Diversity, origins and virulence of Avipoxviruses in Hawaiian forest birds

Author:

Jarvi, Susan I., Triglia, Dennis, Giannoulis, Alexis, Farias, Margaret E. M., Bianchi, Kiara, Atkinson, Carter T.

Title:

Diversity, origins and virulence of Avipoxviruses in Hawaiian forest birds

Periodical:

Conservation Genetics

Year:

2008

Volume:

9

Pages:

339-348

Subject:

Avian malaria Birds diseases Pathogenicity

Summary:

A primary contributing factor to population declines, extinctions, and changes in the geographic and altitudinal distribution of native forest birds in the Hawaiian archipelago, is a mosquito vector, (Culex quinquefasciatus), and two avian pathogens -- avian malaria, (Plasmodium relictum), and avian pox (Avipoxvirus). However, the role that the avian pox virus has played in the demise of the Hawaiian avifauna, independent of avian malaria, has been difficult to determine from field observations. This is because both the avian malaria and the pox virus occur together more frequently than expected by chance and demographic studies have not accounted for this possible interaction. This introduced avian disease system in Hawaii is an exceptional natural system in which to investigate mixed infections that involve multi-host pathogens and evolution of virulence. Previous studies have indicated that through mixed infections, even avirulent pathogens can play a significant role in influencing the outcome of coupled host-pathogen systems. These results, when considered with theoretical predictions, suggest that mixed infections could significantly contribute to the uncertainty in host-pathogen dynamics with direct implications for host demographics, disease management strategies, and the evolution of virulence. As a result, this study describes host range, geographic range, and genetic diversity of field isolates of avian pox from four main Hawaiian islands -- Hawaii, Maui, Molokai, and Oahu. A genetic documentation is provided of one isolate that was taken from a museum specimen from the beginning of the 20th century. Preliminary evidence for possible differences in the virulence of two genetically distinct isolates in experimentally infected Hawaii Amakihi, (Hamignathus virens), is provided.

Label:

Birds - General

Date:

2008

Collection:

Periodicals