, indicating the potential of LNP-CpG-adjuvanted VZV-gE as a more cost-effective zoster vaccine.

The infectivity and pathogenicity of hepatitis A virus live-attenuated vaccine strain H2 in type I interferon receptor-deficient mice

Qing-Qing Ma, Hong-Jiang Wang, Jian Li, Meng-Qi Li, Tian-Shu Cao, Xiao-Yan Wu, Hong-Ying Qiu, Hui Zhao, Cheng-Feng Qin

2022, 37(5): 740 doi: 10.1016/j.virs.2022.07.009

Received: 22 April 2022 Accepted: 23 May 2022
Abstract [PDF 1346 KB] ScienceDirectESM
Hepatitis A virus (HAV) live-attenuated vaccine H2 strain has been approved for clinical use for decades with ideal safety profiles in nonhuman primate models and humans. Recently, type I interferon (IFN) receptor-deficient mice were shown to be susceptible to HAV infection. Herein, we sought to determine the infection and replication dynamics of the H2 in Ifnar-/- mice that lack type I IFN receptor. Following intravenous injection, the H2 failed to cause obvious clinical symptoms in Ifnar-/- mice, and no significant upregulation in serum alanine aminotransferase (ALT) levels was observed. Notably, the histopathological examination showed that there were significant focal infiltrations of lymphocytes and neutrophils in the portal area, but no focal necrosis was observed in liver tissues. Viral RNAs sustained in the liver, and the infectious virus could be recovered from the liver tissue until 42 days post-infection. More importantly, H2 infection induced obvious viremia and persistent viral shedding in feces. In addition, robust HAV-specific humoral immune responses were induced in Ifnar-/- mice. Overall, our study revealed the safety profile of H2 in Ifnar-/- mice, which not only helps understand the attenuation mechanism of H2, but also expands the application of the Ifnar-/--/- mouse model for HAV studies.

A multiple-target mRNA-LNP vaccine induces protective immunity against experimental multi-serotype DENV in mice

Lihong He, Wenqiang Sun, Limin Yang, Wenjun Liu, Jing Li

2022, 37(5): 746 doi: 10.1016/j.virs.2022.07.003

Received: 15 April 2022 Accepted: 04 July 2022
Abstract [PDF 1994 KB] ScienceDirectESM
Dengue virus (DENV) is a mosquito-borne virus with a rapid spread to humans, causing mild to potentially fatal illness in hundreds of millions of people each year. Due to the large number of serotypes of the virus, there remains an unmet need to develop protective vaccines for a broad spectrum of the virus. Here, we constructed a modified mRNA vaccine containing envelope domain III (E-DIII) and non-structural protein 1 (NS1) coated with lipid nanoparticles. This multi-target vaccine induced a robust antiviral immune response and increased neutralizing antibody titers that blocked all four types of DENV infection in vitro without significant antibody-dependent enhancement (ADE). In addition, there was more bias for Th1 than Th2 in the exact E-DIII and NS1-specific T cell responses after a single injection. Importantly, intramuscular immunization limited DENV transmission in vivo and eliminated vascular leakage. Our findings highlight that chimeric allogeneic structural and non-structural proteins can be effective targets for DENV vaccine and that they can prevent the further development of congenital DENV syndrome.
Letter

New discovery of high-affinity SARS-CoV-2 spike S2 protein binding peptide selected by PhIP-Seq

Mengyuan Chen, Shuizhen He, Hualong Xiong, Dongxu Zhang, Shaojuan Wang, Wangheng Hou, Xiaomei Zhu, Jin Wang, Yang Huang, Congming Hong, Yubin Wu, Ruoyao Qi, Tianying Zhang, Quan Yuan, Tingdong Li, Yixin Chen, Shiyin Zhang, Shengxiang Ge, Jun Zhang, Ningshao Xia

2022, 37(5): 758 doi: 10.1016/j.virs.2022.07.001

Received: 28 July 2021 Accepted: 30 June 2022
Abstract [PDF 1227 KB] ScienceDirectESM
Highlights
1 A peptide Spep-1 targeting S2 of SARS-CoV-2 spike protein was selected by PhIP-Seq.
2 Spep-1 showed nanomolar affinity and high specificity to spike protein.
3 S-1 based immunoassay can detect femtomolar spike antigen in spiked serum samples.
4 Spep-1 can be used in future on S2 recognition, virus tracing and drug delivery.

