ICTV Virus Taxonomy Profile: Paramyxoviridae

Simple and Rapid Colorimetric Detection of Canine Parainfluenza Virus 5 (Orthorubulavirus mammalis) Using a Reverse-Transcription Loop-Mediated Isothermal Amplification Assay

Despite its many advantages, a reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay has yet to be developed for canine parainfluenza virus 5 (CPIV5). In this study, a visual RT-LAMP (vRT-LAMP) assay was developed for the rapid detection of CPIV5 in clinical samples. At a constant reaction temperature of 62 °C, the assay was completed within 40 min, and the results could be directly detected with the naked eye using a hydroxynaphthol blue (HNB) metal indicator without any additional detection apparatuses. The assay specifically amplified CPIV5 RNA with a limit of detection of 10 RNA copies/reaction, which was 10-fold more sensitive than the previously reported conventional reverse-transcription polymerase chain reaction (cRT-PCR) assay and was comparable to the previously reported real-time RT-PCR (qRT-PCR) assay. In a clinical evaluation using 267 nasopharyngeal swab samples collected from hospitalized dogs with respiratory symptoms, the CPIV5 detection rate using the vRT-LAMP assay was 5.24% (14/267), which was higher than that of the cRT-PCR assay (4.49%, 12/267) and consistent with that of the qRT-PCR assay, demonstrating 100% concordance with a kappa coefficient value (95% confidence interval) of 1 (1.00-1.00). The discrepancies in the results of the assays were confirmed to be attributed to the low sensitivity of the cRT-PCR assay. Owing to the advantages of a high specificity, rapidity, and simplicity, the developed vRT-LAMP assay using an HNB metal indicator will be a valuable diagnostic tool for the detection of CPIV5 in canine clinical samples, even in resource-limited laboratories.

Structures of Langya Virus Fusion Protein Ectodomain in Pre- and Postfusion Conformation

Langya virus (LayV) is a paramyxovirus in the Henipavirus genus, closely related to the deadly Nipah (NiV) and Hendra (HeV) viruses, that was identified in August 2022 through disease surveillance following animal exposure in eastern China. Paramyxoviruses present two glycoproteins on their surface, known as attachment and fusion proteins, that mediate entry into cells and constitute the primary antigenic targets for immune response. Here, we determine cryo-electron microscopy (cryo-EM) structures of the uncleaved LayV fusion protein (F) ectodomain in pre- and postfusion conformations. The LayV-F protein exhibits pre- and postfusion architectures that, despite being highly conserved across paramyxoviruses, show differences in their surface properties, in particular at the apex of the prefusion trimer, that may contribute to antigenic variability. While dramatic conformational changes were visualized between the pre- and postfusion forms of the LayV-F protein, several domains remained invariant, held together by highly conserved disulfides. The LayV-F fusion peptide (FP) is buried within a highly conserved, hydrophobic interprotomer pocket in the prefusion state and is notably less flexible than the rest of the protein, highlighting its "spring-loaded" state and suggesting that the mechanism of pre-to-post transition must involve perturbations to the pocket and release of the fusion peptide. Together, these results offer a structural basis for how the Langya virus fusion protein compares to its Henipavirus relatives and propose a mechanism for the initial step of pre- to postfusion conversion that may apply more broadly to paramyxoviruses. IMPORTANCE The Henipavirus genus is quickly expanding into new animal hosts and geographic locations. This study compares the structure and antigenicity of the Langya virus fusion protein to other henipaviruses, which have important vaccine and therapeutic development implications. Furthermore, the study proposes a new mechanism to explain the early steps of the fusion initiation process that can be more broadly applied to the Paramyxoviridae family.

PCR-Based Detection and Genetic Characterization of Parainfluenza Virus 5 Detected in Pigs in Korea from 2016 to 2018

This study applied a molecular-based method to detect parainfluenza virus 5 (PIV5) collected from 2016 to 2018 in nine provinces of Republic of Korea. We demonstrated that PIV5 was detectable in both serum and pooled organs at an average positive rate of 1.78% (99/5566). Among these, the complete genome sequence of 15,246 nucleotides was obtained for 12 field strains. Three out of the 12 strains had the lowest genetic identity (96.20-96.68%) among the 21 porcine PIV5 genomes collected in Germany, China, India, and Republic of Korea from 1998 to 2017. By analyzing a large collection of complete genome sequences of the structural protein-coding F and HN genes, this study proposed a classification of PIV5 into two lineages, 1 and 2, and identified that group 2.2.2 within sub-lineage 2.2 was substantially divergent. The evolution of two structural protein-coding genes was largely under purifying selection. A few codons (6/9 for the F gene, 7/8 for the HN gene) had elevated dN/dS values, which were loaded on internal branches and were predicted to be related to beneficial trait(s) of the virus.

Are Measles-Mumps-Rubella (MMR) Antibodies Friends or Foes for Covid-19 Disease?

Many factors have been implicated in the pathogenesis and severity of COVID-19 pandemic. A wide variation in the susceptibility for SARS-CoV-2 infection among different population, gender and age has been observed. Multiple studies investigated the relationship between the antibody's titre of previously vaccinated individuals and the susceptibility of coronavirus infection, to find a rapid effective therapy for this pandemic. This study focused on the association between measles-mumps-rubella (MMR) antibodies titre and the severity of COVID-19 infection. We aimed to investigate the correlation between the antibody's titre of MMR and the SARS-CoV-2 infection susceptibility and disease severity, in a cohort of COVID-19 Egyptian patients, compared to a control group. MMR antibody titre was measured using enzyme Linked Immune Sorbent Assay; (ELISA) for 136 COVID-19 patients and 44 healthy individuals, as control group. There were high levels of measles and mumps antibodies titer in the deteriorating cases, which could not protect from SARS-CoV-2 infection. However, the rubella antibodies might protect from SARS-CoV-2 infection, but once the infection occurs, it may aggravate the risk of case deterioration. MMR antibodies could be used as a guideline for COVID-19 symptom-severity and, in turn, may be considered as an economic prognostic marker used for early protection from multiple autoimmune organ failure.

An Outbreak of Newcastle Disease Virus in the Moscow Region in the Summer of 2022

In August 2022 on a backyard farm in the Moscow region of Russia, mortality was observed among chickens, and all 45 birds of a particular farm died or were slaughtered after the onset of symptoms within a few days. Paramyxovirus was isolated from the diseased birds. Based on the nucleotide sequences of the F and NP gene fragments, it was determined that the virus belonged to subgenotype VII.1 AAvV-1 class II. The cleavage site of the F gene ₁₀₉SGGRRQKRFIG₁₁₉ and T in 546 and 555 position of the NP gene were typical for the velogenic type. The genetically closest NDV isolates were found in Iran. The mean time of death of 10-day-old chicken embryos upon infection with the minimal infectious dose was 52 h, which is typical for the velogenic pathotype. The virus caused 100% death of six-week-old chickens during oral infection as well as 100% mortality of all contact chickens, including those located in remote cages, which proves the ability of the virus to spread not only by the fecal-oral route but also by the aerosol route. That demonstrates a high level of pathogenicity and contagiousness of the isolated strain for chicken. However, mice intranasally infected with high doses of the virus did not die.

Biomolecular Analysis of Canine Distemper Virus Strains in Two Domestic Ferrets (Mustela putorius furo)

Canine distemper is a contagious and severe systemic viral disease that affects domestic and wild carnivores worldwide. In this study, two adult female ferrets (Mustela putorius furo) were evaluated for cutaneous lesions. Scab, fur, and swab samples from the external auditory canal, cutaneous lesions, and scrapings were analyzed. Canine distemper virus (CDV)-positive samples underwent RT-PCR/RFLP with the restriction enzyme PsiI, and the hemagglutinin gene sequence was obtained. According to the restriction enzyme and sequence analyses, the viral strains were typed as CDV field strains that are included within the Europe lineage and distinct from those including vaccinal CDV strains. The sequence analysis showed the highest nucleotide identity rates in older Europe lineage CDV strains collected from dogs and a fox in Europe. This study is the first to report on CDV infection in ferrets in southern Italy and contributes to the current knowledge about natural CDV infection in this species. In conclusion, vaccination remains crucial for preventing the disease and counteracting cross-species infection. Molecular biology techniques can enable the monitoring of susceptible wild animals by ensuring the active surveillance of CDV spread.

A Booster with a Genotype-Matched Inactivated Newcastle Disease Virus (NDV) Vaccine Candidate Provides Better Protection against a Virulent Genotype XIII.2 Virus

Newcastle disease (ND) is endemic in Bangladesh. Locally produced or imported live Newcastle disease virus (NDV) vaccines based on lentogenic virus strains, locally produced live vaccines of the mesogenic Mukteswar strain, as well as imported inactivated vaccines of lentogenic strains, are being used in Bangladesh under different vaccination regimens. Despite these vaccinations, frequent outbreaks of ND are being reported in Bangladesh. Here we compared the efficacy of booster immunization with three different vaccines in chickens that had been primed with two doses of live LaSota vaccine. A total of 30 birds (Group A) were primed with two doses of live LaSota virus (genotype II) vaccine at days 7 and 28, while 20 birds (Group B) remained unvaccinated. At day 60, birds of Group A were divided into three sub-groups, which received booster immunizations with three different vaccines; A1: live LaSota vaccine, A2: inactivated LaSota vaccine, and A3: inactivated genotype XIII.2 vaccine (BD-C161/2010 strain from Bangladesh). Two weeks after booster vaccination (at day 74), all vaccinated birds (A1-A3) and half of the unvaccinated birds (B1) were challenged with a genotype XIII.2 virulent NDV (BD-C161/2010). A moderate antibody response was observed after the primary vaccination, which substantially increased after the booster vaccination in all groups. The mean HI titers induced by the inactivated LaSota vaccine (8.0 log₂/5.0 log₂ with LaSota/BD-C161/2010 HI antigen) and the inactivated BD-C161/2010 vaccine (6.7 log₂/6.2 log₂ with LaSota/BD-C161/2010 HI antigen) were significantly higher than those induced by the LaSota live booster vaccine (3.6 log₂/2.6 log₂ with LaSota/BD-C161/2010 HI antigen). Despite the differences in the antibody titers, all chickens (A1-A3) survived the virulent NDV challenge, while all the unvaccinated challenged birds died. Among the vaccinated groups, however, 50% of the chickens in Group A1 (live LaSota booster immunization) shed virus at 5- and 7-days post challenge (dpc), while 20% and 10% of the chickens in Group A2 (inactivated LaSota booster immunization) shed virus at 3 and 5 dpc, respectively, and only one chicken (10%) in Group A3 shed virus at 5 dpc. In conclusion, the genotype-matched inactivated NDV booster vaccine offers complete clinical protection and a significant reduction in virus shedding.

The genetic and biological characterization of the first avian paramyxovirus serotype 14 isolated from chicken in China

In October 2020, an avian paramyxovirus serotype 14 (APMV-14)-designated chicken/Fujian/2160/2020 (FJ2160) was isolated from tracheal and cloacal swab sample of chicken collected from live bird market in Fujian province in China during the active surveillance program. The complete genome of FJ2160 comprised 15,444 nucleotides (nt) complying with the paramyxovirus "rule of six" and encoded six non-overlapping structural proteins in the order of 3'-NP-P-M-F-HN-L-'5. The complete genome sequence analysis showed that FJ2160 had the highest identity (90.0%) with the APMV-14 isolated from Japan, while the nucleotide sequence identities of FJ2160 and other APMVs ranged from 42.4 to 51.1%. The F protein cleavage site was TREGR↓L, which resembled a lentogenic strain of APMV-1. Phylogenetic analysis revealed that the FJ2160 closest relative was APMV-14. The intracerebral pathogenicity index (ICPI) tests indicated that the virus was lentogenic. This is the first report of APMV-14 in China. These results provide evidence that APMV-14 could infect chickens and reveal the genetic characteristics and biological properties of the virus, which can help to better understand this new emerging APMV-14.

Emergence of biased hypermutation in a heterologous additional transcription unit in recombinant lentogenic Newcastle disease virus

Recombinant Newcastle disease virus (rNDV) strains engineered to express foreign genes from an additional transcription unit (ATU) are considered as candidate live-attenuated vector vaccines for human and veterinary use. Early during the COVID-19 pandemic we and others generated COVID-19 vaccine candidates based on rNDV expressing a partial or complete SARS-CoV-2 spike (S) protein. In our studies, a number of the rNDV constructs did not show high S expression levels in cell culture or seroconversion in immunized hamsters. Sanger sequencing showed the presence of frequent A-to-G transitions characteristic of adenosine deaminase acting on RNA (ADAR). Subsequent whole genome rNDV sequencing revealed that this biased hypermutation was exclusively localized in the ATU expressing the spike gene, and was related to deamination of adenosines in the negative strand viral genome RNA. The biased hypermutation was found both after virus rescue in chicken cell line DF-1 followed by passaging in embryonated chicken eggs, and after direct virus rescue and subsequent passaging in Vero E6 cells. Levels of biased hypermutation were higher in constructs containing codon-optimized as compared to native S gene sequences, suggesting potential association with increased GC content. These data show that deep sequencing of candidate recombinant vector vaccine constructs in different phases of development is of crucial importance in the development of NDV-based vaccines.

Discovery and characterization of novel paramyxoviruses from bat samples in China

Many paramyxoviruses are responsible for a variety of mild to severe human and animal diseases. Based on the novel discoveries over the past several decades, the family Paramyxoviridae infecting various hosts across the world includes 4 subfamilies, 17 classified genera and 78 species now. However, no systematic surveys of bat paramyxoviruses are available from the Chinese mainland. In this study, 13,064 samples from 54 bat species were collected and a comprehensive paramyxovirus survey was conducted. We obtained 94 new genome sequences distributed across paramyxoviruses from 22 bat species in seven provinces. Bayesian phylodynamic and phylogenetic analyses showed that there were four different lineages in the Jeilongvirus genus. Based on available data, results of host and region switches showed that the bat colony was partial to interior, whereas the rodent colony was exported, and the felines and hedgehogs were most likely the intermediate hosts from Scotophilus spp. rather than rodents. Based on the evolutionary trend, genus Jeilongvirus may have originated from Mus spp. in Australia, then transmitted to bats and rodents in Africa, Asia and Europe, and finally to bats and rodents in America.

Detection of Selected Canine Viruses in Nigerian Free-Ranging Dogs Traded for Meat Consumption

Animal trade favors the spreading of emerging and re-emerging pathogens. Concerns have been previously expressed regarding the risks of dog trade in spreading zoonotic pathogens in Nigeria. However, the role of these dogs in disseminating highly pathogenic canine viruses has not yet been explored. The present study aimed to identify selected canine viruses in dogs traded for meat consumption in Nigeria. A total of 100 blood samples were screened for carnivore protoparvovirus-1 (CPPV-1), canine adenovirus 1/2 (CAdV-1/2), canine circovirus (CaCV), and canine distemper virus (CDV) by using real-time PCR and conventional PCR and/or sequencing. CPPV-1 DNA was identified in 83% of canine samples while CaCV DNA and CDV RNA were detected in 14% and 17% of the dog samples, respectively. None of the dogs tested positive for CAdV-1/2. The CaCVs identified in this study clustered along with other European, Asian, and American strains. Moreover, CDV strains identified in Nigeria clustered in a separate lineage with the closest genetic relatedness to the Europe-South America-1 clade. Further surveys prior to and after arrival of dogs at the slaughtering points are required to clarify the real virus burden in these animals.

Kinetic analysis of paramyxovirus-sialoglycan receptor interactions reveals virion motility

Many viruses initiate infection by binding to sialoglycan receptors at the cell surface. Binding to such receptors comes at a cost, however, as the sheer abundance of sialoglycans e.g. in mucus, may immobilize virions to non-functional decoy receptors. As a solution, sialoglycan-binding as well as sialoglycan-cleavage activities are often present in these viruses, which for paramyxoviruses are combined in the hemagglutinin-neuraminidase (HN) protein. The dynamic interactions of sialoglycan-binding paramyxoviruses with their receptors are thought to be key determinants of species tropism, replication and pathogenesis. Here we used biolayer interferometry to perform kinetic analyses of receptor interactions of animal and human paramyxoviruses (Newcastle disease virus, Sendai virus, and human parainfluenza virus 3). We show that these viruses display strikingly different receptor interaction dynamics, which correlated with their receptor-binding and -cleavage activities and the presence of a second sialic acid binding site. Virion binding was followed by sialidase-driven release, during which virions cleaved sialoglycans until a virus-specific density was reached, which was largely independent of virion concentration. Sialidase-driven virion release was furthermore shown to be a cooperative process and to be affected by pH. We propose that paramyxoviruses display sialidase-driven virion motility on a receptor-coated surface, until a threshold receptor density is reached at which virions start to dissociate. Similar motility has previously been observed for influenza viruses and is likely to also apply to sialoglycan-interacting embecoviruses. Analysis of the balance between receptor-binding and -cleavage increases our understanding of host species tropism determinants and zoonotic potential of viruses.

