The impact of our research
Potentially deadly diseases can be spread when humans are bitten by an infected mosquito – generally from the Aedes aegypti or Aedes albopictus species. Our researchers are working on a variety of mosquito-borne viruses to better control and predict the threat they pose to humans.
Our scientists have helped map the most complete genetic picture of the Aedes aegypti mosquito. Understanding how this mosquito efficiently transmits viruses can accelerate our search for better treatments.
We’ve found that the Wolbachia bacteria prevents mosquitoes from becoming infected with dengue virus. This discovery means we can prevent mosquitoes from transmitting the virus to humans.
Dangerous mosquito-borne viruses are spreading at an alarming rate. To combat this threat, we’re facilitating training workshops for Pacific Island nations and international institutions.
Our state-of-the-art pathogen and insect containment facilities allow us to study mosquito–parasite interactions and test new control measures.
We’re trialling new, highly effective devices that target the mosquitoes that spread dengue, Chikungunya and Zika.
About other mosquito-borne diseases
Mosquito-borne viruses are diseases spread to humans by the bite of an infected mosquito. Some of the most common are dengue, Zika and Chikungunya. These viruses can be transmitted between humans by the mosquitoes Aedes aegypti and Aedes albopictus, mostly in urban environments.
Half the world’s population is at significant risk of being infected with a mosquito-borne virus – four billion people living in more than 130 countries.
Several mosquito-borne viruses can be transmitted in Australia, particularly Ross River fever, Barmah Forest virus, Murray River encephalitis and Japanese encephalitis virus (JEV).
Most mosquito-borne viral diseases don’t have a cure or preventative treatments. Notable exceptions are the vaccines developed against JEV and yellow fever, and the partially effective vaccine available for dengue.
Managing mosquito-borne viral diseases largely relies on controlling mosquito populations and reducing the amount of contact between mosquitoes and humans. These efforts are particularly challenging for zoonotic diseases – they involve many different animal and vector species, making it hard to deploy targeted interventions.
There’s a tremendous need to develop better mosquito control and surveillance tools, identify risky transmission pathways and environments, and search for new vaccines and therapeutants.
Which viruses do we study?
Zika virus is primarily spread by the Aedes aegypti mosquito. 80% of infections are asymptomatic or lead to mild febrile illness in adults.
However, Zika virus can be passed from mothers to embryos in the womb. This can cause devastating developmental and neurological effects for unborn babies, including microcephaly and central nervous malformations.
Zika virus caused an unprecedented epidemic in the Americas in 2016, declared by the WHO as a Public Health Emergency of International Concern. There are currently no vaccines or cures for Zika virus.
Ross River virus (RRV) is a pathogen that circulates widely among marsupials and birds.
It’s transmitted to humans by the Culex annulirostris and Aedes vigilax mosquitoes. These are abundant across Australia and commonly bite animals, birds, and humans.
Symptoms include fever, headache, and pain in muscles and joints. This may be accompanied by a rash. While most people recover within weeks, some will experience debilitating joint pain and fatigue for many months.
The largest Australian Ross River fever epidemic occurred in 2015, with 9,550 reported cases. Most of these were recorded in Queensland, including metropolitan Brisbane.
Barmah Forest virus is the second most reported mosquito-borne virus in Australia.
Its transmission cycles and symptoms are very similar to those of RRV, although symptoms are generally less severe.
The similarity between the Ross River and Barmah Forest viruses often makes them hard to diagnose without a blood test.
Murray Valley encephalitis is another example of an Australian mosquito-borne zoonosis. It’s transmitted by Culex annulirostris mosquitoes.
Most human infections are asymptomatic, and outbreaks are rare. When symptoms do occur, the disease has a very high fatality rate.