The year’s biggest tide of 7.75 metres on 10 October has led to an increase of salt marsh mosquitoes in the Darwin region.
The Department of Health is warning residents to take precautions to protect themselves from bites, with mosquitoes expected to remain in large numbers until the end of the week.
“Each year we expect large numbers of these mosquitoes in connection with big tides, and we respond with a range of survey and control operations,” Director of Medical Entomology, Nina Kurucz said.
“We have carried out intensive aerial mosquito survey and control operations in the Leanyer, Holmes Jungle, Micket Creek and Shoal Bay swamps, with a total of 94ha sprayed. Ground mosquito survey and control was also carried out in Darwin urban areas.
“Despite our best efforts, it’s a reality that from time to time mosquito numbers will be high. This is because we have huge areas of brackish swamps and tidal waterways where these mosquitoes breed, coupled with the fact that this variety can travel vast distances outside of our control zones.
“People need to understand that salt marsh mosquitoes can carry the Ross River and Barmah Forest viruses. The current dry conditions are not optimal for disease transmission, but once the humidity increases these mosquitoes will live long enough to transmit those viruses to humans.”
People infected with Ross River or Barmah Forest virus may develop a wide range of symptoms, the most common of which are:
- painful or swollen joints (particularly in the hands, ankles and knees)
- sore muscles
- aching tendons
- skin rash
- fatigue
- fever
- headache
- swollen lymph nodes
Symptoms generally last for a few weeks or months, though in some cases they can linger for up to 12 months.
To protect themselves from being bitten, people in the Top End are advised to:
- avoid locations near coastal swamps and mangrove areas
- avoid outdoor exposure around dusk and at night near areas of dense vegetation and other areas of high mosquito activity
- reduce outdoor activity in the evening and at night if mosquitoes are present
- use mosquito-proof accommodation and camping facilities at night
- wear light coloured clothing with long sleeves, long trousers and socks between dusk and dawn in areas where mosquito bites are likely
- use a protective repellent containing 20 per cent DEET or Picaridin as a supplement to protective clothing when outdoors in areas of mosquito activity. Gels and lotions are the most effective and long-lasting formulations.
- use mosquito coils, mosquito lanterns, and barrier sprays containing bifenthrin in patio and outdoor areas near houses
- ensure children and animals are adequately protected against mosquito bites