A report by a team of the University of Western Australia’s researchers warns the rate of mosquito-borne diseases such as Ross River virus will continue to rise unless more careful land clearing practices are adopted.
The report, which highlights the link between deforestation and mosquito-borne disease patterns, was published in the prestigious international science journal BioScience.
In the article researchers Andrew Jardine, Dr Angus Cook and Professor Philip Weinstein, from UWA’s School of Population Health, and Dr Lara O’Sullivan, from UWA’s School of Humanities, cited a report by the Food and Agriculture Organization of the United Nations in 2005.
The FAO report found that from 2000 to 2005 approximately 13 million hectares of forest were cleared each year, a net loss – after reafforestation and forest expansion – of 7.3 million hectares per annum.
"The severity of the impact of such large-scale environmental change on human health is only beginning to be quantified, yet the nexus between such change and human health may be traceable back to antiquity. Are humans slow learners about disease and environmental change?" the researchers ask. "The evidence from the capital of the Roman Empire suggests that perhaps we are."
In the report, Ancient Rome is used as an historical case study of the possible links between deforestation and an increase in malarial disease and Professor Weinstein said there were many examples from around the world that suggested the experiences of Ancient Rome were being repeated.
"A growing body of research, spanning studies from Africa, Australia, and the Amazon, points to a connection between mosquito-borne disease rates and ecological changes associated with deforestation," he said.
"The evidence calls for careful management of agricultural clearing and a multidisciplinary approach to policy development on the issue, particularly in regions where there are already indications of escalating disease rates."
The study cites the impact of land clearing in Western Australia, where deforestation for agriculture has left more than one million hectares of the South West affected by waterlogging and dryland salinity.
"Land clearing in this region has had a pronounced impact on the water balance, as the shallow-rooted annual pasture crops use less water than the deep-rooted native perennial vegetation they replace," it says.
"The resulting increase in recharge and runoff leads to a rise in the water table, thereby bringing saline water to the surface, where halophilic vectors of Ross River virus (mosquitoes) can exploit these new habitats."
(Source: BioScience : University of Western Australia : September 2008)