The One Good Thing About Mosquitoes
Most of us think of mosquitoes as being innately bad, or even evil, but researchers have recently found a way to get some good out of them. Taking a closer look at the mosquito's needle-like mouth (known as the fascicle), engineers have discovered a way to make our own needles less painful. Utilizing serrated edges, a flexible tip, and vibration, the new needle design promises to make going to the doctor for vaccines and blood tests virtually painless, opening doorways for future medical interventions.
Researchers from Ohio State University and the Indian Institute of Technology have teamed up to find out how it is, exactly, that mosquitoes can bite us without us noticing it. Rather than using this information to prevent future mosquito bites, which could decrease the number of global malaria cases and global deaths, they want to develop a new type of needle to be used in hospitals and medical centres that has little-to-no pain involved.
Fascicle - The tube-like mouth of the mosquito
Insertion force - The force needed to push a needle through skin
Labrum - The stretchy covering around the fascicle
Using a scanning electron micrograph to nab some close-up views of the mosquito fascicle show that the overall reason why mosquito bites hurt less than needles is because the insertion force of the fascicle is over three times lower than the world's smallest needle. When insertion force is low, the needle will shift and deform the skin less as it is pushed in, which then causes less nerves to be affected and for pain to be lower. So how does the mosquito get insertion force to be so low? It turns out there are multiple bits of ingenious design that help a mosquito's mouth slide in easier. That's what she said.
Firstly, we've discovered that the sharp, piercing part of the mosquito's mouth is actually surrounded by an elastic covering called the labrum, which slides back as the needle part is inserted. It helps to stabilize the super thin fascicle so that is doesn't bend or buckle as it's being inserted. Without this covering, the fascicle would need to be much thicker to prevent breakage.
Look at this cocky blood-sucker. Legs up in the air, not a care in the world. Little does he know, we're stealing his trade secrets.
James Gathany, CDC - Aedes aegypti CDC08 - Wikimedia Commons (Public Domain)
Using depth-sensing nano-indentation techiniques (a fancy way of poking things and seeing how they react to figure out how hard or flexible they are), we can look at the make-up of the covering to see that it's the softest right at the tip. While this sounds counterintuitive for a needle, the slightly soft tip is thought to even further decrease the insertion force required to push the needle through the skin.
It was also found that the mosquito also has an additional, smaller needle inside of its fasicle that dispenses a numbing agent. The numbing agent makes the needle hurt less, but might not be as important in a clinical needle design since we could also use topical aneasthetics while giving shots or drawing blood.
Is this new needle design enough of a reason to prevent us from eradicating all mosquitoes everywhere? Hardly. I would argue, in fact, that now that we've sucked the last few drops of goodness out of them (pun fully intended), that we should go ahead and get rid of them. We know they would do the same to us.SaveSaveSaveSaveSaveSaveSaveSaveSave