Epidemiology of newcastle disease in village chicken in melokoza district, gofa zone, southwest Ethiopia

Poultry production contributes significantly to the livelihoods of Ethiopian farmers and the national economy, although it is hampered by different factors, including infectious diseases. A cross-sectional study was conducted from December 2019 to May 2020 in Melokoza District, Gofa Zone, Ethiopia. The objectives of the study were to estimate the seroprevalence of Newcastle disease in unvaccinated chickens and to identify the risk factors associated with the disease. A systematic random sampling technique was employed to select chickens from individual chicken owners. A total of 405 blood samples were collected and submitted to the national veterinary institute in Bishoftu, Ethiopia. Hemaglutination inhibition test was performed to detect antibodies from the collected chickens' serum. Both univariable and multivariable logistic regression analyses were performed by using the STATA statistical software package. The test result showed that the overall seroprevalence was 68.8% (95% CI: 64%, 73%). The highest seroprevalence of 86% (58/67) was recorded in Gazar kebele (lowland), whereas the lowest seroprevalence of 45% (32/71) was recorded in Maizelo (highland). Sex, age, altitude and management practice risk factors showed significant associations (p < 0.05) with the disease prevalence. In conclusion, this study emphasized the prevailing higher prevalence of Newcastle disease in free-scavenging chickens. Regular vaccination for Newcastle disease is therefore recommended. Further studies are warranted to better understand the circulating strain and its economic effect on backyard poultry production in the study area.

Genomic Characterization of a Relative of Mumps Virus in Lesser Dawn Bats of Southeast Asia

The importance of genomic surveillance on emerging diseases continues to be highlighted with the ongoing SARS-CoV-2 pandemic. Here, we present an analysis of a new bat-borne mumps virus (MuV) in a captive colony of lesser dawn bats (Eonycteris spelaea). This report describes an investigation of MuV-specific data originally collected as part of a longitudinal virome study of apparently healthy, captive lesser dawn bats in Southeast Asia (BioProject ID PRJNA561193) which was the first report of a MuV-like virus, named dawn bat paramyxovirus (DbPV), in bats outside of Africa. More in-depth analysis of these original RNA sequences in the current report reveals that the new DbPV genome shares only 86% amino acid identity with the RNA-dependent RNA polymerase of its closest relative, the African bat-borne mumps virus (AbMuV). While there is no obvious immediate cause for concern, it is important to continue investigating and monitoring bat-borne MuVs to determine the risk of human infection.

Game Birds Can Act as Intermediaries of Virulent Genotype VII Avian Orthoavulavirus-1 between Wild Birds and Domestic Poultry

Newcastle Disease (ND), caused by virulent forms of Avian orthoavulavirus serotype-1 (AOAV-1) is an economically important avian disease worldwide. The past two incursions of ND into the United Kingdom occurred in game bird populations during 2005 and 2006. The nature of the game bird semi-feral rearing system, which can bring these birds into close contact with both wild birds and commercial or backyard poultry, has been hypothesized to act as a bridge between these two environments. As such, the risk that AOAV-1-infected game birds may pose to the UK poultry industry was investigated. Pheasants, partridges and chickens were experimentally infected with the virulent strain APMV-1/Chicken/Bulgaria/112/13, a genotype VII.2 virus associated with ND outbreaks in Eastern Europe. The study demonstrated that both chickens and pheasants are susceptible to infection with APMV-1/Chicken/Bulgaria/112/13, which results in high mortality and onward transmission. Partridges by contrast are susceptible to infection, but mortality was reduced, as was onward transmission. However, the data indicated that both pheasants and partridges may serve as intermediate hosts of AOAV-1 and may bridge the wild bird-domestic poultry interface enabling transmission into an economically damaging environment where morbidity and mortality may be high.

Development and Evaluation of a Blocking Lateral Flow Assay Strip for Detection of Newcastle Disease Virus Antibodies

Newcastle disease (ND) is an acute septicemic infectious disease caused by Newcastle disease virus (NDV). Considering that vaccination is currently the main modality for the prevention of ND, it is essential to assess the effectiveness of clinical immunization. In this study, we have developed a blocking lateral flow assay (bLFA) strip for the rapid detection of NDV antibodies using the monoclonal antibody 9C1 against haemagglutinin-neuraminidase (HN), which allows for the determination of an NDV-specific antibody titer within 10 min at room temperature. In addition, the bLFA strip has no cross-reactivity with the positive serum of other avian pathogens including avian influenza subtypes H5, H7, and H9, MD, IBD, IB, EDS, and avian adenovirus. The ability of the bLFA strip for detecting a neutralizing antibody was also estimated. The results showed that the chicken NDV hyperimmunized serum had a complete blocking (100%) titer of 11 log 2, and half-blocking titer of 13 log 2, which are 4 times less than and the same as that of the HI test (13 log 2), and 8 and 2 times less than that of the VN test (14 log 2), respectively. A total of 510 clinical samples were tested for NDV antibodies. The coincidence rate between the results of the bLFA strip and HI test was 97.65%. Therefore, it is an ideal alternative method for assessing the clinical immunity of ND vaccines in the field in real-time.

An Improved Duplex Real-Time Quantitative RT-PCR Assay with a Canine Endogenous Internal Positive Control for More Sensitive and Reliable Detection of Canine Parainfluenza Virus 5

A duplex real-time quantitative reverse transcription-polymerase chain reaction (dqRT-PCR) assay was successfully developed to simultaneously detect canine parainfluenza virus 5 (CPIV5) and a canine endogenous internal positive control (EIPC) in canine clinical samples. Two sets of primers and probes for the CPIV5 L and canine 16S rRNA genes were included in the dqRT-PCR assay to detect CPIV and monitor invalid results throughout the qRT-PCR process. The developed dqRT-PCR assay specifically detected CPIV5 but no other canine pathogens. Furthermore, 16S rRNA was stably amplified by dqRT-PCR assay in all samples containing canine cellular materials. The assay's sensitivity was determined as below ten RNA copies per reaction, with CPIV5 L gene standard RNA and 1 TCID₅₀/mL with the CPIV5 D008 vaccine strain, which was 10-fold higher than that of the previous HN gene-specific qRT-PCR (HN-qRT-PCR) assays and was equivalent to that of the previous N gene-specific qRT-PCR (N-qRT-PCR) assays, respectively. Moreover, the Ct values of the CPIV5-positive samples obtained using the dqRT-PCR assay were lower than those obtained using the previous HN- and N-qRT-PCR assays, indicating that the diagnostic performance of the dqRT-PCR assay was superior to those of previous HN- and N-qRT-PCR assays. The calculated Cohen's kappa coefficient values (95% confidence interval) between dqRT-PCR and the HN- or N-specific qRT-PCR assays were 0.97 (0.90-1.03) or 1.00 (1.00-1.00), respectively. In conclusion, the newly developed dqRT-PCR assay with high sensitivity, specificity, and reliability will be a promising diagnostic tool for the detection of CPIV5 in clinical samples and useful for etiological and epidemiological studies of CPIV5 infection in dogs.

Molecular Detection of Porcine Parainfluenza Viruses 1 and 5 Using a Newly Developed Duplex Real-Time RT-PCR in South Korea

Two species of porcine parainfluenza viruses (PPIV), PPIV1 and PPIV5, are globally distributed in pig herds and associated with porcine respiratory diseases, and a diagnostic tool for the simultaneous detection of the two viruses is required. In this study, a TaqMan probe-based duplex real-time reverse transcription polymerase chain reaction (dqRT-PCR) assay was first developed for the differential detection of PPIV1 and PPIV5 nucleocapsid protein (NP) genes in porcine clinical samples. The dqRT-PCR assay was highly sensitive, its limit of detection was approximately 10 RNA copies/reaction, it specifically amplified the targeted NP genes of PPIV1 and PPIV5 without cross-reacting with other porcine pathogens, and their clinical detection rates were 15.2% and 0.7%, respectively. The results from 441 clinical samples taken from 278 Korean domestic pig farms showed that the prevalence of PPIV1 and PPIV5 was 11.2% and 1.1%, respectively, and co-infection of both viruses was confirmed in a farm, suggesting that PPIV1 and PPIV5 are co-circulating in current Korean pig herds. Phylogenetic analysis based on the partial NP genes suggested that genetically diverse PPIV1 strains are circulating in Korean pig herds. The developed dqRT-PCR assay was found to be an accurate, reliable, and quantitative detection tool for PPIV1 and PPIV5 RNA in clinical pig samples and will be useful for etiological and epidemiological studies and the control of viral infections in the field.

Paramyxoviruses from bats: changes in receptor specificity and their role in host adaptation

Global metagenomic surveys have revealed that bats host a diverse array of paramyxoviruses, including species from at least five major genera. An essential determinant of successful spillover is the entry of a virus into a new host. We evaluate the role of receptor usage in the zoonotic potential of bat-borne henipaviruses, morbilliviruses, pararubulaviruses, orthorubulaviruses, and jeilongviruses; successful spillover into humans depends upon compatibility of a respective viral attachment protein with its cognate receptor. We also emphasize the importance of postentry restrictions in preventing spillover. Metagenomics and characterization of newly identified paramyxoviruses have greatly improved our understanding of spillover determinants, allowing for better forecasts of which bat-borne viruses may pose the greatest risk for cross-species transmission into humans.

