BackgroundNext-generation sequencing (NGS) allows ultra-deep sequencing of nucleic acids. The use of sequence-independent amplification of viral nucleic acids without utilization of target-specific primers provides advantages over traditional sequencing methods and allows detection of unsuspected variants and co-infecting agents. However, NGS is not widely used for small RNA viruses because of incorrectly perceived cost estimates and inefficient utilization of freely available bioinformatics tools.MethodsIn this study, we have utilized NGS-based random sequencing of total RNA combined with barcode multiplexing of libraries to quickly, effectively and simultaneously characterize the genomic sequences of multiple avian paramyxoviruses. Thirty libraries were prepared from diagnostic samples amplified in allantoic fluids and their total RNAs were sequenced in a single flow cell on an Illumina MiSeq instrument. After digital normalization, data were assembled using the MIRA assembler within a customized workflow on the Galaxy platform.ResultsTwenty-eight avian paramyxovirus 1 (APMV-1), one APMV-13, four avian influenza and two infectious bronchitis virus complete or nearly complete genome sequences were obtained from the single run. The 29 avian paramyxovirus genomes displayed 99.6% mean coverage based on bases with Phred quality scores of 30 or more. The lower and upper quartiles of sample median depth per position for those 29 samples were 2984 and 6894, respectively, indicating coverage across samples sufficient for deep variant analysis. Sample processing and library preparation took approximately 25–30 h, the sequencing run took 39 h, and processing through the Galaxy workflow took approximately 2–3 h. The cost of all steps, excluding labor, was estimated to be 106 USD per sample.ConclusionsThis work describes an efficient multiplexing NGS approach, a detailed analysis workflow, and customized tools for the characterization of the genomes of RNA viruses. The combination of multiplexing NGS technology with the Galaxy workflow platform resulted in a fast, user-friendly, and cost-efficient protocol for the simultaneous characterization of multiple full-length viral genomes. Twenty-nine full-length or near-full-length APMV genomes with a high median depth were successfully sequenced out of 30 samples. The applied de novo assembly approach also allowed identification of mixed viral populations in some of the samples.Electronic supplementary materialThe online version of this article (doi:10.1186/s12985-017-0741-5) contains supplementary material, which is available to authorized users.

Background: The remarkable diversity and mobility of Newcastle disease viruses (NDV) includes virulent viruses of genotype VI. These viruses are often referred to as pigeon paramyxoviruses 1 because they are normally isolated and cause clinical disease in birds from the Columbidae family. Genotype VI viruses occasionally infect, and may also cause clinical disease in poultry. Thus, the evolution, current spread and detection of these viruses are relevant to avian health.

Virulent viruses of the panzootic Avian avulavirus 1 (AAvV-1) of sub-genotype VIIi were repeatedly isolated (2011-2016) from commercial chickens and from multiple non-poultry avian species in Pakistan. These findings provide evidence for the existence of epidemiological links between Newcastle disease outbreaks in commercial poultry and infections with virulent AAvV-1 strains in other avian species kept in proximity to poultry. Our results suggest that the endemicity of Newcastle disease in Pakistan involves multiple hosts and environments.

Newcastle disease (ND) is a devastating disease and cause high t mortality and morbidity in poultry and nonpoultry avian species worldwide. An intensive vaccination program against ND is a routine practice in Pakistan like other developing countries, but still frequent outbreaks have been recorded in the field. In this study, vaccines prepared from ND viruses corresponding to four different genotypes were compared, to determine if the phylogenetic distance between vaccine and challenge strain influences the protection induced the amount of challenge virus shed. In the experiment, 1-day-old pathogen-free Hubbard chicks were divided into five groups and all groups except control were received live LaSota vaccine. The chicks were re-vaccinated at day 5 and were given oil-adjuvanted inactivated vaccines prepared from one of four different inactivated NDV strains including SFR-55 (genotype-VIIi), Chicken-12 (XIIIb), Mukteswar (III), and LaSota (II), and control group was treated with PBS only. Pre- and post-challenge serum was collected from all groups and tested for antibody against NDV using hemagglutination inhibition (HI) assay. After challenged with virulent SFR-55, the birds were examined daily for morbidity and mortality and were monitored at selected intervals for viral shedding. All the vaccines induced high immune response, and all the groups except the control induced > 84% protection against vNDV challenge. The vaccine genetically and antigeneically similar with challenge NDV strain reduced oral shedding significantly as compared to mismatched strains. From the present study, it was concluded that genotype-matched vaccine has potential to result in better protection by limiting the viral shedding.

Here, we report the complete genome sequence of a virulent Newcastle disease virus (vNDV) strain, duck/Pakistan/Lahore/AW-123/2015, isolated from apparently healthy laying ducks (Anas platyrhynchos domesticus) from the province of Punjab, Pakistan. The virus has a genome length of 15,192 nucleotides and is classified as member of subgenotype VIIi, class II.