Seroprevalence of Newcastle disease virus and avian influenza virus in poultry and captive wild birds in poultry-dense regions of Pakistan.

Newcastle disease virus (NDV) and avian influenza virus (AIV) are causing contagious diseases in chickens and wild birds worldwide; however, there is a paucity of information on the current status of seropositivity of Newcastle and avian influenza diseases in chickens and wild birds of Pakistan. Therefore, the present study aimed to investigate the serological evidence of both diseases in commercial poultry (broiler, layer chickens), backyard poultry, and captive wild birds in poultry­dense regions of Punjab, Pakistan. Enzyme­linked immunosorbent (ELISA) and haemagglutination inhibition (HI) assays were performed for the determination of antibodies against NDV and AIV and their genotyping and subtyping, respectively. Overall, 47.5% and 67.4% seroprevalence of NDV and AIV, respectively, was observed in both poultry and wild birds. Based on bird's category, layer chickens had the highest seroprevalence of NDV (60.8%, 95% CI: 52.95­68.22, OR: 0.71) followed by backyard poultry (56.8%, 95% CI: 47.92­65.32, OR: 0.82), broilers (52.7%, 95% CI: 46.84­58.64), pigeons (41.3%, 95% CI: 30.53­52.81, OR: 1.59), peafowls (26.1%, 95% CI: 11.09­48.69, OR: 3.16), ducks (23.8%, 95% CI: 12.59­39.8, OR: 3.57), turkeys (16.7%, 95% CI: 4.41­42.27, OR: 5.58), parrots (14.3%, 95% CI: 2.52­43.85, OR: 6.70) and quails (2.3%, 95% CI: 0.2­13.51, OR: 4.8). Comparatively, backyard chickens had the highest seroprevalence of AIV (78.8%, 95% CI: 70.64­85.22, OR: 0.63) followed by ducks (73.8%, 95% CI: 57.68­85.6, OR: 0.83), layers (73.5%, 95% CI: 65.98­79.89, OR: 0.84), pigeons (72.5%, 95% CI: 61.2­81.61, OR: 0.89), broilers (70.1%, 95% CI: 64.44­75.29), turkeys (55.5%, 95% CI: 31.35­77.6, OR: 1.87), peafowls (47.8%, 95% CI: 27.42­68.9, OR: 2.56) and parrots (42.8%, 95% CI: 18.8­70.3, OR: 3.1). Overall, 40.1%, 34.2%, 31.3%, and 25.1% sera were positive for H9 AIV, G­VII NDV, H7 AIV, and G­VI NDV, respectively. The current study revealed a widespread exposure to NDV and AIV in poultry and captive wild birds. Therefore, it is crucial to include captive wild birds in NDV and AIV surveillance programs to further strengthen disease control measures, particularly in endemic regions.

Genomic characterization of velogenic avian orthoavulavirus 1 isolates from poultry workers: Implications to emergence and its zoonotic potential towards public health

Objective: To carry out the genetic characterization and evolutionary analysis of three avian orthoavulavirus 1 (AOAV-1) isolates from poultry workers with respiratory symptoms. Methods: Using Illumina MiSeq, whole-genome sequencing was carried out to assess the evolutionary dynamics of three AOAV-1 isolates. A phylogenetic and comparative analysis of all coding genes was done using bioinformatics tools. Results: Phylogenetic analysis and genetic distance estimation suggested a close relationship among human- and avian-originated velogenic strains of genotype XIII, sub-genotype XIII.2.1. Several substitutions in the significant structural and biological motifs were exclusively identified in the human-originated strains. Conclusions: To our knowledge, this is the first report of a velogenic AOAV-1 isolate from natural infection of the human upper respiratory tract. Our findings highlight the evolution and zoonotic potential of velogenic AOAV-1 in a disease endemic setting.