Summer is fast approaching for the southern hemisphere, and in many regions that means mosquitoes. Entire legions of them, ready to bite everything in their path. The pain, the itching, the sleepless nights, the sticky, smelly ointments… we are forced to battle their bites. But it's not a bad idea to understand how they work. In our minds, we imagine it's “a pinch and done”, yet there is a more complex and disturbing mechanism behind it…
The mosquito is the most lethal animal on Earth. It's not hard to imagine humans claiming the top spot, but if we count only murders, human deaths amount to 475,000 per year, while mosquitoes kill an average of one million people in the same period. Malaria, dengue, zika, chikungunya… mosquitoes are formidable vectors, and they leave us no choice but to wage war against them.
One of the most striking examples of anti-mosquito campaigns is found at Disney World. Florida, wetlands, open spaces, heat… the perfect combination for a cloud of blood-sucking insects to devour visitors. But Mickey Mouse has proven remarkably good at killing mosquitoes, almost as good as extending copyright laws. Yet at the end of the day, mosquitoes win, bite, and hurt. Why? How exactly do mosquitoes bite us?
The six needles of a mosquito bite
The first idea we must dispel is that of a simple penetration with the proboscis. The first step is retracting the protective lip (forming a sort of arch), revealing not one but six “needles”. Two of them (maxillae) have teeth at their ends and are used to pierce the skin. The second pair of needles (mandibles) hold the tissue apart. The fifth needle (labrum) has a double function: on one hand, receptors at its tip help the mosquito detect a blood vessel, and on the other, it extracts the precious liquid.
While feeding, the mosquito separates the blood from the water, a highly efficient process to get more from each bite. With the last needle (hypopharynx), the mosquito injects saliva and chemicals that delay the immune response, optimize blood circulation, and by extension, improve its feeding. This is what sickens and kills humans. Of course, the mosquito gains nothing from it, but viruses and parasites definitely take advantage of any opportunity to spread.
Preventing mosquito bites
To finish, a classic recommendation: the most effective way to reduce mosquito presence is to prevent their reproduction. Larvae need water, but if we eliminate any accumulation in old containers and other abandoned objects (e.g., tires), we can block their arrival at the adult stage.
https://old.neoteo.com/como-las-garrapatas-se-clavan-en-tu-piel-con-su-boca-de-pesadilla-video/Source: NPR
