Infectious Bronchitis: Molecular Detection and Characterization in Live Bird Markets in Jos, Plateau State, Nigeria

Abstract

Infectious bronchitis virus (IBV), the avian coronavirus, is a highly contagious coronavirus of birds. It mostly affects the respiratory, urinary and reproductive tract, leading to considerable economic losses to the poultry industry as a result of drop in egg production, undesirable egg quality and poor weight gain. Thus, this study aimed to detect and characterize the virus in live bird markets (LBMs) in Plateau State, Nigeria. One hundred pooled of cloacal and tracheal swab samples each were collected from two LBMs in Jos. Viral RNA was extracted and screened for IBV using real-time RT-PCR. Subsequently, hyper-variable region of the spike (S1) gene of positive samples were amplified and sequenced. IBV nucleic acid was detected in 42% (42/100) of the pooled samples. Phylogenetic analysis of the resulting sequences of S1 gene showed that IBV detected in this study were diversified into two distinct genotypes: GI-14, and GI-23. These genotypes were closely related to a Poland strain with over 95% nucleotide identity, forming a common cluster within the GI-23 group. One isolate showed a notable relationship with a previously reported Nigerian isolate, sharing 85% nucleotide identity, and formed a common cluster within the GI-14 group. Overall, this study established the widespread of IBV and therefore recommends continuous surveillance to identify the current circulating strain for possible local vaccine development for effective control measures to mitigate the spread of the virus in the study area and the country at large.