Fight Against Malaria Takes Odd New Turn

by Sean McLachlan on


A new study has found a possible way to stop at least one species of mosquito from giving you malaria – by infecting them with a special strain of bacteria.

Researchers have found that infecting mosquitoes with the Wolbachia bacterium makes it nearly impossible for malaria to survive in the insects, thus keeping them from spreading it to humans, the BBC reports. The technique was tested on Anopheles stephensi, a species that ranges from the Middle East to Asia. An example is shown here in this Wikimedia Commons image. This remarkable photograph shows the insect sucking blood from a human. It’s become so engorged it’s actually ejecting extra blood from its rear end. Sorry if you were eating when you saw this but hey, it’s in the name of science.

The bacteria passed from female mosquitoes to their offspring, opening up the possibility of infecting the entire species. Researchers followed 34 generations of infected mosquitoes and found the bacteria passed on through all of them. The results have been published in the journal Science. A study last year showed the same bacteria can be used to stop dengue fever.

The technique has not yet been tried on Anopheles gambiae, the main source of malaria in Africa.

This potential breakthrough in the fight against malaria is coming along at an important time, now that mosquitoes are developing a resistance to DEET.

Mosquitoes Becoming Immune To DEET, Study Suggests

by Sean McLachlan on


According to a new study, mosquitoes are learning to ignore DEET, the BBC reports.

Researchers at the London School of Hygiene and Tropical Medicine tested the responses to DEET by the Aedes aegypti, a type of mosquito that can carry yellow fever and dengue fever and is thus particularly dangerous to adventure travelers.

In a new study published in the journal PLOS ONE, researchers say that while mosquitoes are at first repelled by DEET’s smell, they soon become accustomed to it and can return bite the wearer. Electrodes attached to the insects’ antennae show that they adjust to the scent of DEET and simply stop smelling it.

This is something I’ve heard campers and hikers comment on for quite some time now. Spending time in mosquito-ridden Missouri, I’ve noticed this trend myself. Missouri has about 55 known types of mosquito, including the Aedes aegypti.

An earlier study has raised questions about DEET being a neurotoxin. It looks like science’s next task is to find a better insect repellent.

I’ve also noticed that mosquito coils, which do not have DEET as an active ingredient, no longer seem to work on Missouri mosquitoes either. I enjoy sitting on the porch swing of my friend’s house reading. It used to be that a burning coil set nearby would keep the bugs away. No more. The last time I tried it the little bastards were attacking me so much I actually put the coil under the porch swing so the smoke rose right onto me. The mosquitoes didn’t seem to care. I soon retreated inside.

[Photo of Aedes aegypti courtesy US Department of Agriculture]

Mosquito Repelling Gear: It Works

by Pam Mandel on
The last thing you want to bring home from your safari? Malaria. And if you’re a bug attractor like me, it’s not just the anti-malarials you’ll want to pack. You’ll also want a good sized helping of DEET infused goo. And some stuff made from fabrics that have mozzie repelling properties.

Once you’ve caved in to the fact that you’re going to be a khaki covered dork, your life will get a lot easier. Start with the BugsAway shirt from ExOfficio. In addition to UV protection, it’s made with Insect Shield, a fabric infused with permethrin, a bug repellent, that holds through 70 washings.

I liked this shirt a lot. I liked the side vents that let air in along the back, I liked the securely zippered pockets, I liked the cut. It comes in a couple of colors, not just khaki. It’s wrinkle resistant, so I could stuff it in my day pack and just shake it back out into shape. I wore my BugsAway shirt almost every evening in camp and in the buggier beach towns. The result? None of those nasty through the shirt mozzie bites. This is a great travel shirt, a fine addition to a tropical travel wardrobe. The shirt is 88.00 from ExOfficio — you might want to check out their complete BugsAway line.

I also wore an Cocoon Insect Shield sarong on a number of occasions. I wore it to the beach, I while hanging out on tour bus, in the tropics I used it as an extra layer over the paper thin sheets provided at my hotels. I wore it as a scarf on the safari rig and used it as a beach towel. Mine was a preview model — they’re not yet out on the US market, but keep an eye on the Cocoon site if you want one.

I always pack a wrap of some kind, it’s the most versatile and useful item. The bug proof features of this one meant that the I had a skirt/scarf/wrap that also kept the biters at bay. I got a minimal number of bites during my travels to mosquito choked places, and none of them were on the areas covered by the sarong or my bug proof shirt.

The rest of my clothing I sprayed down with Ultrathon insect repellent. Good for six weeks or six washings, it worked well and didn’t leave any detectable chemical smell in my clothing. I far preferred the treated clothing options to slathering myself with bug repellent; that stuff smells, gets sticky, and I was relieved to have to use it just on my exposed extremities.In addition to packing mosquito-proofed clothing, I included a sleeping bag liner/sleep sheet. Mine was cotton and also came from Cocoon. I was pleased that I’d decided to bring it along. Not only did it keep me from using the perfectly disgusting hotel sheets in Nairobi, it also provided just the right weight of coverage for those hot nights in camp. The liners are 36.00 and come in three colors.

The mosquitoes liked my sleep sheet no more than they liked my bug proof clothing, which is to say not at all. During my two week trip, I received the most bites the night I went tromping through the grass in the darkness without applying repellent to my sock-less feet and ankles. It was my own fault.

“Don’t get bit,” is one of the primary pieces of advice the doctor at my local travel clinic pushes on travelers bound to areas with mosquito or other bug-borne illnesses. It costs a little bit more to add bug repelling attire to your travel kit, but it’s worth it. This stuff works.

Wacky sign of the week – what does this mean?

by Scott Carmichael on

I’m not entirely sure why, but this sign scares the crap out of me. I’ve never been a big fan of insects, but anything warning me about bugs twice my size is something I’ll pay attention to (even though it could be a fake sign).

I’m guessing the sign is a warning about big mosquitoes in a swamp area, but I’m also guessing that you are far more creative than I am – so, what do you think this sign means?

Leave your thoughts in the comments below.

Ten Bugs You Really Want To Avoid

by Kraig Becker on

One of the scariest things when you travel is encountering crazy insects in the places you visit. For some reason, I always seem to encounter bugs the size of my hand that look like something out of Aliens and generally pack a pretty nasty bite and/or sting.

Seems I’m not the only one, because the gang over at Environmental Graffiti have put together a list of the 10 most diabolical insects on Earth, with some down right nasty bugs making an appearance. For instance, cockroaches make the list in the number 10 spot. According to the story there are more than 4000 different species of cockroaches, many of which can grow quite large. And lets not forget the ever popular hissing cockroach that make foul noises to go along with their other foul habits.

Mosquitos earn their number 2 ranking by virute of the deadly diseases they have a propensity to spread. The article says that this tiny insect may be responsible for the death of over half the humans that have ever lived thanks to malaria and yellow fever. And that’s just the beginning of the scary mosquito facts.

The other eight bugs are just as nasty and will probably make your skin crawl. But if you like creepy crawly things, you’ll get a kick out of the list.

So, what’s the craziest bug you’ve seen while traveling?