Genomic and phylodynamic analysis of sapoviruses isolated in Henan Province, China.

In this study, we determined the near-complete and partial genome sequences of ten SaV isolates. Phylogenetic analysis based on full-length VP1 and RdRp nucleotide sequences indicated that nine isolates were of GI.1 and one was GII.3. Evolutionary dynamics analysis indicated that GI.1 and GII.3 SaVs evolved at different rates, the latter evolving more rapidly. Cluster analysis indicated that distantly related GI.1 SaVs were more similar in their amino acid compositions than were GII.3 SaVs. The data provided in this study may facilitate studies on SaV genomic diversity and epidemiological patterns in China and worldwide.

Phylogenetic and biological characterizations of a GI.3 norovirus.

Noroviruses (NoVs) are a major cause of acute non-bacterial gastroenteritis worldwide. In this study, we report the isolation, near-complete genome sequencing, and expression and biological characterization of the major capsid protein (VP1) of a GI.3 NoV isolated from a child presenting acute gastroenteritis. The genome of the GI.3 NoV is 7746 bp in length, not including the poly-adenylation tail. Phylogenetic analysis based on the complete VP1 nucleotide sequences indicates that GI.3 NoVs could be divided into four clusters, with 4.6%, 5.3%, 6.6%, 1.9% intracluster variations in nucleotide and 4.8%, 3.8%, 6.1%, 1.7% intracluster variations in amino acid sequences, respectively. A Bayesian evolutionary analysis showed that GI.3 NoVs evolved at 2.44 × 10-3, 2.78 × 10-3, and 3.04 × 10-3 nucleotide substitutions/site/year using a strict clock model, an uncorrelated log-normal model (UCLN), and an uncorrelated exponential derivation model (UCED), respectively. VP1 protein expression using a recombinant baculovirus expression system leads to the successful assembly of virus-like particles (VLPs). In vitro VLP-Histo-blood group antigen (HBGA) binding assay indicates that GI.3 NoV VLPs strongly bind to blood type A salivary HBGAs, moderately bind to blood type O salivary HBGAs, and weakly bind or do not bind to blood type B and AB salivary HBGAs. In vitro VLP-HBGA binding blockade assay indicated that the binding of GI.3 NoV VLPs to blood type A salivary HBGAs could only be blocked by anti-GI.3 NoV VLPs serum but not non-GI.3 NoV genotype-specific hyperimmune sera (GI.2, GI.7, GII.4, GII.6, GII.7, and GII.17). The detailed characterization of GI.3 NoV in this study provides evidence that GI.3 NoV undergoes rapid evolution and exhibits no cross-blocking effects, suggesting that GI.3 NoV may potentially be utilized in the development of multivalent NoV vaccines.

Clinical course and treatment efficacy of COVID-19 near Hubei Province, China: A multicentre, retrospective study.

Currently, COVID-19 has been reported in nearly all countries globally. To date, little is known about the viral shedding duration, clinical course and treatment efficacy of COVID-19 near Hubei Province, China. This multicentre, retrospective study was performed in 12 hospitals in Henan and Shaanxi Provinces from 20 January to 8 February 2020. Clinical outcomes were followed up until 26 March 2020. The viral shedding duration, full clinical course and treatment efficacy were analysed in different subgroups of patients. A total of 149 COVID-19 patients were enrolled. The median age was 42 years, and 61.1% (91) were males. Of them, 133 (89.3%) had fever, 131 of 144 (91%) had pneumonia, 27 (18.1%) required intensive care unit (ICU) management, 3 (2%) were pregnant, and 3 (2%) died. Two premature newborns were negative for SARS-CoV-2. In total, the median SARS-CoV-2 shedding period and clinical course were 12 (IQR: 9-17; mean: 13.4, 95% CI: 12.5, 14.2) and 20 (IQR: 16-24; mean: 21.2, 95% CI: 20.1, 22.3) days, respectively, and ICU patients had longer median viral shedding periods (21 [17-24] versus 11 [9-15]) and clinical courses (30 [22-33] vs. 19 [15.8-22]) than non-ICU patients (both p < .0001). SARS-CoV-2 clearances occurred at least 2 days before fatality in 3 non-survivors. Current treatment with any anti-viral agent or combination did not present the benefit of shortening viral shedding period and clinical course (all p > .05) in real-life settings. In conclusion, the viral shedding duration and clinical course in Henan and Shaanxi Provinces were shorter than those in Hubei Province, and current anti-viral therapies were ineffective for shortening viral shedding duration and clinical course in real-world settings. These findings expand our knowledge of the SARS-CoV-2 infection and may be helpful for management of the epidemic outbreak of COVID-19 worldwide. Further studies concerning effective anti-viral agents and vaccines are urgently needed.