Pathogenesis of wild-type- and vaccine-based recombinant peste des petits ruminants virus (PPRV) expressing EGFP in experimentally infected domestic goats

Peste des petits ruminants virus (PPRV) is a highly contagious morbillivirus related to measles and canine distemper virus, mostly affecting small ruminants. The corresponding PPR disease has a high clinical impact in goats and is characterized by fever, oral and nasal erosions, diarrhoea and pneumonia. In addition, massive infection of lymphoid tissues causes lymphopaenia and immune suppression. This results in increased susceptibility to secondary bacterial infections, explaining the observed high mortality in some outbreaks. We studied the pathogenesis of PPR by experimental inoculation of Dutch domestic goats with a recombinant virulent PPRV strain modified to express EGFP and compared it to an EGFP-expressing vaccine strain of PPRV. After intratracheal inoculation with virulent PPRV, animals developed fever, viraemia and leucopaenia, and shed virus from the respiratory and gastro-intestinal tracts. Macroscopic evaluation of fluorescence at the peak of infection 7 days post-inoculation (dpi) showed prominent PPRV infection of the respiratory tract, lymphoid tissues, gastro-intestinal tract, mucosae and skin. Flow cytometry of PBMCs collected over time demonstrated a cell-associated viraemia mediated by infected lymphocytes. At 14 dpi, pathognomonic zebra stripes were detected in the mucosa of the large intestine. In contrast, vaccine strain-inoculated goats remained largely macroscopically fluorescence negative and did not present clinical signs. A low-level viraemia was detected by flow cytometry, but at necropsy no histological lesions were observed. Animals from both groups seroconverted as early as 7 dpi and sera efficiently neutralized virulent PPRV in vitro. Combined, this work presents a study of the pathogenesis of wild type- and vaccine-based PPRV in its natural host. This study shows the strength of recombinant EGFP-expressing viruses in fluorescence-guided pathogenesis studies.

The C-Terminal 300 Amino Acid Residues of the G Protein and Putative Open Reading Frame X of the G Gene of Tailam Paramyxovirus (TlmPV) Are Not Required for Replication in Tissue Culture Cells

Tailam paramyxovirus (TlmPV) was identified in Sikkim Rats in Hong Kong, China in 2011. Its negative sense RNA genome is similar to J paramyxovirus (JPV) and Beilong paramyxovirus (BeiPV), the prototypes of the recently established genus Jeilongvirus. TlmPV genome is predicted to have eight genes in the order 3'-N-P/V/C-M-F-SH-TM-G/X-L-5'. The predicted size of the TlmPV G protein is 1,052 amino acid (aa) residues and much larger than G proteins of typical paramyxoviruses, which are often less than 800 aa. In addition to G open reading frame (ORF) in the G gene, another ORF, termed ORF-X exists in the G gene transcript. Similar ORF-X exists in JPV and BeiPV G gene, but their expression in virus-infected cells has not been confirmed. In this study, we generated infectious TlmPV using a newly developed reverse genetics system. We have found that the G protein of TlmPV is truncated in cultured cells: stop codons emerged in the G open reading frame, resulting in deletions of amino acid residues beyond residue 732. We have obtained infectious TlmPV lacking the C-terminal 307 aa (rTlmPV-G745) and TlmPV lacking the C-terminal 306 aa and the ORF-X (rTlmPV-GΔ746-X). The recombinant TlmPVs lacking the C-terminal 300 aa reach a higher peak viral titer and have improved genome stability in tissue cultured cells. The work indicates that the C-terminal of the G protein of TlmPV and ORF-X are not required for replication in tissue culture cells, and the deletion of the C-terminal confers a growth advantage in tissue culture cells. IMPORTANCE TlmPV is a member of the recently established genus Jeilongvirus. TlmPV encodes a large G protein and its G gene contains ORF-X. In this work, infectious TlmPV was recovered using reverse genetics. Using this system, we have demonstrated that 300 aa of C-terminal of G and the ORF-X are not required for viral replication in tissue culture cells.

Quasispecies Nature of RNA Viruses: Lessons from the Past

Viral quasispecies are distinct but closely related mutants formed by the disparity in viral genomes due to recombination, mutations, competition, and selection pressure. Theoretical derivation for the origin of a quasispecies is owed to the error-prone replication by polymerase and mutants of RNA replicators. Here, we briefly addressed the theoretical and mathematical origin of quasispecies and their dynamics. The impact of quasispecies for major salient human pathogens is reviewed. In the current global scenario, rapid changes in geographical landscapes favor the origin and selection of mutants. It comes as no surprise that a cauldron of mutants poses a significant risk to public health, capable of causing pandemics. Mutation rates in RNA viruses are magnitudes higher than in DNA organisms, explaining their enhanced virulence and evolvability. RNA viruses cause the most devastating pandemics; for example, members of the Orthomyxoviridae family caused the great influenza pandemic (1918 flu or Spanish flu), the SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome) outbreak, and the human immunodeficiency viruses (HIV), lentiviruses of the Retroviridae family, caused worldwide devastation. Rapidly evolving RNA virus populations are a daunting challenge for the designing of effective control measures like vaccines. Developing awareness of the evolutionary dispositions of RNA viral mutant spectra and what influences their adaptation and virulence will help curtail outbreaks of past and future pathogens.

Genetic diversity of Newcastle disease viruses circulating in wild and synanthropic birds in Ukraine between 2006 and 2015

Newcastle disease virus (NDV) infects a wide range of bird species worldwide and is of importance to the poultry industry. Although certain virus genotypes are clearly associated with wild bird species, the role of those species in the movement of viruses and the migratory routes they follow is still unclear. In this study, we performed a phylogenetic analysis of nineteen NDV sequences that were identified among 21,924 samples collected from wild and synanthropic birds from different regions of Ukraine from 2006 to 2015 and compared them with isolates from other continents. In synanthropic birds, NDV strains of genotype II, VI, VII, and XXI of class II were detected. The fusion gene sequences of these strains were similar to strains detected in birds from different geographical regions of Europe and Asia. However, it is noteworthy to mention the isolation of vaccine viruses from synanthropic birds, suggesting the possibility of their role in viral transmission from vaccinated poultry to wild birds, which may lead to the further spreading of vaccine viruses into other regions during wild bird migration. Moreover, here we present the first publicly available complete NDV F gene from a crow (genus Corvus). Additionally, our phylogenetic results indicated a possible connection of Ukrainian NDV isolates with genotype XXI strains circulating in Kazakhstan. Among strains from wild birds, NDVs of genotype 1 of class I and genotype I of class II were detected. The phylogenetic analysis highlighted the possible exchange of these NDV strains between wild waterfowl from the Azov-Black Sea region of Ukraine and waterfowl from different continents, including Europe, Asia, and Africa.

Pseudotyped Virus for Henipavirus

The genus Henipavirus (HNV) includes two virulent infectious viruses, Nipah virus (NiV) and Hendra virus (HeV), which are the focus of considerable public health research efforts and have been classified as priority infectious diseases by the World Health Organization. Both viruses are high risk and should be handled in biosafety level 4 laboratories. Pseudotyped viruses containing the envelope proteins of HNV viruses have the same envelope protein structure as the authentic viruses; thus, they can mimic the receptor-binding and membrane fusion processes of authentic viruses with host cells and can be handled in biosafety level 2 laboratories. These characteristics enable pseudotyped viruses to be widely used in studies of viral infection mechanisms (packaging, budding, virus attachment, membrane fusion, viral entry, and glycosylation), inhibitory drug screening assays, and monoclonal antibody neutralization characteristics. This review will provide an overview of the progress of research concerning pseudotyped virus packaging systems for NiV and HeV.

Parainfluenza and corona viruses in a fallow deer (Dama dama) with fatal respiratory disease

Parainfluenza virus type 3 (PIV-3) and coronaviruses (CoV) are commonly found in respiratory tracts of ruminants and capable of causing clinical disease. Here, we investigated the cause of ill-thrift and sudden death in a five-month-old male fallow deer which occurred in December 2019. The calf was one of the five calves in a herd of 170 deer that, along with three adult hinds, died during a 2-week period. The deer calves were in a shed, sharing airspace with young cattle that had been reported to be coughing. Significant gross pathology was observed in the respiratory and alimentary tracts of the deer calf and histopathology of the lung and trachea was suggestive of likely involvement of PIV-3. Strong and specific cytoplasmic labeling of bronchiolar epithelium and terminal airway, alike those seen with PIV-3 pneumonia in cattle, was observed using a polyclonal bovine PIV-3 antibody. Metagenomic analysis detected a PIV-3 and a CoV in the lung tissue. The PIV-3 L protein gene had the highest sequence identity with those of bovine PIV-3 (83.1 to 98.4%) and phylogenetically clustered with bovine PIV-3 in the genotype C. The CoV spike protein gene shared 96.7% to 97.9% sequence identity with those of bovine CoVs, but only 53.1% identity with SARS-CoV-2 reference virus. We believe this is the first report of PIV-3 and CoV co-infection in fallow deer and their association with fatal pneumonia; major pathology caused by PIV-3.

