News & Media Opinion Pieces Ross River Virus in Tasmania: A case study for climate change adaptation

Ross River Virus in Tasmania: A case study for climate change adaptation

On November 20th, Tasmanian DEA Members Dr Frank Nicklason and Rohan Church attended a multidisciplinary workshop as part of a study assessing the risk and vulnerability of the Tasmanian community to Ross River Virus (RRV) infection in a changing climate. 

The study was being lead by Anna Lyth of the University of Tasmania’s School of Geography and Environmental Studies, with input from academics from both climate science and health research backgrounds.  After some preliminary work on vulnerability assessment, the workshop was aimed at engaging various professional communities of practice to further explore the current state of awareness and adaptive capacity potential to respond to increasing risk of RRV in Tasmania. Other workshop participants included environmental health officers from local government, ecologists and those involved in land management and planning work.

One of DEA’s Tasmanian representatives, Rohan Church, has provided this further summary and reflection on the workshop and the broader implications for Tasmania’s response to climate change.


By Rohan Church (DEA Tasmania rep.)

Prior to the workshop, I was initially skeptical of the relevance of RRV to Tasmania – thinking that it was largely a disease of the Australian tropics.  However, I was surprised to learn that the incidence rate of documented RRV cases per capita in Tasmania is actually only marginally less than that in northern Queensland.  Although the infection is highly seasonal and occurring at present only in sporadic epidemics, the burden of disease in Tasmania caused by RRV has not been insignificant, with a notable outbreak of some 170 documented cases in 2002, most of which were in the south-east of the state.  It is thought that many more cases went undiagnosed either due to patients not presenting or not being tested for the disease.  While there has still been seasonal peaks of infection, there has been no further large outbreaks of the disease since 2002.  However, there is now an increasing amount of evidence suggesting that climate change, which is driving increasing temperatures and changing rainfall patterns in Tasmania, will promote mosquito breeding and hence lead to an increased incidence of RRV.

RRV is an arbovirus which is the most common vector borne disease in Australia, being transmitted between human and animal hosts by 3 species of mosquito, of which Aedes Camptorhynchus is the most significant in Tasmania.  In human adults (the disease interestingly does not seem to affect children), RRV causes an acute flu-like illness with a symmetrical polyarthritis and in some cases myalgias, headache and a maculopapular rash.  Whilst RRV is not a fatal condition, the clinical syndrome it causes can be highly debilitating if it develops chronicity, with fatigue and arthralgias lasting months and even years in some cases.

Although RRV can currently be easily diagnosed with a serological assay, with the relatively non-specific presentation of the disease and a perceived relatively low burden of RRV in Tasmania, clinicians presumably do not always investigate this as a possible cause.  Being a self-limiting condition with no available treatment, the clinical value of making a serological diagnosis is clearly arguable.  However, accurate early diagnosis may limit further unnecessary investigations or referrals, and prevent inappropriate treatment from being prescribed.

Perhaps alarmingly, one of the study authors had found that Tasmanian GPs who were skeptical of climate change science were significantly less likely to investigate causes of disease linked to global warming.

Whilst there was undoubtedly some real health issues being presented and discussed at this workshop, Dr Nicklason and others made the point that it seems likely that other impacts of climate change and peak oil were likely to be of much more significance to health in Tasmania than the increased incidence of RRV.  Nonetheless, all participants agreed that this research and its policy outcomes have the potential to serve as an excellent case study in how various sectors of the Tasmanian community can respond at the inidividual and policy level to the impacts of climate change in this state. 

Ultimately however, the greatest way to reduce the risk of RRV in Tasmania would still seem to be mitigating the effects of climate change by urgently taking action to reduce global greenhouse gas emissions.  While this study workshop seemed to be starting an important conversation on integrated policy responses to climate change impacts, it was mildly disheartening to be discussing how to adapt to global warming rather than how to minimise its occurrence.  Nevertheless, while our work on reducing greenhouse gas emissions through reducing fossil fuel usage should remain a top priority, it is also important for DEA as a health advocacy organisation to be mindful of the new health challenges that are arising from climate change that we so far have been unable to prevent. 

We look forward to reading about the final outcomes of this study and its recommendations for policy makers about broader and more generic community responses to climate changes and their associated health impacts.