The level o protection conferred by commercial vaccines against the new variant Nebraska 95 isolate was evaluated. Complete protection was observed when the IBV Arkansas vaccine was given and when the Massachusetts-Connecticut vaccine was given at 1 and at 1 and 10 days of age. However, partial protection was observed when the Massachusetts-Connecticut vaccine was given only at 10 days of age. ...

Avian infectious bronchitis virus (IBV), which causes respiratory disease in infected birds, belongs to coronavirus group 3. IBV encodes 15 nonstructural proteins (nsp2-nsp16) which play crucial roles in RNA transcription and genome replication. Nonstructural protein 9 (nsp9) has been identified as a protein that is essential to viral replication because of its single-stranded RNA-binding abili...

Influenza B virus (IBV) contributes to substantial influenza-mediated morbidity and mortality, particularly among children. Similar influenza A viruses (IAV), the hemagglutinin (HA) neuraminidase (NA) of IBV undergo antigenic drift, necessitating regular reformulation seasonal vaccines. NA inhibitors, such as oseltamivir, have reduced activity clinical efficacy against IBV, while M2 channel inh...

Background: Avian infectious bronchitis (IB), with avianinfectious bronchitis virus (IBV) as the causing agent, is a ubiquitous endemicdisease of the chicken with devastating effects on its industry. A viralmembrane surface protein called S  notonly induces neutralizing antibodies but also plays an important role in virusbinding and entry to host cells. Technically, S1 protein gene sequencing a...

In this experimental study, our objective was to investigate the macroscopic, microscopic and immunohistochemical findings developed in respiratory system due co-infection with infectious bronchitis virus (IBV) M-41 commensal Bordetella avium tract 15-day-old female Brown-Nick chicks. a total of 70 non-SPF, healthy chicks were randomized into 4 groups. The Group 1 (n=20) infected only IBV-M41 s...

In order to investigate the prevalence and track the genetic evolutions of the circulated infectious bronchitis virus (IBV) strains and their prevalence in Assiut, Egypt, partial S1 gene amplification and sequencing were done during 2013-2014. Three infectious bronchitis virus (IBV) strains with the following accession numbers (KR003438, KR003439 and KR003440 respectively) were detected from 21...

Amino acid sequences of 2 giant non-structural polyproteins (F1 and F2) of infectious bronchitis virus (IBV), a member of Coronaviridae, were compared, by computer-assisted methods, to sequences of a number of other positive strand RNA viral and cellular proteins. By this approach, juxtaposed putative RNA-dependent RNA polymerase, nucleic acid binding ("finger"-like) and RNA helicase domains we...

Six overlapping viral RNAs are synthesized in cells infected with the avian coronavirus infectious bronchitis virus (IBV). These RNAs contain a 3'-coterminal nested sequence set and were assumed to be viral mRNAs. The seven major IBV virion proteins are all produced by processing of three polypeptides of ca. 23, 51, and 115 kilodaltons. These are the core polypeptides of the small membrane prot...

Infectious bronchitis virus (IBV) causes highly contagious respiratory or urogenital tract diseases in chickens. The Maryland 27(Md27) strain was first isolated in 1976 from diseased chicken flocks in the Delmarva Peninsula region. To understand the genetic diversity and phylogenetic relationship of existing strains with Md27, the complete nucleotide sequence of the 3'end coding region (∼7.2 kb...