Novel and classical morbilliviruses: Current knowledge of three divergent morbillivirus groups

Currently, seven species of morbillivirus have been classified. Six of these species (Measles morbillivirus, Rinderpest morbillivirus, Small ruminant morbillivirus, Canine morbillivirus, Phocine morbillivirus, and Cetacean morbillivirus) are highly infectious and cause serious systemic diseases in humans, livestock, domestic dogs, and wild animals. These species commonly use the host proteins signaling lymphocytic activation molecule (SLAM) and nectin-4 as receptors, and this usage contributes to their virulence. The seventh species (Feline morbillivirus: FeMV) is phylogenetically divergent from the six SLAM-using species. FeMV differs from the SLAM-using morbillivirus group in pathogenicity and infectivity, and is speculated to use non-SLAM receptors. Recently, novel species of morbilliviruses have been discovered in bats, rodents, and domestic pigs. Because the ability to use SLAM and nectin-4 is closely related to the infectivity and pathogenicity of morbilliviruses, investigation of the potential usage of these receptors is useful for estimating infectivity and pathogenicity. The SLAM-binding sites in the receptor-binding protein show high similarity among the SLAM-using morbilliviruses. This feature may help to estimate whether novel morbillivirus species can use SLAM as a receptor. A novel morbillivirus species isolated from wild mice diverged from the classified morbilliviruses in the phylogenetic tree, forming a third group separate from the SLAM-using morbillivirus group and FeMV. This suggests that the novel rodent morbillivirus may exhibit a different risk from the SLAM-using morbillivirus group, and analyses of its viral pathogenicity and infectivity toward humans are warranted.

Immunogenicity of a recombinant hemagglutinin neuraminidase-Porcine rubulavirus produced by Escherichia coli of Porcine rubulavirus gives protective immunity of litter after challenge

Porcine rubulavirus (PRV) is a contagious virus that affects the Mexican swine industry. This work aimed to evaluate the immunogenicity of an recombinant hemagglutinin neuraminidase-Porcine rubulavirus (rHN-PorPV) candidate vaccine on pregnant sows, and the protective efficacy afforded to their 7-day-old suckling piglets against PRV lethal challenge. Three sows were immunized with rHN-PorPV formulated with immune-stimulating complex (ISCOMs) and two sows with rHN-PorPV protein alone as well as a mock-immunized pregnant sow (negative control). Quantitative ELISA detected a high concentration of anti-rHN-PorPV Immunoglobulin G (IgG) antibodies in sow sera after the second dose of vaccine administered on day 14 until farrowing, showing viral-neutralizing and cross-neutralization activity against different variants of PRV. Sera samples from piglets of immunized sows (with or without adjuvant), showed high concentrations of IgG antibodies. As expected, piglets from the negative control sow (n=5), exhibited severe signs of disease and 100% of mortality after PRV challenge study. Conversely, 75% and 87.5% of the piglets born from the rHN-PorPV and the rHN-PorPV-ISCOMs-immunized sows (n=8), survived, respectively, showing milder PRV clinical signs. Our data indicate that rHN-PorPV candidate vaccine produced in Escherichia coli induces efficient humoral response in pregnant sows and that the maternally derived immunity provides high protection to suckling piglets against PRV lethal challenge.

Molecular characterization of Newcastle disease virus vaccines in Nigeria

Background and Aim

Newcastle disease (ND) caused by ND virus (NDV) is a serious impediment to effective poultry production in developing countries such as Nigeria. Despite employing vaccination and other control measures to curtail this disease, its severe forms still persist. This study aimed to confirm the virus strains in the NDV vaccine brands commonly used in Nigeria.

Materials and Methods

We employed reverse-transcription polymerase chain reaction (RT-PCR), sequencing, and sequence analysis to characterize NDV strains in four NDV vaccines commonly used in Nigeria. Fragments of 300 bp from NDV fusion genes from the vaccines were amplified. Polymerase chain reaction products were sequenced and analyzed using multiple sequence alignment and phylogenetic analyses to characterize the vaccine viruses as pathotypes.

Results

All the vaccines gave positive results, confirming the presence of NDV. Multiple sequence alignment and phylogenetic analyses revealed that two of the vaccines had the lentogenic pathotype, while the other two had the mesogenic or velogenic pathotype.

Conclusion

This study provides information to facilitate strategies for regular control of the quality of vaccines in Nigeria.

The First Report of a Virulent Newcastle Disease Virus of Genotype VII.2 Causing Outbreaks in Chickens in Bangladesh

Newcastle disease (ND) is endemic in poultry in Bangladesh. We performed genotypic and pathotypic characterization of four ND virus (NDV) isolates from recent outbreaks in broiler chickens in Bangladesh during the period of 2020-2021. Phylogenetic analysis based on the complete fusion protein gene coding sequences classified the viruses into NDV class II genotype VII.2 together with viruses from Indonesia isolated between 2014 and 2021 and a single 2020 Indian isolate. Pathogenicity testing using the intracerebral pathogenicity index in day-old chickens and mean embryo death time in embryonating chicken eggs revealed that the Bangladeshi isolates are velogenic. Inoculation of 35-day-old chickens with two NDV isolates (LT67 and N5) resulted in 100% morbidity by 3 days post inoculation (DPI), and all birds succumbed to infection by 7 DPI. Massive hemorrhages, congestion and necrotic lesions were observed in different visceral organs, which were typical for infection with a velogenic viscerotropic pathotype of NDV. At microscopic examination, tracheitis, severe pneumonia, focal proventriculitis, transmural enteritis, focal myocarditis, severe congestion and necrosis in kidneys, and lymphoid depletion in lymphoid tissues were found. Our study reports the first outbreak of the panzootic genotype VII.2 NDV in poultry in Bangladesh and documents a possible recent re-introduction of this NDV genotype from Southeast or East Asia. This study further provides viral distribution and epidemiological data that can facilitate the effective control of NDV.

Paramyxoviruses in rodents: A review

Paramyxoviruses have been shown to infect a wide range of hosts, including rodents, and humans. Several novel murine paramyxoviruses have been discovered in the last several decades. Although these viruses are unclassified, they are recognized as Beilong virus, Mojiang virus (MojV), and Tailam virus in rats, Jeilongvirus, Nariva, Paju Apodemus paramyxovirus-1 and -2 in mice, and Pentlands paramyxovirus-1, -2, and -3 in squirrels. These paramyxoviruses were reported mainly in China and a few other countries like Australia, the Republic of Korea, Trinidad, and France. In June 2012, it becomes a great concern in China whereby, three miners were reported dead potentially caused by a novel zoonotic MojV, a henipa-like virus isolated from tissue samples of rats from the same cave. Rats are considered to be natural hosts for the MojV from the literature research. The classified paramyxovirus, Sendai virus in rodents is also reviewed. Paramyxoviruses infection in rodents leads to respiratory distress such as necrotizing rhinitis, tracheitis, bronchiolitis, and interstitial pneumonia. Infections caused by paramyxoviruses often spread between species, manifesting disease in spillover hosts, including humans. This review focuses on the paramyxoviruses in rodents, including the epidemiological distributions, transmission and pathogenesis, clinical manifestations, diagnostic methods, and control and prevention of paramyxoviruses infection to provide a better understanding of these highly mutating viruses.

Human parainfluenza 2 &amp; 4: Clinical and genetic epidemiology in the UK, 2013-2017, reveals distinct disease features and co-circulating genomic subtypes

BACKGROUND

Human Parainfluenza viruses (HPIV) comprise of four members of the genetically distinct genera of Respirovirus (HPIV1&amp;3) and Orthorubulavirus (HPIV2&amp;4), causing significant upper and lower respiratory tract infections worldwide, particularly in children. However, despite frequent molecular diagnosis, they are frequently considered collectively or with HPIV4 overlooked entirely. We therefore investigated clinical and viral epidemiological distinctions of the relatively less prevalent Orthorubulaviruses HPIV2&amp;4 at a regional UK hospital across four autumn/winter epidemic seasons.

METHODS

A retrospective audit of clinical features of all HPIV2 or HPIV4 RT-PCR-positive patients, diagnosed between 1st September 2013 and 12th April 2017 was undertaken, alongside sequencing of viral genome fragments in a representative subset of samples.

