Australasian Science: Australia's authority on science since 1938

Mozzie Mash Detects Dengue

By Stephen Luntz

A cocktail of mashed-up mosquitoes could be the new tool in the fight against dengue fever.

Dengue fever is spread by Aedes aegypti and three closely related mosquito species. As with malaria, attempts to wipe mosquito populations out entirely are likely to fail, with resistance developing to any mass elimination method. More targeted attacks on dengue-carrying populations may have more success, but these have been hampered by a lack of detection mechanisms.

Dr David Muller of the University of Queensland has produced a process that requires neither expensive equipment nor highly trained workers. It involves catching a stock of mosquitoes, mashing them up and adding them to a biotesting tube. Chemicals in the tube will produce a red line if as few as one mosquito in 100 is carrying dengue.

Muller says his work, published in the Journal of Virological Methods, “will be viable for use in developing regions of the world where dengue is a significant health and economic burden.”

“The goal of this work is to provide the tools to not only assess mosquito numbers in the field but also their infection status,” says Muller’s team leader, Prof Paul Young. “This information could then be directly uploaded with

GPS information via mobile devices to coordinating centres.”

While dengue is endemic to some areas, causing almost a million hospitalisations per year, outbreaks are more sporadic in places such as Far North Queensland. Detection could allow for targeted spraying, or the use of insecticide-impregnated mosquito nets.

More than 100 million people are infected with dengue each year, which has no vaccine or treatment other than fluid replacement and pain relief. While infection against one strain of the dengue virus provides lifelong protection against that strain, only short-term immunity is offered against the other three strains. As this immunity falls, infection with a different strain can be fatal.