Molecular characterization of variant infectious bronchitis virus in China, 2019: Implications for control programmes

Abstract

Infectious bronchitis virus (IBV), an ongoing emergence enveloped virus with a singlestranded positive-sense RNA genome, belongs to the Gammacoronavirus genus in the Coronaviridae family. IBV-associated tracheitis, nephritis, salpingitis, proventriculitis and egg drop have caused devastating economic losses to poultry industry worldwide. Since the end of 2018, a remarkably increasing number of commercial broilers and layers, vaccinated or not, were infected with IBV in China. Here, we described two IB outbreaks with severe respiratory system or kidney injury in IBV-vaccinated commercial poultry farms in central China. Other possible causative viral pathogens, including avian influenza virus (AIV), Newcastle disease virus (NDV) and Kedah fatal kidney syndrome virus (KFKSV), were excluded by reverse transcription-polymerase chain reaction (RT-PCR), and three virulent IBV strains, HeN-1/China/2019, HeN-2/ China/2019 and HeN-101/China/2019, were identified. Although the gross pathologic appearance of these two IB outbreaks was different, the newly identified IBV strains were all closely related to the ck/China/I0529/17 strain and grouped into GI-19 genotype clade based on the sequencing and phylogenetic analysis of the complete S1 genes. Moreover, there are still some evolutionary distance between the newly identified IBV strains, HeN-101/China/2019 in particular, and other GI-19 strains, suggesting that Chinese IBV strains constantly emerge and evolve towards different directions. In conclusion, this study provided an insight of the recently emerging IBV outbreaks in IBV-vaccinated commercial poultry farms and identified the genetic characteristics of three virulent GI-19 IBV strains, which shows the need to carry out proper preventive measures and control strategies.

Animal coronaviruses and coronavirus disease 2019: Lesson for One Health approach

“…SARS-CoV-2 has the ability to cross the species barrier, which makes it possible to infect humans, whereas COVID-19-positive humans facilitate the reverse zoonotic transmission of the virus from human to animals (Fig. 1) (Parry, 2020;Zhang et al, 2020b). Among the reported animals, an infected dog did not show any clinical signs, unlike cats.…”

“…Other CoVs from the deltacoronavirus genus include Bulbul coronavirus HKU11, Wigeon coronavirus HKU20, White-eye coronavirus HKU16, Common moorhen coronavirus HKU21, Munia coronavirus HKU13, and Night-heron coronavirus HKU19 that can severely infect birds with more complications (Paim et al, 2019). Even though there were different attempts for effective vaccine development against the CoVs, the rapid mutations and antigenic variations created a hindrance to successfully trigger the local immune response and cure infections (Saif, 2020;Zhang et al, 2020b). Viruses from alphacoronavirus, betacoronavirus, and deltacoronavirus affect the porcine population.…”

The emergence, evolution and spread of infectious bronchitis virus genotype GI-23

“…The new IBV strain sequences isolated in 2018 from Lebanon were made available in the GenBank database, and our analysis based on these sequences confirmed their clustering with the GI-23 strain. In addition, recently released Syrian IBV strain HVR3 sequences have been determined to belong to the GI-23 [22,126,127] genotype. However, no associated publications have been found in either country (Table 3).…”

A comprehensive review of SARS-CoV-2 genetic mutations and lessons from animal coronavirus recombination in one health perspective

“…BCoV also has a wide host range, including dogs, poultry, and giraffes. Genomic analysis revealed that BCoV shows only 49.2-49.3% gene similarity to SARS-CoV-2 (Zhang et al, 2020a).…”