Dengue Safe Project
The Dengue Safe Project is a partnership between Townsville Hospital and Health Service, World Mosquito Program and local governments in north Queensland.
The aim is to make Queensland safe from dengue fever and Zika virus.
How we do it
For more than a decade, the World Mosquito Program has worked with Queensland Health to protect the region from mosquito-borne viruses. They use a method to create 'dengue-safe mosquitoes' that cannot spread dengue or Zika.
Entomologists (scientists who study insects) provide dengue-safe mosquito eggs to field teams. These eggs carry common insect bacteria called Wolbachia. The bacteria block the growth of dengue, Zika, and other viruses in mosquitoes. This stops them spreading to diseases between people.
Our field teams work with community volunteers to find places to release the eggs. When they hatch, the mosquitoes carrying Wolbachia pass it to their offspring. Soon almost all mosquitoes will carry the bacteria, stopping them spreading viruses like dengue and Zika and protecting people across the region.
We supply dengue-safe mosquito eggs in buckets and work with the public to release mosquitoes and to track mosquito numbers.
This project has led to a big drop in mosquito-borne disease outbreaks across north Queensland. The technique is being used in 14 countries around the world.
The Wolbachia bacteria are natural and safe for humans and animals. The method does not noticeably change mosquito populations. It also does not use chemicals, genetic changes, or the elimination of mosquito populations.
Our current project
We will focus on the Ayr region for the remainder of 2023 and into 2024.
Successful dengue-safe mosquito releases in Townsville, Charters Towers and Ingham have protected those regions but work is not complete.
With international travel, people can carry dengue fever and other viruses into Australia from abroad. This increases the risk of mosquito-borne outbreaks. If you live in Ayr and want to help, register your interest below.
August - November 2023: Consultation, pre-release, and planning
November 2023 - June 2024: Mosquito release
January - March 2025: Post-release monitoring
Mosquito release containers
Mosquito release containers hold water, dengue-safe mosquito eggs, and a food source for the hatching larvae, which are called wrigglers. These will grow into adult mosquitoes over about one to two weeks.
Field officers check the containers every two weeks to resupply mosquito eggs, food, and to top up water levels. The containers are small (160mm x 140mm) with lids and have Dengue Safe Project branding.
Mosquito monitoring traps
We use chemical-free traps to count and test mosquitoes. The traps (36cm x 40cm) are collapsible fabric containers with holes in the top. They trap nearby mosquitoes and a small electric fan pulls them in. Team members check the traps fortnightly to work out the percentage of mosquitoes carrying Wolbachia.
How Wolbachia works
Volunteer with us
The project’s success relies on volunteers. You can help us reduce the spread of mosquito-borne diseases by either hosting egg containers to hatch our dengue-safe mosquitoes or having mosquito monitoring traps at home to track the project's progress.
Frequently asked questions
What kind of mosquito transmits dengue and Zika virus?
The Aedes aegypti mosquito is the main species which spreads dengue and Zika viruses. It looks like most other mosquitoes. Aedes aegypti live and breed around houses and near humans.
They breed in artificial containers like old tyres, pot plant bases, and any junk which collects water. The female mosquitoes bite people for blood. Mosquitoes which are found indoors and feed during the day are likely Aedes aegypti mosquitoes.
You can find more information about the Aedes Aegypti here.
What is Wolbachia?
Wolbachia are harmless bacteria found in more than 50 per cent of insect species, including some mosquitoes.
It is not regularly found in the main species which spreads dengue and Zika, the Aedes aegypti mosquito.
Research by the World Mosquito Program has shown that Aedes aegypti mosquito strains which carry Wolbachia cannot spread viruses like dengue and Zika.
Find out more about the Wolbachia method here.
How do Wolbachia work?
Put simply, Wolbachia bacteria make it hard for dengue or Zika to survive in a mosquito. If a mosquito cannot grow a virus, then it cannot spread it to people.
Mosquitoes carrying Wolbachia eventually take over in areas where enough are released.
Is Wolbachia safe?
The Wolbachia bacteria are safe for humans, animals, and nature.
Years of research has not found a risk linked to releasing Wolbachia carrying mosquitoes.
You can find out more here.
Will the bite of a mosquito with Wolbachia hurt more than a normal bite?
No, the Wolbachia bacteria occur naturally inside insects and are safe for humans. They do not enter people or change the way a mosquito bites.
Do other animals carry Wolbachia?
Wolbachia bacteria are found in spiders, insects, and other small creatures.
More than 50 per cent of insect species like butterflies, dragonflies, moths, and some mosquitoes carry it.
Wolbachia are not found in any larger animals like mammals, reptiles, birds, or fish.
What type of Wolbachia do we work with?
Wolbachia is the name for a species of bacteria. There are many different types and strains of the bacteria.
The wMel strain of the bacteria has been introduced to wild mosquitoes to reduce the spread of viruses like dengue and Zika.
How is Wolbachia transferred between mosquitoes?
Wolbachia are passed down from a parent mosquito inside the egg.
When a male mosquito carrying the bacteria mates with a female without the bacteria, that female’s eggs do not hatch.
Eggs from female mosquitoes carrying Wolbachia hatch normally and are born carrying Wolbachia.
Over time the numbers of males and female mosquitoes with Wolbachia will grow.
Townsville Public Health Unit Dengue Safe Project:
Phone: (07) 4433 6900
Fax: (07) 4433 6901
Senior medical entomologist and project manager:
Senior vector control officer and project lead: