Nipah virus (NiV) and related viruses form a distinct henipavirus genus within the Paramyxoviridae family. NiV continues to spillover into the humans causing deadly outbreaks with increasing human-bat interaction. NiV encodes the large protein (L) and phosphoprotein (P) to form the viral RNA polymerase machinery. Their sequences show limited homologies to those of non-henipavirus paramyxoviruses. We report two cryo-electron microscopy (cryo-EM) structures of the Nipah virus (NiV) polymerase L-P complex, expressed and purified in either its full-length or truncated form. The structures resolve the RNA-dependent RNA polymerase (RdRp) and polyribonucleotidyl transferase (PRNTase) domains of the L protein, as well as a tetrameric P protein bundle bound to the L-RdRp domain. L-protein C-terminal regions are unresolved, indicating flexibility. Two PRNTase domain zinc-binding sites, conserved in most Mononegavirales, are confirmed essential for NiV polymerase activity. The structures further reveal anchoring of the P protein bundle and P protein X domain (XD) linkers on L, via an interaction pattern distinct among Paramyxoviridae. These interactions facilitate binding of a P protein XD linker in the nucleotide entry channel and distinct positioning of other XD linkers. We show that the disruption of the L-P interactions reduces NiV polymerase activity. The reported structures should facilitate rational antiviral-drug discovery and provide a guide for the functional study of NiV polymerase.
Nipah Virus/chemistry* ; Cryoelectron Microscopy ; Viral Proteins/genetics* ; RNA-Dependent RNA Polymerase/genetics* ; Phosphoproteins/genetics* ; Humans ; Models, Molecular ; Protein Binding

Nipah virus (NiV) is a zoonotic paramyxovirus that has recently emerged as a crucial public health issue. It can elicit severe encephalitis and respiratory diseases in animals and humans, leading to fatal outcomes, exhibiting a wide range of host species tropism, and directly transmitting from animals to humans or through an intermediate host. Human-to-human transmission associated with recurrent NiV outbreaks is a potential global health threat. Currently, the lack of effective therapeutics or licensed vaccines for NiV necessitates the primary utilization of supportive care. In this review, we summarize current knowledge of the various aspects of the NiV, including therapeutics, vaccines, and its biological characteristics, epidemiology, pathogenesis, and clinical features. The objective is to provide valuable information from scientific and clinical research and facilitate the formulation of strategies for preventing and controlling the NiV.
Animals ; Humans ; Disease Outbreaks/prevention & control* ; Henipavirus Infections/virology* ; Nipah Virus/pathogenicity* ; Viral Vaccines ; Zoonoses/virology*

A simple, fast, and visual method for detecting antibodies against peste des petits ruminants virus (PPRV) using colloidal gold strips was developed. In this study, the pET-32a-N was transformed into Escherichia coli Rosetta (DE3) for expression. Hybridoma cell lines were generated by fusing SP2/0 myeloma cells with splenocytes from immunized mice with the expressed and purified N protein of PPRV. The PPRV N protein was labeled with colloidal gold particles as the gold-labeled antigen. The N protein served as the gold standard antigen and as the test (T) line-coated antigen, while the monoclonal antibody served as the quality control (C) line-coated antibody to assemble the colloidal gold immunochromatographic test strips for detecting antibodies against the N protein of PPRV. Hybridoma cell line designated as 1F1 was able to stably secrete the monoclonal antibody against the N protein of PPRV. The titer of 1F1 monoclonal antibody in ascites was 1:128 000 determined by indirect enzyme-linked immunosorbent assays (ELISA), and the immunoglobulin subtype of the monoclonal antibody was IgG1, with kappa chain. The obtained monoclonal antibody was able to specifically recognize the N protein of PPRV, as shown by Western blotting and indirect immunofluorescent assay (IFA). The developed colloidal gold test strip method was able to detect PPRV antibodies specifically, and there was no difference between different batches of the test strips. Testing of a total of 122 clinical sera showed that the compliance rate of the test strip with ELISA test was 97.6%.The test strip assay developed in this study has good specificity, reproducibility, and sensitivity, and it can be used for the rapid detection of PPRV antibodies.
Animals ; Mice ; Peste-des-Petits-Ruminants/prevention & control* ; Antibodies, Monoclonal ; Reproducibility of Results ; Peste-des-petits-ruminants virus ; Antibodies, Viral ; Enzyme-Linked Immunosorbent Assay ; Goats

Adult ; Aged ; Antibodies, Viral/metabolism* ; China ; Female ; Humans ; Immunoglobulin G/metabolism* ; Male ; Measles/metabolism* ; Measles virus/physiology* ; Medical Staff ; Middle Aged ; Saliva/virology* ; Young Adult

The aim of this study was to develop a semi-quantitative immunochromatographic method for rapid detection of Newcastle disease virus (NDV) antibodies by expressing HN protein in rice endosperm bioreactor. The recombinant plasmid pUC57-HN was digested by MlyⅠ and XhoⅠ to retrieve the HN gene, while the intermediate vector pMP3 containing promoter, signal peptide and terminator was digested by NaeⅠ and XhoⅠ. The HN gene and the linearized pMP3 were purified and ligated to form a recombinant plasmid pMP3-HN1. Subsequently, pMP3-HN1 and plant vector pCAMBIA1300 were digested by EcoRⅠ and Hind Ⅲ, and the HN1 gene was cloned into pCAMBIA1300. The recombinant plasmid pCAMBIA1300-HN1 was introduced into Agrobacterium tumefaciens EHA105 by electrotransformation, and the pCAMBIA1300-HN1 was transferred into rice callus by agrobacterium-mediated method. After dark culture, callus screening, differentiation, rooting and transplanting, transgenic rice seeds were obtained 4 months later. PCR identified that the HN gene has been inserted into the rice genome. SDS-PAGE and Western blotting indicated that the HN protein was successfully expressed in the positive rice endosperm. The purity of the HN protein was more than 90% by SP cation exchange chromatography and gel filtration chromatography. According to the national standards for the diagnostic techniques of Newcastle disease HI test (HI≥4log₂, positive antibody reaction), a colloidal gold labeled purified HN protein was used to prepare a semi-quantitative test strip by double-antibody sandwich method for rapid detection of NDV antibody. The results showed that the test strip did not cross-react with positive sera against other viruses, and the sensitivity of the test strip reached 1:102 400 for standard positive sera of Newcastle disease. Testing of a total of 308 clinical sera showed that the compliance rate of the test strip with HI test was 97.08%, and the Kappa value was 0.942. In conclusion, high purity recombinant HN protein was obtained from rice endosperm, and a simple, rapid, highly sensitive and highly specific semi-quantitative immunochromatographic strip was developed. The test strip could be used for immune evaluation of the Newcastle disease vaccine.
Animals ; Antibodies, Viral ; Chickens ; HN Protein/metabolism* ; Newcastle Disease/prevention & control* ; Newcastle disease virus/metabolism* ; Oryza/genetics*

Background. Subacute sclerosing panencephalitis (SSPE) is a fatal neurodegenerative disease caused by prolonged persistent infection of the central nervous system with a measles virus mutant. Though various treatment modalities have been tried, there is no effective treatment to completely cure SSPE and new therapeutic strategies are needed.

Objective. This is a prospective uncontrolled observational open label trial to describe the short-term outcomes and safety of intraventricular ribavirin in combination with oral isoprinosine in Filipino SSPE patients.

Methods. Sixteen (16) unrelated SSPE patients between ages 3-26 years and in various clinical stages were included in this study. Demographic data were described. Intraventricular instillation of ribavirin (1-3 mg/kg/dose) through an Ommaya reservoir was given for a duration of 3-6 months in 13 patients. The duration of follow-up was 48 weeks. The clinical outcome was assessed before, during, and after treatment using the Neurological Disability Index (NDI), Brief Assessment Examination (BAE), and clinical staging using the Jabbour Classification. Adverse side effects from intraventricular ribavirin were enumerated.

Results. Six of 13 (46.15%) patients mostly in Stage III illness had clinical improvement showing decreasing NDI and BAE scores during treatment and the clinical improvement was maintained or improved further during the 48-week follow-up period. Clinical improvement manifested as improved mental alertness, decrease in spasticity and reduction of seizures. The clinical staging of those who improved remained stable during and after treatment was discontinued. Five (38.46%) patients in Stage II disease worsened and progressed to Stage III despite ribavirin therapy including 1 (7.6%) patient who died after the treatment phase due to pneumonia and brainstem failure. The clinical course of two (15.38%) patients remained unchanged. Minor adverse side effects of ribavirin included transient fever, rash, oral sores, seizure episodes, drowsiness, bladder retention and mild increase in transaminases. Ommaya reservoir infection was a serious adverse event in 5 (31.25%) patients.

Conclusion. There is still no definitive cure for SSPE. Although ribavirin may help alleviate some of the symptoms of SSPE and prolong life, it may not reverse or halt the progression of the disease. Long term follow-up of these patients and continuous use of intraventricular ribavirin will better clarify its role in modifying the fatal course of SSPE. The role of ribavirin in Stage I patients and a controlled clinical trial in Stage II SSPE needs further studies.

Human parainfluenza viruses (HPIVs) is one of the main causes of acute respiratory tract infections in children. HPIVs have been grouped into four serotypes (HPIV1~HPIV4) according to serological and genetic variation. Different serotypes of HPIVs have diverse clinical disease spectrum, epidemic characteristics and disease burden. Based on the nucleotide variation in structural protein genes, HPIVs can be further divided into distinct genotypes and subtypes with diverse temporal and spatial distribution features. The standard molecular typing methods are helpful to clarify the gene evolution and transmission patterns of HPIVs in the process of population transmission. However, the development of molecular epidemiology of HPIVs has been hindered by the lack of a standardized molecular typing method worldwide. Therefore, this study reviewed the viral characteristics, genome structure, existing genotyping methods and evolution of HPIVs, and screened the reference strains for molecular typing, so as to improve the understanding of gene characteristics and molecular typing of HPIVs, and provide an important scientific basis for the monitoring and research of molecular epidemiology of HPIVs in China.
Child ; Humans ; Molecular Typing ; Parainfluenza Virus 1, Human/genetics* ; Parainfluenza Virus 2, Human/genetics* ; Parainfluenza Virus 3, Human/genetics* ; Paramyxoviridae Infections/epidemiology* ; Respiratory Tract Infections/epidemiology*

The purpose was to discuss the infection status of human parainfluenza virus type 3 (HPIV-3) in children with acute respiratory tract infection(ARTI) in Qingdao, Shandong province, and to analyze the gene characteristics of HPIV-3 hemagglutinin-neuraminidase protein (HN). This study was a cross-sectional study. A total of 1 674 throat swab samples were collected randomly from children with ARTI, in the three hospitals (Qingdao Women and Children's Hospital, West Coast Branch of Affiliated Hospital of Qingdao University, Laoshan Branch of Affiliated Hospital of Qingdao University) from January 2018 to December 2019. Multiplex real-time fluorescence RT-PCR was performed to screen HPIV-3 positive specimens. For HPIV-3 positive specimens, nested PCR was used to amplify the full-length HN gene of HPIV-3. The HN gene was sequenced and compared with the representative strains of HPIV-3 in GenBank, and the phylogenetic tree was established. As results, this study collected 1 674 samples, in which there were 90 HPIV-3 positive samples showed and the detection rate was 5.37%. Among positive specimens, the number of samples from children under 6 years old was 88, accounting for 97.78%. HPIV-3 positive cases were mainly distributed in spring and summer. The full-length sequences of 44 HPIV-3 HN genes were obtained by nested PCR method. Sequence alignment and evolutionary analysis showed that the HPIV-3HN gene belonged to the C3a and C3b branches of C3 genotype, with 30 strains of subtype C3a and 14 strains of subtype C3b. The nucleotide and amino acid homology of the amplified 44 strains of the HPIV-3 HN gene in Qingdao were 97.0%-100.0% and 98.5%-100.0%, respectively. In conclusion, from 2018 to 2019, the C3a and C3b branches of HPIV-3 C3 genotype were circulating prevalent in Qingdao, Shandong province. HN gene variation rate was low, but showed certain regional characteristics in evolution.
Child ; Child, Preschool ; Cross-Sectional Studies ; Female ; Hemagglutinins ; Humans ; Neuraminidase ; Parainfluenza Virus 3, Human/genetics* ; Phylogeny ; Respiratory Tract Infections/epidemiology* ; Viral Proteins

