In Australia, Ross River virus (RRV) is predominantly identified and managed through passive health surveillance. Here, the proactive use of environmental datasets to improve community-scale public health interventions in southeastern Tasmania is explored. Known environmental drivers (temperature, rainfall, tide) of the RRV vector Aedes camptorhynchus are analysed against cumulative case records for five adjacent local government areas (LGAs) from 1993 to 2009. Allowing for a 0- to 3-month lag period, temperature was the most significant driver of RRV cases at 1-month lag, contributing to a 23·2% increase in cases above the long-term case average. The potential for RRV to become an emerging public health issue in Tasmania due to projected climate changes is discussed. Moreover, practical outputs from this research are proposed including the development of an early warning system for local councils to implement preventative measures, such as public outreach and mosquito spray programmes.

The Yalgorup lakes, a groundwater-fed system in south-western Australia recognized as a Ramsar wetland, hold significant scientific and conservation value due to the presence of a unique range of lake systems, resident waterfowl and, on the eastern shore of Lake Clifton, the presence of the only thrombolite reef in the southern hemisphere. Recent concern over changing physico-chemical conditions in the lakes, particularly an increase in salinity, prompted this study: the current status of the inherent thrombolite community is unknown. Salinity, total phosphorous (TP), phosphate, total nitrogen (TN), nitrate, chlorophyll-a and relative abundance of the thrombolite microflora were measured in Lake Clifton to analyse changing conditions in this lake and to determine the effect of these water parameters on the thrombolite community. Comparisons with historical data revealed a significant increase in salinity since 1985 and a possible increase in phosphorus concentrations in the lake in the recent decade, although historical nutrient data are rather sparse. The increased salinity may be due to concentration of lake water through a combination of high evaporation, long-term reduction in rainfall and increased groundwater abstraction. Comparison of the composition of the thrombolite community with historical data indicates a large reduction in relative abundance of Scytonema sp. and other filamentous cyanobacterial species, which are believed to be fundamental for the thrombolite structure. It is concluded the changing physico-chemical environment of the Yalgorup Lakes may have led to the decline in important genera in the thrombolite community; however, the mechanisms underlying this change remain unknown.

Relationships of the Ross River virus (Togoviridae: Alphavirus) vector, Aedes camptorhynchus (Thomson) (Diptera: Culicidae), to biotic and abiotic factors in saltmarshes of south-eastern Tasmania, Australia: a preliminary studya en_825 344..355 AbstractComprehending ecological drivers of mosquito (Diptera: Culicidae) abundance involves a broad appreciation of their abiotic and biotic determinants. Such an appreciation is important where mosquito species cause significant nuisance to humans or are vectors of infectious disease. Here, a preliminary investigation is presented of relationships between larval abundance of the Ross River virus (RRV, Togoviridae: Alphavirus) vector Aedes camptorhynchus (Thomson), in saltmarshes of Tasmania, Australia, to environmental variables, aquatic fauna and surrounding land-use. Surveys of water bodies within six saltmarsh areas were undertaken during relatively stable (dry) environmental conditions, and one saltmarsh was opportunistically re-sampled following a heavy rainfall event. This study was intended to create a baseline of information from which to launch future, more detailed and targeted investigations. Significant relationships between land-use, environmental variables and aquatic fauna among water bodies were found. Abundance of Ae. camptorhynchus larvae was relatively low across sites during dry environmental conditions, but larvae were highly abundant in water bodies at one site following heavy rainfall. Abiotic and biotic correlates (potential determinants) with larval Ae. camptorhynchus abundance differed during these two sampling periods. During dry environmental conditions larvae were negatively related to pH, turbidity, dissolved magnesium, presence of decapods and abundance of amphipods, and positively related to samphire cover. Following rainfall, larval abundance was negatively related to abundance of ostracods. Indirect relationships between land-use and abundance of Ae. camptorhynchus may exist, but more detailed investigations are required to explore this implication.

BackgroundEmerging environmental pressures resulting from climate change and globalization challenge the capacity of health information systems (HIS) in the Pacific to inform future policy and public health interventions. Ciguatera, a globally common marine food-borne illness, is used here to illustrate specific HIS challenges in the Pacific and how these might be overcome proactively to meet the changing surveillance needs resulting from environmental change.ObjectivesWe review and highlight inefficiencies in the reactive nature of existing HIS in the Pacific to collect, collate, and communicate ciguatera fish poisoning data currently used to inform public health intervention. Further, we review the capacity of existing HIS to respond to new data needs associated with shifts in ciguatera disease burden likely to result from coral reef habitat disruption.DiscussionImproved knowledge on the ecological drivers of ciguatera prevalence at local and regional levels is needed, combined with enhanced surveillance techniques and data management systems, to capture environmental drivers as well as health outcomes data.ConclusionsThe capacity of public HIS to detect and prevent future outbreaks is largely dependent on the future development of governance strategies that promote proactive surveillance and health action. Accordingly, we present an innovative framework from which to stimulate scientific debate on how this might be achieved by using existing larger scale data sets and multidisciplinary collaborations.

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