6 September 2011
Biting midge numbers will be reaching their yearly peak over the coming week, coinciding with September's full moon, according to DoH Director of Medical Entomology, Peter Whelan, who has reminded Top Enders to take precautions against being bitten.
Mr Whelan's advice is to avoid areas where midges breed, especially during the hour on either side of sunrise and sunset.
"If you are in at-risk area, cover up with long-sleeved shirts, long trousers, socks and shoes and apply DEET or picaridin-based repellents. Insecticide coils, mosquito lanterns and insecticide barrier applications are also helpful.
"If you get bitten, soothing lotions may provide relief. Ice packs can be applied to the site of stronger bite reactions, but a severe reaction may require medical attention."
Mangrove biting midges, Culicoides ornatus, are expected to cause problems throughout the NT coast within 1.5 km of extensive areas of coastal mangroves. Peak biting midge activity will occur in the period three days before and three days after the full moon on 12 September when they emerge from their mangrove mud breeding areas.
"The saliva midges inject into their human hosts contains chemicals that cause pain and swelling, particularly for newcomers to the NT.
"The bite area can be extremely itchy. People should avoid scratching the bites because this can easily break the skin, introducing bacterial infections that can lead to unsightly sores.
"Biting midges emerge around the half moon period, but are only a problem around the later full and new moons. Female biting midges don't disperse out of the mangroves until around the two periods of high tides each month, after they have laid their first batch of eggs in their mangrove breeding places.
"Female mangrove midges need a blood meal for their second batch of eggs to mature, and they are actively searching for this after they disperse out of the mangroves."
In the Top End, the greatest numbers of midges are experienced during the late dry season and build up, from August to November, with high numbers around new moons and nearly twice as high around full moons.
Mangrove creek areas and areas in Darwin and Palmerston that will see increased midge activity include:
Moderate:
Ludmilla Creek |
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Moderate to High:
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High to Very High:
· Palmerston rural residential areas within 1 km of harbour-fronting mangroves.
Very High:
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A 2011 calendar detailing expected biting midge periods is available at: http://www.health.nt.gov.au/Medical_Entomology/Insect_Pest_Periods/index.aspx
Media Contact: Robin Osborne 899 92886 or 0488 692 781