Effect of Convalescent Plasma Therapy on Viral Shedding and Survival in Patients With Coronavirus Disease 2019.

Currently, coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been reported in almost all countries globally. No effective therapy has been documented for COVID-19, and the role of convalescent plasma therapy is unknown. In the current study, 6 patients with COVID-19 and respiratory failure received convalescent plasma a median of 21.5 days after viral shedding was first detected, all tested negative for SARS-CoV-2 RNA within 3 days after infusion, and 5 eventually died. In conclusion, convalescent plasma treatment can end SARS-CoV-2 shedding but cannot reduce the mortality rate in critically ill patients with end-stage COVID-19, and treatment should be initiated earlier.

Characterization of HIV-1 subtypes and drug resistance mutations in Henan Province, China (2017-2019).

Human immunodeficiency virus type 1 (HIV-1) infection remains a severe public health problem worldwide. In this study, we investigated the distribution of HIV-1 subtypes and the prevalence of drug resistance mutations (DRMs) among patients with HIV-1 infection in Henan Province, China. HIV-1 strains in blood samples taken from inpatients and outpatients visiting the Sixth People's Hospital of Zhengzhou from August 2017 to July 2019 with a viral load (VL) greater than 1000 copies/ml were subjected to subtype and DRMs analysis. Out of a total of 769 samples, subtype and DRM data were obtained from 657 (85.43%) samples. Phylogenetic analysis based on partial pol gene sequences indicated that the most commonly found genotype was subtype B (45.51%, 299/657), followed by CRF01_AE (28.61%, 188/657), CRF07_BC (15.68%, 103/657), CRF08_BC (0.76%, 5/657), C (0.61%, 4/657), A (0.30%, 2/657), and others (8.52%, 56/657). Circulating recombinant forms (CRFs) were most commonly found in patients who were naïve to antiretroviral treatment (ART) (68.67%, 160/233). The percentage of patients with one or more major drug-resistance mutations was 50.99% (335/657), and it was 6.44% (15/233) in ART-naive patients that were primarily infected with subtype B (17.74%). Resistance mutations were most common at codons 65, 103, 106, 184, and 190 of the reverse transcriptase gene and codon 46 of the protease gene. Our study provides detailed information about the distribution of HIV-1 subtypes and the incidence of drug resistance mutations of different subtypes in ART-experienced and naïve patients. This can guide policymakers in making decisions about treatment strategies against HIV-1.

Prevalence and genotype distribution of human papillomavirus in Zhengzhou, China, in 2016.

In this study, the prevalence and genotype distribution of human papillomavirus (HPV) in 49,793 women aged 25-64 years were determined by fluorescent real-time polymerase chain reaction (PCR) assay. HPV was detected in 6,020 women, giving a prevalence of 12.09% (6020/49,793). Single and multiple infections accounted for 71.81% (4323/6020) and 28.19% (1697/6020) of total infections, respectively. The most commonly found genotypes were HPV52 (19.90%, 1198/6020) and HPV16 (19.17%, 1154/6020), followed by HPV58 (13.11%, 789/6020), HPV81 (10.10%, 608/6020) and HPV56 (9.00%, 542/6020). The prevalence of HPV increased with age and was highest in the 54- to 64-year-old age group. The genotypes covered by the nonavalent HPV vaccine accounted for 39.32% (2367/6020) and 22.81% (1373/6020) of the total monoinfections and polyinfections, respectively. This study indicates a high HPV infection rate in women in the city of Zhengzhou and a large percentage of women are infected with single or multiple high-risk HPV genotypes that cannot be prevented using the current nonavalent HPV vaccine. Vaccines incorporating more HPV genotypes and extended age coverage for the current nonavalent vaccine might be necessary to better prevent HPV-related cervical cancer.

