Tag Archives: dengue fever

Love Hertz

James Cook University researchers have found sex sells when it comes to luring male mosquitoes.

Senior Research Officer Brian Johnson and Professor Scott Ritchie set out to make a cheap and effective audio lure for scientists collecting male Aedes aegypti mosquitoes – the species that carries dengue and yellow fever.

They found a tone of precisely 484 Hertz, the frequency of a female Aedes aegypti’s wings, brought 95% of male mosquitoes to the trap.

Johnson says the device cost around $20 and could be run by itself for weeks. “We started with a cheap mobile phone and moved to an even cheaper MP3 player. There are no harmonics, it’s a pure tone and very simple to produce.”

Love Hertz

The effectiveness of the audio lure is easy to see: when it’s switched on, mosquitoes flock to the device, and fly away as soon as it’s turned off, as can be seen in the video.

The invention of the audio trap is timely: male mosquitoes do not bite, but new anti-mosquito strategies involve capturing and sterilising them before releasing them to breed unsuccessfully with females.

“There are a number of projects underway,” says Johnson. “They required capturing and releasing tens of thousands of male mosquitoes, but most traps are aimed at capturing females.”


He says there was no chance of eliminating mosquito populations by trapping males alone, as only a few needed to survive to continue the breeding cycle.

The scientists also found that female mosquitoes were completely oblivious to the sound of male wing beats. “There’s no real need for females to respond to male overtures,” says Johnson.

The team is now optimising the trap for field use and coordinating with trap manufacturers to add the feature to their products.

This article was first published by James Cook University on 6 January 2016. Read the original article here.

Dengue research gets Grand Challenges Explorations grant

The University of Queensland announced today that it is a Grand Challenges Explorations winner, an initiative funded by the Bill & Melinda Gates Foundation. Research groups led by Professor Paul Young of the School of Chemistry and Molecular Biosciences, and Professor Matt Cooper at UQ’s Institute for Molecular Bioscience will pursue an innovative global health and development research project, titled Next-gen diagnostics for field-based surveillance of Wolbachia and arboviral infections in wild mosquitoes.

Grand Challenges Explorations (GCE) funds individuals worldwide to explore ideas that can break the mould in how we solve persistent global health and development challenges. Young and Cooper’s project is one of more than 50 Grand Challenges Explorations Round 15 grants announced today by the Bill & Melinda Gates Foundation.

To receive funding, Young and Cooper and other Grand Challenges Explorations winners demonstrated in a two-page online application a bold idea in one of five critical global heath and development topic areas. The foundation will be accepting applications for the next GCE round in March 2016.

The project aims to develop a portable tool to detect mosquitoes carrying dengue fever. Dengue virus is estimated to infect up to 400 million people globally each year. The next-generation diagnostic tool, which can be used in a field setting, uses quantum dot nanoparticles in a simple, cheap assay to measure the presence of a dengue virus protein. The test is also able to detect Wolbachia carrying mosquitoes. Wolbachia is a naturally occuring bacterium that has been added to mosquitoes to reduce their susceptibility to dengue and other viruses. “The idea is to test mosquitoes in the field for the presence of dengue as an early warning surveillance system,” Young says.

“We need to get the best tests we have out of the lab and into the field, where they can help identify dengue and track prevention measures in real time.  Identifying hot spots early could help us get on top of epidemics before they break out,” says Cooper.

UQ Alumnus Dr Joanne Macdonald of the University of the Sunshine Coast is also a Global Challenges Exploration winner, and will pursue a project entitled: A rapid field test for detecting infected mosquitoes.  Project team members include her former supervisor Professor Roy Hall of UQ’s School of Chemistry and Molecular Biosciences. Macdonald has developed a simple diagnostic test able to detect multiple pathogens that reduces costs compared to performing individual assays, and does not require specialised equipment.

About Grand Challenges Explorations

Grand Challenges Explorations is a US$100 million initiative funded by the Bill & Melinda Gates Foundation. Launched in 2008, over 1160 projects in more than 60 countries have received Grand Challenges Explorations grants. The grant program is open to anyone from any discipline and from any organisation. The initiative uses an agile, accelerated grant-making process with short two-page online applications and no preliminary data required. Initial grants of US$100,000 are awarded two times a year. Successful projects have the opportunity to receive a follow-on grant of up to US$1 million.

The University of Queensland

The University of Queensland (UQ) is one of Australia’s leading research and teaching institutions, ranked in the world’s top 50 by the QS World University Rankings and the Performance Ranking of Scientific Papers for World Universities. The University is the oldest and largest in Queensland, with 50,000-plus students engaged in more than 400 degree programs. UQ has been educating people to create change for a better world for more than a century, producing more than 225,000 graduates since opening in 1911, including more than 11,500 PhDs, a Nobel laureate, the CEO of a Fortune 500 company and leaders in government, law, science, public service and the arts.

This article was first published by the University of Queensland on 13 November 2015. Read the original article here.