RESULTS

Infection was observed across all age groups, but predominantly in children under nine and adults over 40, with almost twice as many HPIV4 as HPIV2 cases. Fever, abnormal haematology, elevated C-reactive protein and hospital admission were more frequently seen in HPIV2 than HPIV4 infection. Each of the four seasonal peaks of either HPIV2, HPIV4 or both, closely matched that of RSV, occurring in November and December and preceding that of Influenza A. A subset of viruses were partially sequenced, indicating co-circulation of multiple subtypes of both HPIV2&amp;4, but with little variation between each epidemic season or from limited global reference sequences.

CONCLUSIONS

Despite being closest known genetic relatives, our data indicates a potential difference in associated disease between HPIV2 and HPIV4, with more hospitalisation seen in HPIV2 mono-infected individuals, but a greater overall number of HPIV4 cases.

First report of Porcine respirovirus 1 in South Korea

Porcine respirovirus 1 (PRV1) is a recently emerging porcine respiratory virus that belongs to the genus Respirovirus of the Paramyxoviridae family. Since its first detection in Hong Kong, China in 2009, PRV1 has been subsequently identified in several American and European countries, suggesting that the emerging virus may have been globally distributed. However, in Asia, the virus has been reported only in China. Here, we report that PRV1 was first detected in pigs from 16 farms located in seven provinces across Korea, with a prevalence of 71.4% based on the tested oral fluid samples, suggesting that the virus is already widespread in Korean pig herds. For further genetic characterization of the Korean PRV1 strains, a complete genome and two F gene sequences were obtained from PRV1-positive samples collected from three different pig farms. Phylogenetic analysis based on the complete genome and F gene sequences showed that all three Korean PRV1 strains were grouped into European lineage 1 and were closely related to strains from Hong Kong (China), Germany and Poland. We could not obtain evidence for the origin of Korean PRV1 because of the limited availability of PRV1 sequences. In conclusion, PRV1 was first identified in Korean pig herds and genetically characterized in the present study. These results contribute to a better understanding of the global geographical distribution and genetic characteristics of PRV1.

Prevalence and genetic diversity of coronaviruses, astroviruses and paramyxoviruses in wild birds in southeastern Kazakhstan

Wild birds are natural reservoirs of many emerging viruses, including some zoonoses. Considering that the territory of Kazakhstan is crossed by several bird migration routes, it is important to know pathogenic viruses circulating in migratory birds in this region. Therefore, the aim of this study was to identify the host range, diversity and spatial distribution of avian paramyxoviruses, coronaviruses, and astroviruses in free-ranging wild birds in the southeastern region of Kazakhstan. For this purpose, we collected tracheal and cloacal swabs from 242 wild birds belonging to 51 species and screened them using conventional PCR assays. Overall, 4.1% (10/242) and 2.9% (7/242) of all examined birds tested positive for coronaviruses and astroviruses, respectively. Coronaviruses were found in the orders Pelecaniformes (30%; 3/10), Charadriiformes (30%; 3/10), Columbiformes (20%; 2/10), Anseriformes (10%; 1/10), and Passeriformes (10%; 1/10). All detected strains belonged to the genus Gammacoronavirus. Astroviruses were detected in birds representing the orders Passeriformes (57%; 4/7), Coraciiformes (14%; 1/7), Charadriiformes (14%; 1/7), and Columbiformes (14%; 1/7). Paramyxoviruses were observed in only two birds (0.8%; 2/242). Both strains were closely related to the species APMV-22, which had not been previously detected in Kazakhstan. Phylogenetic analysis of the partial RdRp gene sequences of the virus strains revealed three different clades of astroviruses, two clades of coronaviruses, and one clade of paramyxoviruses. The results of this study provide valuable information on the diversity and spatial distribution of paramyxoviruses, coronaviruses, and astroviruses in wild birds in southeastern Kazakhstan and highlight the importance of further thorough monitoring of wild birds in this region.

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First study on CoVs and AstroVs in wild birds in Kazakhstan.

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APMVs, CoVs and AstroVs are confirmed by RT-PCR and partial RdRp gene sequencing.

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The CoVs prevalence is higher in aquatic birds as compared to terrestrial species.

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The obtained CoV strains belong to the genus Gammacoronavirus

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Strains closely related to APMV-22 not previously detected in Kazakhstan are shown.

A South American Mouse Morbillivirus Provides Insight into a Clade of Rodent-Borne Morbilliviruses

Morbilliviruses are negative-sense single-stranded monosegmented RNA viruses in the family Paramyxoviridae (order Mononegavirales). Morbilliviruses infect diverse mammals including humans, dogs, cats, small ruminants, seals, and cetaceans, which serve as natural hosts. Here, I report the identification and characterization of novel viruses detected in public RNAseq datasets of South American long-haired and olive field mice. The divergent viruses dubbed Ratón oliváceo morbillivirus (RoMV) detected in renal samples from mice collected from Chile and Argentina are characterized by an unusually large genome including long intergenic regions and the presence of an accessory protein between the F and H genes redounding in a genome architecture consisting in 3'-N-P/V/C-M-F-hp-H-L-5'. Structural and functional annotation, genetic distance, and evolutionary insights suggest that RoMV is a member of a novel species within genus Morbillivirus tentatively named as South American mouse morbillivirus. Phylogenetic analysis suggests that this mouse morbillivirus is closely related to and clusters into a monophyletic group of novel rodent-borne morbilliviruses. This subclade of divergent viruses expands the host range, redefines the genomic organization and provides insights on the evolutionary history of genus Morbillivirus.

Nucleolar Protein Treacle Is Important for the Efficient Growth of Mumps Virus

The nucleolus is the largest structure in the nucleus, and it plays roles in mediating cellular stress responses and regulating cell proliferation, as well as in ribosome biosynthesis. The nucleolus is composed of a variety of nucleolar factors that interact with each other in a complex manner to enable its function. Many viral proteins interact with nucleolar factors as well, affecting cellular morphology and function. Here, to investigate the association between mumps virus (MuV) infection and the nucleolus, we evaluated the necessity of nucleolar factors for MuV proliferation by performing a knockdown of these factors with small interfering (si)RNAs. Our results reveal that suppressing the expression of Treacle, which is required for ribosome biosynthesis, reduced the proliferative potential of MuV. Additionally, the one-step growth kinetics results indicate that Treacle knockdown did not affect the viral RNA and protein synthesis of MuV, but it did impair the production of infectious virus particles. Viral matrix protein (M) was considered a candidate Treacle interaction partner because it functions in the process of particle formation in the viral life cycle and is partially localized in the nucleolus. Our data confirm that MuV M can interact with Treacle and colocalize with it in the nucleolus. Furthermore, we found that viral infection induces relocalization of Treacle in the nucleus. Together, these findings suggest that interaction with Treacle in the nucleolus is important for the M protein to exert its functions late in the MuV life cycle. IMPORTANCE The nucleolus, which is the site of ribosome biosynthesis, is a target organelle for many viruses. It is increasingly evident that viruses can favor their own replication and multiplication by interacting with various nucleolar factors. In this study, we found that the nucleolar protein Treacle, known to function in the transcription and processing of pre-rRNA, is required for the efficient propagation of mumps virus (MuV). Specifically, our data indicate that Treacle is not involved in viral RNA or protein synthesis but is important in the processes leading to viral particle production in MuV infection. Additionally, we determined that MuV matrix protein (M), which functions mainly in viral particle assembly and budding, colocalized and interacted with Treacle. Furthermore, we found that Treacle is distributed throughout the nucleus in MuV-infected cells. Our research shows that the interaction between M and Treacle supports efficient viral growth in the late stage of MuV infection.

First Genomic Evidence of a Henipa-like Virus in Brazil

The viral genus Henipavirus includes two highly virulent zoonotic viruses of serious public health concern. Hendra henipavirus and Nipah henipavirus outbreaks are restricted to Australia and Southeast Asia, respectively. The Henipavirus genus comprises mostly bat-borne viruses, but exceptions have already been described as novel viruses with rodents and shrews as reservoir animals. In the Americas, scarce evidence supports the circulation of these viruses. In this communication, we report a novel henipa-like virus from opossums (Marmosa demerarae) from a forest fragment area in the Peixe-Boi municipality, Brazil, after which the virus was named the Peixe-Boi virus (PBV). The application of next-generation sequencing and metagenomic approach led us to discover the original evidence of a henipa-like virus genome in Brazil and South America and the original description of a henipa-like virus in marsupial species. These findings emphasize the importance of further studies to characterize PBV and clarify its ecology, impact on public health, and its relationship with didelphid marsupials and henipaviruses.

