Cairns has a tropical climate with lush rainforests, mangroves and high rainfall, all of which contribute to ideal breeding conditions for mosquitoes and biting midges.
More than 220 mosquito species can be found in Queensland, and many of these are carriers of diseases such as Malaria, Ross River Fever and Dengue Fever. Fortunately, none of these diseases are endemic to this area. However, they can be easily introduced by infected visitors to Tropical North Queensland from countries where the diseases occur.
Vector Control UnitVectors are animals which carry bacteria, parasites, viruses or other micro-organisms that are hazardous to human health. Council's Vector Control Unit works to reduce the numbers of mosquitoes and midges to an acceptable level and to assist in limiting the spread of vector-borne diseases.
The Vector Control Unit's main activities are:
- Proactive chemical spraying in known breeding areas for nuisance mosquito control
- Response to complaints of vector breeding
- Cooperation with Queensland Health in anti-Dengue Fever procedures
- Proactive on-site monitoring procedures to determine breeding sites and vector species
- Development of biological control measures, such as specific fish breeds, to lessen the reliance on chemical means of control of nuisance mosquito larvae
- Maintenance of a Mosquito Chemical Allergy Register.
Nuisance mosquito control
Mosquitoes require water in which to breed. Females lay eggs on the water surface or on water's edge. The eggs hatch into larvae (wrigglers) which live under the water and become pupae (tumblers) which again live under the water, before emerging from the water as an adult, flying mosquito.
Council uses only environmentally friendly chemicals which have been specifically approved for mosquito control. If you do not wish to be exposed to mosquito control chemicals, contact Council's Public Health Unit to have your details recorded in the Mosquito Chemical Allergy Register.
Spraying for the control of adult mosquitoes is conducted prior to 8:00 am in order to minimise any contact between the general public and the chemicals being employed. No chemical treatment occurs within close proximity of those residents listed on the Mosquito Chemical Allergy Register. The control of mosquito larvae and actioning of any complaints is dealt with during 'normal' business hours because of the decreased risk from the agents utilised for this purpose.
Health Services is currently developing a Vector Control Policy which, when implemented, will provide an integrated technology based program based on the latest principles of vector control and employing a wide variety of control measures. These will include:
- Chemical control for adults and larvae
- Biological control through specific fish breeds
Queensland Fisheries has issued a permit to Council for the release into selected waterways of specially bred fish to assist in the control of mosquito larvae. Initial studies have shown that these fish significantly decrease the incidence of mosquito larvae and have contributed to a decrease in the use of chemicals in these areas. Further breeding of different species is underway to widen the potential areas into which fish may be released to combat mosquito larvae.