A historical Hawaiian Avipoxvirus genome reconstructed from an 1898 museum specimen

Avipoxvirus is an avian pathogen that likely contributed to the declines and extinctions of endemic Hawaiian birds since its 19th century introduction. We surveyed 719 DNA libraries, including 639 representing 440 Hawaiian bird specimens, for evidence of Avipoxvirus infection. We reconstructed a 5.2× Avipoxvirus genome from an 1898 Hawaii ‘amakihi (Chlorodrepanis virens) specimen. Its sequence matched an extant Hawaiian Avipoxvirus strain, supporting the strain’s persistence in Hawaii over the last century. We identified the earliest molecularly verified case of Avipoxvirus in the Hawaiian Islands in an 1887 ʻalalā (Corvus hawaiiensis) specimen and reconstructed a partial Avipoxvirus genome from this specimen. Both specimens’ Avipoxvirus strains were most closely related to canarypox virus, suggesting that introduced passerines may be the source of Avipoxvirus in Hawaiian endemic land birds. These findings clarify the origins and evolution of Avipoxvirus in Hawaii and provide evidence for the broader role of pathogens in driving biodiversity loss.