Nipah virus disease (NVD) is a newly emerged zoonosis with a case fatality rate of 40%-75%. NVD is a severe threat to human health and the development of livestock farming. NVD has become one of the emerging infectious diseases with great concern globally during more than 20 years. Nipah virus (NiV) is a pathogen for NVD, the natural host of which is Fruit bats of the Pteropodidae family. The clinical spectrum of NiV infection is broad, including asymptomatic infection, acute respiratory infection, fatal encephalitis, and even death. Since NiV was first identified in Malaysia in 1999, it has been prevalent mainly in Southeast Asia and South Asia. NiV is primarily transmitted to humans through bat-pig-human, contaminated food. Currently, there are no specific therapeutic drugs and vaccines for NVD. Although there are no cases of NVD reported in China, which has close personnel and trade exchanges with major NVD-endemic countries, and NiV antibody has also been detected in relevant bats. There is a potential risk of importing NVD and domestic outbreaks in the future in this country. This paper provides a systematic review of the research progress in the prevention and control of NVD etiology, epidemiology, clinical manifestations and laboratory diagnosis to help relevant staff to understand NVD more comprehensively and systematically.
Animals ; Chiroptera ; Communicable Diseases, Emerging/prevention & control* ; Disease Outbreaks ; Henipavirus Infections/prevention & control* ; Nipah Virus ; Swine ; Zoonoses/prevention & control*

Objective: To determine IgG antibody levels of measles, rubella, mumps in healthy population in Shanghai from 2010 to 2020 and analyze the trend of antibody changes in different age groups. Methods: 10 828 healthy people without measles, rubella and mumps in Shanghai were included in the study from 2010 to 2020. Serum samples were collected from 12 age groups, and the serum IgG antibody of measles, rubella and mumps were detected by ELISA. The difference of antibody positive rates and antibody levels were analyzed. Results: The median age M (Q₁, Q₃) of 10 828 objects were 8 years old (9 months old, 20 years old). Males accounted for 48.34% (5 234/10 828) and females accounted for 50.92% (5 514/10 828). Unknown gender information accounted for 0.74% (80/10 828), and 27.03% (2 927/10 828) of participants had unknown MMR immunization history. The total positive rates of measles, rubella and mumps IgG antibody were 76.78%, 64.46% and 64.29% and their GMCs were 541.45 mIU/ml, 31.76 IU/ml and 133.73 U/ml respectively. There were significant differences in serum IgG antibody GMC of measles, rubella and mumps in each year (F_measles=180.74, P<0.001; F_rubella=189.95, P<0.001; F_mumps=122.40, P<0.001). The positive rate of measles antibody was higher than that of rubella and mumps, and the difference was statistically significant (χ²=518.09, P<0.001). Conclusion: The level of measles IgG antibody in healthy people in Shanghai is higher, while the level of rubella and mumps IgG antibody is slightly lower.
Adult ; Antibodies, Viral ; Child ; China/epidemiology* ; Female ; Humans ; Immunoglobulin G ; Infant ; Male ; Measles/prevention & control* ; Measles-Mumps-Rubella Vaccine ; Mumps/prevention & control* ; Mumps virus ; Rubella/prevention & control* ; Young Adult