Microbiology ‐ Infectious Bronchitis Virus (IBV)

The Infectious Bronchitis Virus is a coronavirus in the order Nidovirales. Coronaviruses have an envelope surrounding an RNA genome and are divided into 3 main groups designated alpha, beta and gamma. IBV is a gamma coronavirus.

Electron micrograph of Infectious Bronchitis virus particles Cook, J.K.A. (1983). Isolation of a new serotype of infectious bronchitis‐like virus from chickens in England. Veterinary Record, 112, 104‐105.

Properties

• Pleomorphic, but mostly rounded, "enveloped" virus with spikes on its surface.
• Contains a single stranded, positive sense RNA genome (see below) and codes for the viral polymerase (Replicase 1a/1ab), and structural proteins spike, envelope, membrane and nucleocapsid.
• Family: Coronaviridae.
• Rather fragile virus, infectivity of the virus is easily lost emphasizing the need to properly handle live vaccines.
• Able to withstand pH ranges of pH 2 ‐ 12 depending on the strain, temperature and time of exposure.
• Inactivated after 15 minutes at 56°C and after 90 minutes at 45°C.
• Sensitive to most common disinfectants.