DESTINATIONS - OUTDOORS HEALTH & SAFETY
There’s no such place as paradise. No matter how idyllic the location, there’s always something around to stuff it up.
Up north, the most common stuffer-up is the almost invisible insect known as the sandfly. This little biting bastard is actually not a true sandfly; it’s actually a biting midge of the genus Ceratopogonidae.
This nuisance fly inhabits beaches, coastal lagoons, estuaries, mangrove swamps and tidal flats. The biting midge is active mainly at dawn and dusk, in calm weather, and usually not far from water.
The number of midges hatching from pupae and then moving to feed is related to the lunar cycle.
Hatching increases rapidly around the neap tide and females disperse to feed on blood two days before the spring tide. The feeding numbers peak on the day of the spring tide and there are even more when there’s a full moon or a new moon. The peak breeding season is August to October. The female biting midge bites exposed skin, then injects saliva into the pool of blood in the hole, to thin the blood, which is then sucked out to fertilise her eggs. It is the saliva which causes the allergic reaction and itching.
Biting midges have the greatest impact on visitors to an area: ‘locals’ seem to build up some immunity to the biting. In some sensitive people, midges can produce persistent reactions that blister and weep serum from the site of each bite and these reactions may last for several days to weeks.
There is some good news, because although some sandfly species transmit nasty diseases to humans that has not been recorded in Australia.
There are no known, proved methods of permanently controlling biting midges, although there are literally hundreds of theories
on the topic.
Avoidance of biting midge areas is obviously the best method, but personal protection will help in reducing exposure. Long sleeved shirts, long pants and socks should be worn, with a repellent on all exposed skin and hair.
Midges are attracted to bright lights and dark, rather than light-coloured clothing.
The search for the perfect biting midge repellent is ongoing, but scientific studies done by various testing authorities indicate the most effective repellents are those containing Deet (di-ethyl toluamide) or Picaridin. The Defence Forces use Permethrin or Bifenthrin impregnated clothes combined with repellent
on the skin.
Research in Canada and the USA indicates that the Deet content of a repellent lotion increases the protection level, up to concentrations of around 40 percent.
The newest product to be evaluated as a sandfly repellent is a chemical known as MR-08 (menthol propyleneglycol carbonate). MR-08 is a GRAS (generally recognised as safe) chemical that is modified from naturally occurring menthol and used in the food and cosmetic industry today as a ‘cooling’ agent, typically producing the menthol taste in toothpaste.
US-based Poseidon Sciences tested MR-08 against a repellent containing 20 percent Deet. On human volunteers the Deet lotion provided less than 10 minutes protection from bites. When MR-08 was used in the same lotion, the protection time – the time gap between application and the first confirmed bite – was extended to more than 200 minutes.
In Australia you can’t go far north before coming across recipes for midge repellent. Most of these are a cocktail of vegetable or mineral oil, mixed with other substances, including Dettol, vinegar and alcohols. The proponents of these cocktails swear by their effectiveness, but scientific testing has shown them to be of little value. It’s possible that the repellent effect comes down to an oil-coated midge being more concerned about escaping than
Vitamin B ‘dosing’ before entering biting midge areas is another repellent theory that hasn’t worked in scientific testing.
You may need to experiment with different repellents, because what works for one person may not work for the next. Whatever you use, apply it before you get bitten.
The average reaction on midge bite victims is a small red spot which develops into a domed blister with a hole at the top. More sensitive people can develop a red swelling over a few centimetres.
Reactions usually last three or four days and then slowly subside. Soothing lotions such as Eurax and Stingose may give some relief from bites and help prevent secondary infection. Tea tree, eucalyptus oil and Aloe Vera gel can be useful too. More severe reactions require anti-histamine treatment, such as Telfast.
The main danger in tropical areas is scratching the bites and thereby allowing secondary infection to take hold.
We’re always on the lookout for treatments that work effectively on insect bites, even though we use personal insect repellent, we get bitten sometimes.
A while back we discovered a pocket-sized device called the Bite Away – it was claimed to provide instant relief from insect bites and stings, so we tested it over a few months on mosquito bites and midge bites and it actually does as it says. It’s the first thing we reach for now and wouldn’t be without it.
You can purchase the Bite Away directly through Outback Travel Australia, contact us if you’d like to buy one. RRP is $59.95 including postage
A few years ago on a trip to Cape York we evaluated a ‘bite zapper’ that we expected to be nigh on useless. We were quite wrong. The little ‘Mosquito Click’ zapper uses piezoelectricity (the generation of electrical current by the compression or expansion of a quartz crystal).
The makers claim is that reactions such as itches, burns, pains and swelling are reduced in minutes by the reduction or inhibition of histamine in the affected tissue.
A few of us showed typical midge bite lumps after a couple of beachfront days and the (Intelligent Health systems) Mosquito Click proved very effective in reducing swelling and itching.