PARENT SESSION
Tuesday, August 8, 1:30-5:00 pm
COS 41 - Disease ecology II: viruses and epidemics
L-4, Lobby Level, Cook Convention Center
Presiders: K LoGiudice
Dryland salinity and the ecology of Ross River virus.
Carver, Scott*,1, Jardine, Andrew1, Weinstein, Phillip1, Spafford-Jacob, Helen1, Storey, Andrew, 1 University of Western Australia, Perth, WA, Australia
ABSTRACT- Ross River virus (RRv) is a mosquito-borne disease that affects approximately 5000 people in Australia each year, causing fatigue, aching joints and flu-like symptoms. This endemic Australian disease has a complex ecology whose activity is determined by interactions between the environment, vector and mammalian (primarily marsupial) host populations. In the southwest of Western Australia (WA) RRv is principally transmitted by the saltwater breeding species of mosquito Ochlerotatus camptorhynchus. The range of this vector mosquito species is expanding due to dryland salinity (an environmental salinisation of surface soils and water, brought about by agricultural clearing and the resulting rise in groundwater levels and movement of stored salt to the soil surface). As part of a larger project aimed at understanding the effect of dryland salinity on the ecological components of RRv, aquatic invertebrate communities were surveyed across a large area of the WA wheatbelt region. Salinity influenced the composition of mosquito communities, selecting for less diverse populations, dominated by Oc. Camptorhynchus. Salinity also negatively affected other invertebrate families, particularly the overall abundance of invertebrates and the diversity of predator groups. It is clear from these results that dryland salinity disrupts trophic communities causing a cascade that favours the RRv vector Oc. Camptorhynchus. To further our understanding of the influence dryland salinity has on RRv ecology our future interdisciplinary investigations are targeting vertebrate host (including human) communities and the interactions between hosts, vectors and disease transmission.
Key words: Disease ecology, Trophic cascade, Environmental change