By Laurie Sullivan
You might recall that I recently confessed to being the go-to guy for marauding mozzies at barbeques. Well, it’s time to admit that they also love me in bed, so to speak.
Once the buzzing in my ear has woken me, I can’t sleep until the tiny intruder has been dispatched. A shower of bug spray makes for a lingering death, but my preferred method is a more satisfying slap with slipper or thong delivered with extreme prejudice. Splat… take that!
Which is fine for the odd lone mozzie that sneaks into your bedroom.
But, what do you do when you’re travelling in the tropics and the mozzies are big, ferocious, at squadron strength, and possibly carrying diseases like malaria, dengue, or Chikungunya? Especially if the insect screens at your less-than-5-star digs have seen better days or are simply absent?
In the tropics, we are talking serious mozzies. The females are relentless and will spend hours searching for a chance to get a feed of your blood, the protein ‘hit’ they need to lay their eggs.
BYO and stay off the midnight menu
The answer is a bed net. A net is not only effective against disease-carrying mozzies, but any nasties intent on making a meal of you, like ticks, beetles, flies, sand flies, and spiders.
But, beware. The nets provided for guests in hostels and other budget accommodation in much of the developing world often come with holes literally a foot wide. (Of course, you only discover these when you unfurl the net at bedtime, befuddled by a belly full of Bintang or Tiger!)
The solution? Bring your own.
So, what should you look for in a mozzie net?
What to look for in a travel bed net
Colour: Nets are available in various colours (I’ve seen blue and green, along with white). White is best: it’s easier to see lurking bugs against a white background.
Shape: A rectangular-shaped net can be tucked under the mattress more easily and there’s less chance of your arm or leg coming into contact with the netting than with the cone-shaped type – especially on a double bed.
Mesh size: According to WHO recommendations, a net with holes about 2mm in diameter (that's a mesh count of around 61 holes per square centimetre or 156 per square inch) will stop even the smallest mosquito from squeezing through without impeding air flow. Check the mesh size on the packaging before you buy.
Easy portability: Your net needs to be light, compact, and quick to put up, take down and store in its carry bag – especially if you’re moving from place to place. You need to have this process down pat BEFORE you head overseas, so it pays to practise putting up your net and taking it down at least once at home.
Treated: ‘Treating’ a net means impregnating it with a contact insecticide. Treating it makes your net a lethal weapon against mozzies and other bugs, which are drawn to the CO2 and heat from the person sleeping beneath. Insecticides used to treat nets include permethrin, deltamethrin, lambda-cyhalothrin, alpha-cypermethrin, cyfluthrin, and etofenprox.
Advantages to DIY net treatment
You can purchase an untreated net and a DIY treatment kit, or buy a treated net.
Despite growing resistance to permethrin, it’s still the most commonly used for DIY treatment of nets and clothing. A synthetic pyrethroid, it’s derived from the crushed dried flowers of the Chrysanthemum cinerarifolium plant.
There are definite advantages to the DIY option. After soaking your net, you can use the leftover solution to treat the clothing to wear when biting bugs are at their fiercest – during the night, in the case of malaria-carrying Anopheles mosquitoes, or around dusk and dawn for the yellow fever, dengue and Chikungunya virus-transmitting Aedes species.
Permethrin kills virtually all insects on contact. A net is effective for 3-6 months of regular use, while treated clothing remains effective for 5-10 normal washes in hot or cold water.
Not everyone needs the extra protection of permethrin. Travelvax recommends it particularly to travellers who will be staying in areas where they can expect heavy infestations of insects or who’ll be travelling in rural areas during a peak season for insect-borne diseases – especially if they will be staying in budget accommodation without screens or air-conditioning.
Long life nets tops for longevity
However, a DIY net doesn’t retain its potency for as long as the latest pre-treated nets (which is fine if you’re travelling for a month or two and are happy to treat your net again next time).
Pre-treated nets like the PermaNet tick the boxes on quality, design and most importantly, longevity. PermaNet is accredited by the World Health Organisation as a LLIN or Long Life Insecticidal Net – one of only a few to meet the standard. (The WHO defines an LLIN as a factory-treated mosquito net that is expected to retain full insecticidal efficacy after at least 20 washes and for at least 3 years in the field under recommended conditions of use.)
Developed by Swiss company, Vestergaard Frandsen, the PermaNet technology allows for the slow release of the insecticide, deltamethrin to the net’s outer surface. Even after multiple washes and continuous use, no re-treatment or dipping is required to maintain the net’s efficacy, the company boasts.
Treated nets not only act as a physical barrier against bites by killing insects that land on the fabric, they also repel those just thinking about it. What’s especially great is that even with a few rents from normal wear and tear, a treated net will keep on killing insects.
Safe when used as directed
Treated nets can be used to protect children in beds, bassinets or strollers: the small quantity of insecticide a child might ingest by licking their hands after touching the net isn’t enough to cause any harm. However, there are safety concerns with the long-term use of some repellent and insecticides and it’s important to follow the directions for usage.
That said, experts in the field universally agree that the benefits treated nets and clothing deliver against potentially fatal insect-borne diseases far outweigh any risks.
In the absence of extensive Australian studies, the most useful safety guides come from the USA and include the CDC’s Insect Repellent Use and Safety and Permethrin Facts, from the Environmental Protection Agency (EPA).
Finally, it’s important to remember that contact insecticides only prevent bites from insects that actually land on the treated fabric – whether it be your bed net or clothing.
Topical repellent part of protective barrier
Unprotected skin needs another type of barrier: A topical (skin) repellent.
To be effective, your repellent should contain one of the recognised active ingredients – DEET, Picaridin, IR3535, or oil of lemon eucalyptus – and be reapplied according to its strength.
Formulations that contain 40% DEET will protect for 6 hours and are usually enough for most situations. Products containing 20%-30% protect for over 4 hours, while 10% formulations provide at least 2 hours’ protection.
Picaridin works just as well as DEET. It’s also odourless and a 20% formulation will protect for around 4 hours. Some oil of eucalyptus formulations last for up to 6 hours.
Most natural or organic repellents are not as effective.
Travelvax offers a range of effective repellents and impregnated nets (double and single) suitable for travel to the tropics and domestic use.
Read more about protecting yourself against biting insects. For further advice on staying healthy overseas, call Travelvax Australia’s free advisory service on 1300 360 164.