Predicting The Future Spread Of Infectious-Disease Vectors
As global warming raises concerns about potential spread of infectious diseases, a team of researchers has demonstrated a way to predict the expanding range of human disease vectors in a changing world.
Researchers from Australia and the University of Wisconsin-Madison have identified the key biological and environmental factors constraining a population of the dengue fever vector, the mosquito Aedes aegypti.
They report that climate changes in Australia during the next 40 years and the insect's ability to adapt to new conditions may allow the mosquitoes to expand into several populated regions of the continent, increasing the risk of disease transmission.
While the current study focuses on the Australian population of the dengue mosquito, these mosquitoes live around the world and present a global threat similar in scope to malaria, according to the Centers for Disease Control and Prevention. Because of the importance of watery breeding sites, the scientists focused on how well the insect's eggs withstand desiccation during dry periods.
By applying a model of rates of evolutionary change, they found that if the mosquitoes' eggs develop an increased resistance to drying out - a trait that has evolved in related insects - the species could spread into larger areas of the continent.