Sunday, February 5, 2012

Mosquitoes Keep Their Cool

New research on how mosquitoes keep their cool is reported in sciencecodex.com
Mosquito- Wikimedia
If you have ever swatted a tiny mosquito and seen the blood left on your skin, you can imagine how much blood they can stuff in their body.  However, your warm blood creates a risk of overheating in this coldblooded insect.  You probably aren't feeling any sympathy yet for this poetic justice.

The study which was reported in Cell Press helps explain how the mosquito handles this heat stress.  A mosquito doesn't sweat like we do or pant like a dog.  Insects generally control their temperature by extruding fluid such as nectar or sap.  The mosquito puts itself at great risk of a crushing blow when it is sucking the blood it needs to reproduce. 

To cool itself, it apparently has to ooze out a little of that blood.  Using a heat sensing camera, researchers determined that the mosquito's head was the temperature of blood while the body remained cool.  The cooling was due to the loss of liquids out their backsides. Learning how this is controlled could be of practical value if a method of blocking or delaying the excretion of fluid could be developed.


The microbes on your skin determine how attractive you are to mosquitoes, which may have important implications for malaria transmission and prevention, according to a study published Dec. 28 in the online journal PLoS ONE.  Human sweat is odorless to our nose, so the mixture of microbes on your skin help determine your special body odor.

Eurekalert.org reports that researchers, from Wageningen University in the Netherlandsstudied the Anopheles gambiae sensu stricto mosquito, which plays an important role in malaria transmission.
"They found that individuals with a higher abundance but lower diversity of bacteria on their skin were more attractive to this particular mosquito. They speculate individuals with more diverse skin microbiota may host a selective group of bacteria that emits compounds to interfere with the normal attraction of mosquitoes to their human hosts, making these individuals less attractive, and therefore lower risk to contracting malaria.  This finding may lead to the development of personalized methods for malaria prevention."

The next time someone tells you that they always attract more mosquitoes than anyone around them, you might suggest that they try changing skin bacteria.  On the other hand, you might not.