Show Notes
️ Episode 93: Neuroinvasive and Pulmonary Virulence of H5N1 Clade 2.3.4.4b Genotype B3.13
In this episode of PaperCast Base by Base, we explore how a bovine-derived H5N1 virus from clade 2.3.4.4b genotype B3.13 exhibits enhanced pulmonary and neurovirulent properties in mouse models, highlighting its potential implications for zoonotic transmission and public health.
Study Highlights:
Using intranasal and orogastric inoculation of C57BL/6J and BALB/c mice with four clade 2.3.4.4b H5N1 isolates, the researchers assessed weight loss, survival, tissue viral loads, histopathology and cytokine responses
The bovine B3.13 isolate caused rapid uniform lethality at low doses and induced severe respiratory disease accompanied by neurologic signs in C57BL/6J mice
High viral titers were observed in lung and brain tissues, supporting systemic spread and neurotropism of the bovine isolate
Histological analyses revealed abundant viral antigen in respiratory and neural cells without overt brain lesions, accompanied by robust pro-inflammatory cytokine profiles in the central nervous system
Comparative analysis showed that the bovine genotype B3.13 strain possessed greater neuroinvasive and neurovirulent capacity than mink, mountain lion and reference human isolates
Conclusion:
These findings underscore the importance of monitoring emergent HPAI H5N1 genotypes in mammals and support the use of these mouse models for evaluating vaccines and therapeutics targeting neuroinvasive influenza strains
Reference:
Tipih T, Mariappan V, Yinda KC, Meade-White K, Lewis M, Okumura A, McCarthy N, Altynova E, Leventhal SS, Bushmaker T, Clancy CS, de Wit E, Munster VJ, Feldmann H & Rosenke K. Highly pathogenic avian influenza H5N1 clade 2.3.4.4b genotype B3.13 is highly virulent for mice, rapidly causing acute pulmonary and neurologic disease. Nat Commun. 2025;16:5738. doi:10.1038/s41467-025-60407-y
License:
This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/