# An overview of HPAI H5N1 clade 2.3.4.4b and its emerging threat in mainland Australia: Identified knowledge gaps

## TL;DR

This paper reviews the HPAI H5N1 virus clade 2.3.4.4b and its growing threat to mainland Australia, highlighting key knowledge gaps.

## Contribution

The paper identifies critical knowledge gaps in understanding the H5N1 clade 2.3.4.4b's threat to Australia.

## Key findings

- HPAI H5N1 clade 2.3.4.4b is causing a global avian flu outbreak.
- The virus has been detected in Antarctica and on Heard Island, raising concerns for mainland Australia.
- Rapid mutations and changing epidemiology complicate preparedness efforts.

## Abstract

The highly pathogenic avian influenza (HPAI) H5N1 virus, particularly clade 2.3.4.4b, is currently causing a panzootic. The threat of its incursion into mainland Australia is escalating, especially following its detection in Antarctica and recently on Australia's sub-Antarctic territory, Heard Island. Comprehensive research on this emerging risk remains limited, partly due to ongoing rapid genomic mutations and evolving epidemiological dynamics. This review provides an in-depth analysis of clade 2.3.4.4b H5N1 and highlights critical knowledge gaps that must be addressed to mitigate the potential threat to mainland Australia.