The incidence of Ross River virus disease in South Australia, 1992 to 2003

Ross River virus (RRV) disease is the most frequently notifi ed arboviral disease in Australia, and the burden of this disease to Australian society is significant. We have studied the incidence of RRV disease between 1992 and 2003 in South Australia. Our findings suggest that the incidence of the disease in South Australia over the study period was relatively stable. There were four epidemics in the study period, with the majority of cases acquired from regions along the River Murray. There was some evidence of spread of the disease to regions in which activity of RRV had not been previously recognised, such as the Mid-North and the South-East. In terms of disease distribution amongst the population, it was found that the highest rates occurred in the 30â 49 year age range. There was no significant difference in disease rates between males and females. In order to facilitate further research into RRV disease transmission, we recommend that the suspected region of acquisition be a mandatory component of the national notifi cation dataset.Christopher M Horwood and Peng B