The Infectious Bronchitis Coronavirus Pneumonia Model Presenting a Novel Insight for the SARS-CoV-2 Dissemination...

Area of Science:

• Veterinary Virology
• Avian Pathology
• Coronaviridae

Background:

• Infectious bronchitis (IB) in chickens, caused by a Gamma coronavirus, affects the respiratory and reproductive systems.
• IBV pathology in chickens shares similarities with SARS-CoV-2 in humans, particularly respiratory system damage.

Purpose of the Study:

• To evaluate the efficacy of four orally administered virucidal drugs against infectious bronchitis virus (IBV) in chickens.
• To investigate the potential route of IBV infection and spread, hypothesizing intestinal accumulation followed by hematogenous dissemination.

Main Methods:

• Chickens were inoculated with an attenuated IBV vaccine strain (H120).
• Experimental groups received one of four virucidal drugs: Argovit, Triviron, Ecocid, or lauric acid monoglyceride.
• Inflammatory changes and viral genomic RNA in the intestines, lungs, and thymus were assessed on day 6 post-inoculation.

Main Results:

• Control group chickens exhibited inflammatory changes in the intestines, lungs, and thymus.
• Experimental groups showed reduced inflammatory responses and lower proportions of IBV genomic RNA in thymus and lung tissues.
• Virucidal drug activity was primarily observed in the intestine, suggesting localized efficacy.

Conclusions:

• Oral virucidal formulations demonstrated protective effects against IBV infection in chickens, primarily within the intestinal tract.
• The findings support the hypothesis that coronaviruses, including IBV and potentially SARS-CoV-2, may accumulate in the intestine and spread to the lungs via hematogenous redistribution.
• This study provides indirect evidence for a common pathogenesis mechanism among different coronaviruses.