Discovery and Genomic Characterization of a Novel Henipavirus, Angavokely Virus, from Fruit Bats in Madagascar

The genus Henipavirus (family Paramyxoviridae) currently comprises seven viruses, four of which have demonstrated prior evidence of zoonotic capacity. These include the biosafety level 4 agents Hendra (HeV) and Nipah (NiV) viruses, which circulate naturally in pteropodid fruit bats. Here, we describe and characterize Angavokely virus (AngV), a divergent henipavirus identified in urine samples from wild, Madagascar fruit bats. We report the nearly complete 16,740-nucleotide genome of AngV, which encodes the six major henipavirus structural proteins (nucleocapsid, phosphoprotein, matrix, fusion, glycoprotein, and L polymerase). Within the phosphoprotein (P) gene, we identify an alternative start codon encoding the AngV C protein and a putative mRNA editing site where the insertion of one or two guanine residues encodes, respectively, additional V and W proteins. In other paramyxovirus systems, C, V, and W are accessory proteins involved in antagonism of host immune responses during infection. Phylogenetic analysis suggests that AngV is ancestral to all four previously described bat henipaviruses-HeV, NiV, Cedar virus (CedV), and Ghanaian bat virus (GhV)-but evolved more recently than rodent- and shrew-derived henipaviruses, Mojiang (MojV), Gamak (GAKV), and Daeryong (DARV) viruses. Predictive structure-based alignments suggest that AngV is unlikely to bind ephrin receptors, which mediate cell entry for all other known bat henipaviruses. Identification of the AngV receptor is needed to clarify the virus's potential host range. The presence of V and W proteins in the AngV genome suggest that the virus could be pathogenic following zoonotic spillover. IMPORTANCE Henipaviruses include highly pathogenic emerging zoonotic viruses, derived from bat, rodent, and shrew reservoirs. Bat-borne Hendra (HeV) and Nipah (NiV) are the most well-known henipaviruses, for which no effective antivirals or vaccines for humans have been described. Here, we report the discovery and characterization of a novel henipavirus, Angavokely virus (AngV), isolated from wild fruit bats in Madagascar. Genomic characterization of AngV reveals all major features associated with pathogenicity in other henipaviruses, suggesting that AngV could be pathogenic following spillover to human hosts. Our work suggests that AngV is an ancestral bat henipavirus that likely uses viral entry pathways distinct from those previously described for HeV and NiV. In Madagascar, bats are consumed as a source of human food, presenting opportunities for cross-species transmission. Characterization of novel henipaviruses and documentation of their pathogenic and zoonotic potential are essential to predicting and preventing the emergence of future zoonoses that cause pandemics.

Micro-Players of Great Significance-Host microRNA Signature in Viral Infections in Humans and Animals

Over time, more and more is becoming known about micro-players of great significance. This is particularly the case for microRNAs (miRNAs; miR), which have been found to participate in the regulation of many physiological and pathological processes in both humans and animals. One such process is viral infection in humans and animals, in which the host miRNAs—alone or in conjunction with the virus—interact on two levels: viruses may regulate the host’s miRNAs to evade its immune system, while the host miRNAs can play anti- or pro-viral roles. The purpose of this comprehensive review is to present the key miRNAs involved in viral infections in humans and animals. We summarize the data in the available literature, indicating that the signature miRNAs in human viral infections mainly include 12 miRNAs (i.e., miR-155, miR-223, miR-146a, miR-122, miR-125b, miR-132, miR-34a, miR -21, miR-16, miR-181 family, let-7 family, and miR-10a), while 10 miRNAs are commonly found in animals (i.e., miR-155, miR-223, miR-146a, miR-145, miR-21, miR-15a/miR-16 cluster, miR-181 family, let-7 family, and miR-122) in this context. Knowledge of which miRNAs are involved in different viral infections and the biological functions that they play can help in understanding the pathogenesis of viral diseases, facilitating the future development of therapeutic agents for both humans and animals.

Screening of Healthy Feral Pigeons (Columba livia domestica) in the City of Zurich Reveals Continuous Circulation of Pigeon Paramyxovirus-1 and a Serious Threat of Transmission to Domestic Poultry

Pigeon paramyxovirus-1 (PPMV-1) is predominantly isolated from pigeons or doves and forms a separate group of viral strains within Avian Orthoavulavirus-1, the causative agent of Newcastle disease in poultry. Since the introduction of PPMV-1 into Europe in 1981, these strains have rapidly spread all over Europe, and are nowadays considered to be enzootic in feral and hobby pigeons (Columba livia domestica). Infections with PPMV-1 can range from asymptomatic to fatal. To assess whether PPMV-1 continuously circulates in healthy feral pigeons, 396 tissue samples of pigeons from the city of Zurich were tested by reverse transcriptase real-time PCR over the period of one year. PPMV-1-RNA was detected in 41 feral pigeons (10.35%), determined as the dominant European genotype VI.2.1.1.2.2. In 38 of the 41 pigeons where organ samples tested positive, PPMV-1-RNA was also detected in either choana or cloaca swabs. There were no significant differences in positivity rates between seasons, age, and sex. The current study shows that feral pigeons without clinical signs of disease can harbour and most likely excrete PPMV-1. Spill-over into free-range holdings of chickens are therefore possible, as observed in a recent outbreak of Newcastle disease in laying hens due to PPMV-1 genotype VI.2.1.1.2.2. in the canton of Zurich in January 2022.

Breakthrough Infections: A Challenge towards Measles Elimination?

Measles is one of the most contagious diseases known to man. Despite the existence of a safe and effective live attenuated vaccine, measles can appear in vaccinated individuals. Paradoxically, breakthrough cases increase as vaccination coverage in the general population rises. In measles endemic areas, breakthrough cases represent less than 10% of total infections, while in areas with high vaccination coverage these are over 10% of the total. Two different vaccination failures have been described: primary vaccination failure, which consists in the complete absence of humoral response and occurs in around 5% of vaccinated individuals; and secondary vaccination failure is due to waning immunity or incomplete immunity and occurs in 2–10% of vaccinees. Vaccination failures are generally associated with lower viral loads and milder disease (modified measles) since vaccination limits the risk of complicated disease. Vaccination failure seems to occur between six and twenty-six years after the last vaccine dose administration. This review summarizes the literature about clinical, serological, epidemiological, and molecular characteristics of measles breakthrough cases and their contribution to virus transmission. In view of the measles elimination goal, the assessment of the potential decline in antibody protection and the targeted implementation of catch-up vaccination are essential.

Epidemiological surveillance of Newcastle disease virus in Egypt - a 6-year cohort study

Newcastle disease (ND) is one of the most important poultry diseases worldwide and can lead to annual losses of up to 80% of backyard chickens in Africa. A retrospective cohort of 6 years was planned to screen the NDV in intensive chicken and turkey flocks. The existence of velogenic NDV strain was screened in different poultry flocks showing suspected signs of NDV using real-time RT-PCR targeting the F gene of the velogenic strain. A total of 843 poultry flocks were screened during the cohort. Samples were classified based on the month and year as well as the poultry type. All flocks should be negative for avian influenza virus as an inclusion criterion of the study. The F gene of a randomly selected positive sample from each year as well as an archival sample from 2005 was sequenced. An overall of 52.4% (443/842) of the tested farms showed positive results for the velogenic NDV. The cumulative percentage of positive flocks to the total positive flocks per month ranged from 5.9 to 11.8%. The results revealed that NDV is circulating across all months annually without evidence of seasonal tendency of the disease. Most of the strains belong to genotype VII.1.1, with only two strains related to XXI.1.1 and XXI.2. All VII.1.1 strains possess arginine at 27 position while XXI.1.1 and XXI.2 strains showed cysteine at 27 and amino acid substitutions in the signal peptide, cleavage site, and neutralizing epitopes. In conclusion, the current molecular epidemiological surveillance confirms the enzootic nature of NDV. It circulates all year round with no evidence of seasonal incidence. Genotype VII is the most predominant NDV genotype in Egypt.

Coinfection kinetics of goatpox virus and peste-des-petits-ruminants virus in Vero cells

Goatpox, sheeppox, and peste-des-petits-ruminants (PPR) are economically important virus diseases affecting goats and sheep, which often cause coinfection/comorbidities in the field. Coinfection with these viruses leads to enhanced infection in natural scenarios in terms of morbidities and mortalities. Currently, individual live attenuated vaccines are being used to mitigate these diseases and research on combination vaccines for these diseases is encouraging. For the preparation of combination vaccines, vaccine strains of the peste-des-petits-ruminants virus (PPRV), goatpox virus (GTPV), and sheeppox virus (SPPV) are grown separately and GTPV + PPRV are mixed for vaccination of goats, and PPRV + SPPV for sheep. Growing capripox and PPRV strains in the same cells simultaneously without the titer loss will save the time and cost of production. In the current study, we have evaluated the coinfection kinetics of capripox virus and a PPRV using a candidate GTPV vaccine strain (originally caused infection in both goats and sheep in the field) and PPRV/Sungri/96 (vaccine strain) in Vero cells. At high multiplicity of infection (MOI), PPRV was excluded from coinfection by GTPV, whereas at a low multiplicity coexistence/accommodation was observed between PPRV and GTPV without loss of the titer. The results shed light on the possibility of the production of two vaccine strains in the same cells using the coinfection model economically.