Linear epitope binding antibodies against GII.3 Norovirus exhibit no histo-blood group antigens (HBGAs) blocking effects.

Noroviruses are leading cause of acute gastroenteritis worldwide. In our previous study, we established an in vitro histo-blood group antigens (HBGAs) binding blockade assay against GII.3 Norovirus virus like particles (VLPs) with trypsin digestion. In this study, we characterized the blocking antibody binding site and epitope type (linear or conformational) by using hyperimmune sera produced against different antigens. VP1 from Jingzhou402 (GII.3, JZ402) strain was expressed by using pGEX-6p-1 expression vector and the insoluble proteins were purified for immunization in rabbit. Previously characterized chimeric VP1-assembled VLPs (GII.4-VP1/GII.3-P2) were used to immunize guinea pig. Peptides reactive with hyperimmune serum against VLPs derived from the VP1 of JZ402 strain were conjugated with BSA and used to immunize rabbits. Hyperimmune sera against above antigens and JZ402 and JZ403 strain-derived VLPs were used to compare their HBGAs blocking effects. Rabbit anti-GST-VP1 and BSA-peptide conjugated hyperimmune sera demonstrated no blocking effects against the binding of GII.3 and GII.4 NoV VLPs to salivary HBGAs. Guinea pig anti-GII.4-VP1/GII.3-P2 hyperimmune serum blocked the binding of trypsin cleaved GII.3 VLPs to salivary HBGAs with no or very weak blocking effects against the binding of GII.4 VLPs to salivary HBGAs. Our data indicated that HBGAs blocking antibodies primarily bound the P2 domain of GII.3 NoV VP1 and their binding epitopes were most probably conformation-dependent.

Chimeric GII.3/GII.6 norovirus capsid (VP1) proteins: characterization by electron microscopy, trypsin sensitivity and binding to histo-blood group antigens.

GII.3 and GII.6 noroviruses (NoVs) are similar in several aspects, including the presence of a short sequence insertion in the P2 domain of the major capsid protein (VP1) and trypsin susceptibility of VP1-containing virus-like particles (VLPs). In this study, we generated two constructs with the S or P domains of VP1 from GII.3 and GII.6 NoV strains exchanged (GII.3S/GII.6P and GII.6S/GII.3P), and the resultant chimeric capsid proteins were expressed from recombinant baculoviruses. The assembly of VLPs was confirmed by electron microscopy, and the susceptibility of assembled VLPs to trypsin digestion was analyzed by SDS-PAGE. Salivary histo-blood group antigen (HBGA) binding and binding blockade assays were performed to determine the binding characteristics of chimeric VP1-containing VLPs with and without trypsin digestion. Our results indicated that both expressed GII.3S/GII.6P and GII.6S/GII.3P chimeric proteins successfully assembled into VLPs. Trypsin digestion of VLPs assembled from both chimeric proteins led to the generation of two fragments with molecular sizes similar to those of wild-type VP1-containing VLPs. An in vitro salivary HBGA binding assay demonstrated that VLPs assembled from both chimeric proteins exhibited enhanced binding after trypsin cleavage. An HBGA binding blockade assay indicated that the binding of GII.3S/GII.6P and GII.6S/GII.3P VLPs against salivary HBGAs could only be blocked by GII.3 and GII.6 NoV VLP-specific hyperimmune sera, respectively. For GII.6 and GII.3S/GII.6P VLPs, a difference in binding enhancement after trypsin cleavage was observed. Our results demonstrate that the S domains of GII.3 and GII.6 NoV VP1 are interchangeable and that the S domain affects the binding of the P domain to HBGAs.