Similar aerosol emission rates and viral loads in upper respiratory tracts for COVID-19 patients with Delta and Omicron variant infection

Jiaming Li, Yidun Zhang, Lina Jiang, Hongliang Cheng, Jingjing Li, Li Li, Zehui Chen, Fei Tang, Yingying Fu, Yifei Jin, Bing Lu, Jing Zheng, Zhongyi Wang

2022, 37(5): 762 doi: 10.1016/j.virs.2022.07.010

Received: 10 November 2021 Accepted: 19 July 2022
Abstract [PDF 610 KB] ScienceDirectESM
Highlights
1 Aerosol emission rates of Delta or Omicron patients were similar.
2 Viral loads in upper respiratory tract of Alpha, Delta and Omicron patients were similar.
3 Viral loads in upper respiratory tract of vaccinated or unvaccinated Delta patients had no difference.

HCV 6a was expanding and became the predominant subtype among blood donors between 2004 and 2019 in Guangdong, China

Rongsong Du, Ru Xu, Jieting Huang, Hao Wang, Min Wang, Qiao Liao, Zhengang Shan, Huishan Zhong, Yourong Zheng, Xia Rong, Yongshui Fu

2022, 37(5): 765 doi: 10.1016/j.virs.2022.07.005

Received: 07 October 2021 Accepted: 15 June 2022
Abstract [PDF 1170 KB] ScienceDirectESM
Highlights
1. Currently, HCV 6a has replaced 1b as the most prevalent subtype in blood donors in Guangdong.
2. HCV 6a was the predominant subtype in males and older donors, while 1b predominated in females and younger donors.
3. HCV 6a may expand from Guangdong to other districts of China, and is worthy of attention

Development of stable, cold-adapted, temperature-sensitive/conditional lethal chimeric enterovirus A71 and coxsackievirus A16

Kaw Bing Chua, Qimei Ng, Tao Meng, Qiang Jia

2022, 37(5): 769 doi: 10.1016/j.virs.2022.08.001

Received: 17 August 2021 Accepted: 02 August 2022
Abstract [PDF 1623 KB] ScienceDirectESM
Highlights
1 A stable EV-A71 virus vector was created to generate chimeric enterovirus strains expressing capsid protein genes of EV-A71 subgenogroup C5 and CA16.
2 Phenotypic and genetic stability of the generated chimeric EV-A71 and CA16 were analyzed.
3 The amino acids at the cleavage site between VP1 and 2A is crucial for stability.

Screening for arboviruses in healthy blood donors: Experience from Karachi, Pakistan

Moiz Ahmed Khan, Kehkashan Imtiaz, Humaira Shafaq, Joveria Farooqi, Mohammad Hassan, Afia Zafar, Maureen T. Long, Kelli L. Barr, Erum Khan

2022, 37(5): 774 doi: 10.1016/j.virs.2022.07.008

Received: 15 December 2021 Accepted: 13 July 2022
Abstract [PDF 344 KB] ScienceDirectESM
Highlights:
1 Potential transfusion-related transmission of DENV, WNV and JEV was investigated in healthy blood donors from the blood bank of Aga Khan University during July to December 2018.
2 ELISA for DENV, WNV and JEV IgM antibodies and RT-PCR for viral RNA detection were performed.
3 Of the 360 blood donors screened, IgM antibodies for DENV and WNV were positive in 3.9% and JEV in 0.28% respectively while none of the blood donors tested positive for RT-PCR.
4 Majority of the seropositive donors were between 19 to 30 years of age and residents of urban areas, mainly from Karachi City.
5 DENV and WNV seropositivity were significantly associated with residence in Malir District of Karachi.
Perspective

Severe acute hepatitis in children with unknown aetiology, etiology analysis and the next action

Yuan Gao, Leijie Wang, Lin Wang, Fengmin Lu

2022, 37(5): 778 doi: 10.1016/j.virs.2022.07.004

Received: 27 May 2022 Accepted: 04 July 2022
Abstract [PDF 1482 KB] ScienceDirectESM
Highlights
1. MIS-C and severe acute hepatitis might share the common pathogenic mechanism;
2. SARS-CoV-2 persistence throughout multiorgan and tissues;
3. Relationship between COVID-19 vaccines and severe acute hepatitis worth investigating.