Measles and Nipah virus assembly: Specific lipid binding drives matrix polymerization

Measles virus, Nipah virus, and multiple other paramyxoviruses cause disease outbreaks in humans and animals worldwide. The paramyxovirus matrix (M) protein mediates virion assembly and budding from host cell membranes. M is thus a key target for antivirals, but few high-resolution structures of paramyxovirus M are available, and we lack the clear understanding of how viral M proteins interact with membrane lipids to mediate viral assembly and egress that is needed to guide antiviral design. Here, we reveal that M proteins associate with phosphatidylserine and phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] at the plasma membrane. Using x-ray crystallography, electron microscopy, and molecular dynamics, we demonstrate that PI(4,5)P2 binding induces conformational and electrostatic changes in the M protein surface that trigger membrane deformation, matrix layer polymerization, and virion assembly.

Intranasal administration of a live-attenuated recombinant newcastle disease virus expressing the SARS-CoV-2 Spike protein induces high neutralizing antibody levels and protects from experimental challenge infection in hamsters

The emergence of SARS-CoV-2 in December 2019 resulted in the COVID-19 pandemic. Recurring disease outbreaks repeatedly overloaded the public health sector and severely affected the global economy. We developed a candidate COVID-19 vaccine based on a recombinant Newcastle disease virus (NDV) vaccine vector, encoding a pre-fusion stabilized full-length Spike protein obtained from the original SARS-CoV-2 Wuhan isolate. Vaccination of hamsters by intra-muscular injection or intra-nasal instillation induced high neutralizing antibody responses. Intranasal challenge infection with SARS-CoV-2 strain Lelystad demonstrated that both vaccination routes provided partial protection in the upper respiratory tract, and almost complete protection in the lower respiratory tract, as measured by suppressed viral loads and absence of histological lung lesions. Activity wheel measurements demonstrated that animals vaccinated by intranasal inoculation rapidly recovered to normal activity. NDV constructs encoding the spike of SARS-CoV-2 may be attractive candidates for development of intra-nasal COVID-19 booster vaccines.

Classification of new morbillivirus and jeilongvirus sequences from bats sampled in Brazil and Malaysia

As part of a broad One Health surveillance effort to detect novel viruses in wildlife and people, we report several paramyxovirus sequences sampled primarily from bats during 2013 and 2014 in Brazil and Malaysia, including seven from which we recovered full-length genomes. Of these, six represent the first full-length paramyxovirid genomes sequenced from the Americas, including two that are the first full-length bat morbillivirus genome sequences published to date. Our findings add to the vast number of viral sequences in public repositories, which have been increasing considerably in recent years due to the rising accessibility of metagenomics. Taxonomic classification of these sequences in the absence of phenotypic data has been a significant challenge, particularly in the subfamily Orthoparamyxovirinae, where the rate of discovery of novel sequences has been substantial. Using pairwise amino acid sequence classification (PAASC), we propose that five of these sequences belong to members of the genus Jeilongvirus and two belong to members of the genus Morbillivirus. We also highlight inconsistencies in the classification of Tupaia virus and Mòjiāng virus using the same demarcation criteria and suggest reclassification of these viruses into new genera. Importantly, this study underscores the critical importance of sequence length in PAASC analysis as well as the importance of biological characteristics such as genome organization in the taxonomic classification of viral sequences.

The Characterization of Multiple Novel Paramyxoviruses Highlights the Diverse Nature of the Subfamily Orthoparamyxovirinae

The subfamily Orthoparamyxovirinae is a group of single-stranded, negative-sense RNA viruses that contains many human, animal, and zoonotic pathogens. While there are currently only forty-two recognized species in this subfamily, recent research has revealed that much of its diversity remains to be characterized. Using a newly developed nested PCR-based screening assay, we report here the discovery of fifteen orthoparamyxoviruses in rodents and shrews from Belgium and Guinea, thirteen of which are believed to represent new species. Using a combination of nanopore and sanger sequencing, complete genomes could be determined for almost all these viruses, enabling a detailed evaluation of their genome characteristics. While most viruses are thought to belong to the rapidly expanding genus Jeilongvirus, we also identify novel members of the genera Narmovirus, Henipavirus, and Morbillivirus. Together with other recently discovered orthoparamyxoviruses, both henipaviruses and the morbillivirus discovered here appear to form distinct rodent-/shrew-borne clades within their respective genera, clustering separately from all currently classified viruses. In the case of the henipaviruses, a comparison of the different members of this clade revealed the presence of a secondary conserved open reading frame, encoding for a transmembrane protein, within the F gene, the biological relevance of which remains to be established. While the characteristics of the viruses described here shed further light on the complex evolutionary origin of paramyxoviruses, they also illustrate that the diversity of this group of viruses in terms of genome organization appears to be much larger than previously assumed.

Intranasal immunization with avian paramyxovirus type 3 expressing SARS-CoV-2 spike protein protects hamsters against SARS-CoV-2

Current vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are administered parenterally and appear to be more protective in the lower versus the upper respiratory tract. Vaccines are needed that directly stimulate immunity in the respiratory tract, as well as systemic immunity. We used avian paramyxovirus type 3 (APMV3) as an intranasal vaccine vector to express the SARS-CoV-2 spike (S) protein. A lack of pre-existing immunity in humans and attenuation by host-range restriction make APMV3 a vector of interest. The SARS-CoV-2 S protein was stabilized in its prefusion conformation by six proline substitutions (S-6P) rather than the two that are used in most vaccine candidates, providing increased stability. APMV3 expressing S-6P (APMV3/S-6P) replicated to high titers in embryonated chicken eggs and was genetically stable, whereas APMV3 expressing non-stabilized S or S-2P were unstable. In hamsters, a single intranasal dose of APMV3/S-6P induced strong serum IgG and IgA responses to the S protein and its receptor-binding domain, and strong serum neutralizing antibody responses to SARS-CoV-2 isolate WA1/2020 (lineage A). Sera from APMV3/S-6P-immunized hamsters also efficiently neutralized Alpha and Beta variants of concern. Immunized hamsters challenged with WA1/2020 did not exhibit the weight loss and lung inflammation observed in empty-vector-immunized controls; SARS-CoV-2 replication in the upper and lower respiratory tract of immunized animals was low or undetectable compared to the substantial replication in controls. Thus, a single intranasal dose of APMV3/S-6P was highly immunogenic and protective against SARS-CoV-2 challenge, suggesting that APMV3/S-6P is suitable for clinical development.

Performance comparison of homologous and heterologous Newcastle disease virus in vaccines and antibody tests

Antigenic differences between commercial Newcastle Disease Virus (NDV) vaccine and circulating field virus reduce vaccine efficacy. Fifty-layer chickens were divided into five groups: three vaccinated chicken groups using killed LaSota (Genotype II/GII), Mega, or VD (Genotype VII/GVII) viral strains, negative, and positive control groups. On day 28, Hemagglutination Inhibition (HI) serology of vaccinated chickens was performed using whole virus antigens of RIVS, LaSota, Mega, and VD strains. Sera were also tested with an alternative antigen, using an ELISA to detect antibody for the cleavage site F protein peptide from GII and GVII NDV strains. Vaccinated and unvaccinated positive control birds underwent infectious challenges using VD and Mega strains. HI testing showed that antibody titers were higher when tested using homologous antigens than heterologous antigens. ELISA performed with alternative antigens did not perform as well as the established HI test using homologous strains. Viral shedding was reduced by vaccination that was homologous to the infectious challenge in comparison with vaccination using the LaSota strain virus. We conclude that superior results are obtained when serological testing, vaccinations, and vaccine challenge experiments all use circulating strains of ND virus. Implementation of this recommendation would likely reduce viral shedding by vaccinated chickens and be more effective in preventing outbreaks of virulent NDV.

Potential of MicroRNAs As Biomarkers and Therapeutic Targets in Respiratory Viruses: A Literature Review

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression through recognition of cognate sequences and interference of transcriptional, translational, or epigenetic processes. Hundreds of miRNA genes have been found in diverse viruses, and many of these are phylogenetically conserved. Respiratory viruses are the most frequent causative agents of disease in humans, with a significant impact on morbidity and mortality worldwide. Recently, the role of miRNAs in respiratory viral gene regulation, as well as host gene regulation during disease progression, has become a field of interest. This review highlighted the importance of various miRNAs and their potential role in fighting with respiratory viruses as therapeutic molecules with a focus on COVID-19.