Faculty of Science, Engineering and Built Environment
School of Life and Environmental Sciences
Discerning the cause of fowl plague outbreaks: drought-rainfall cycles, waterfowl population dynamics, and avian influenza prevalence in Australian avifauna
Participants: Prof Marcel Klaassen (PI), Dr BriAnne Addison and Prof William W Buttemer (CIE), Dr Paul Selleck (AAHL)
Aims and background: Climatic conditions in Australia are erratic and characterised by periods of intense rainfall followed by periods of protracted drought. This has considerable impact on the population dynamics and ecology of many Australian species of waterfowl, which are thought to form a reservoir of avian influenza viruses (AIV). During the wet, waterfowl numbers increase with many serologically naive juveniles entering the population. During the subsequent period of drought, bird densities increase in the few remaining wetlands. We hypothesise that it is during this period of increasing densities of naive birds that AIV prevalence within the population increases dramatically. There is a remarkable coincidence between outbreaks of AIV in Australian poultry farms and the periods of drought following a very wet period. Accordingly, we suspect there is a link between increased risk in AIV outbreaks in poultry farms and our hypothesised increase in AIV prevalence in waterfowl. We further hypothesise that, rather than direct contact between waterfowl and poultry, intermittent avian hosts may be responsible for the transmission of AIV between waterfowl and poultry.
Under the assumption that waterfowl form the prime host of AIV, we aim to conduct a longitudinal study on the prevalence of AIV and AIV-antibodies in a number of waterfowl species. In addition, we will sample a number of other species that live in close proximity to these waterfowl species, which may potentially serve as intermittent hosts between poultry and waterfowl. These data will be used to construct an environmentally driven epidemiological model for AIV prevalence in wildfowl.
Scientific significance and innovation: Australian perspectives on AIV host-pathogen interactions could, in conjunction with findings in the northern hemisphere, help shape global understanding of AIV and other diseases in wildlife. AIV prevalence in the northern hemisphere seems to be highest during autumn migration when many young and serologically naive birds aggregate. The Australian context offers the possibility to elucidate the underlying mechanism for these AIV prevalence dynamics. To this end, we will apply a novel, holistic approach targeting an entire bird community in a dynamic environment, combining both AIV prevalence and sero-prevalence methods at a monthly resolution.
Potential national benefit and strategic alignment with the aims of the CIE: There are notable differences in the biology and ecology of many Australian birds compared to Northern Hemisphere species, in which most research on (AIV) has been conducted. By studying the interactions between a pathogenic microorganism and its host in a dynamic environment the proposed research addresses the CIE's core research topic of "how life reacts to change", bundling the expertise of a range of CIE members integrating traditionally disparate fields of research. Furthermore, this study will inform mitigation strategies directed at avoiding outbreaks of AIV in poultry.
