Mosquito bites can quickly become a holidaymaker's nightmare. But how can such small perforations cause such itching? We explain to you.
Among the most terrifying sounds in the world , the sharp whirr of the wings of a mosquito wins by far the palm. These little creatures have the gift of ruining our summer nights, making the threat of the dreadful bites and the itching that ensue over our skin. But why are mosquito bites itching as much?
A Swiss army knife as a mouth
Mosquitoes are pollinators : they usually feed on the nectar of flowers. However, in order to acquire the necessary nutrients to produce their eggs , the female mosquitoes (which are the only ones to sting, you fear nothing from the males) must turn to another source of food. That's why they have the ability to pierce the skin of a host to consume blood . We talk about ectoparasitism.
To do this, mosquito mosquito is not armed with a single trunk, but six mouthparts (protected by a retractable envelope called labium ) that will help him sting his victim. The part intended to suck the blood, called labrum , is beveled in the manner of a blood sampling needle. Its path through the skin is facilitated by maxilles , two needles similar to tiny saws equipped with teeth , while two other needles, the mandibles , spread the tissues to facilitate sting.
Finally, the last needle, the hypopharynx , is responsible for injecting us with a good dose of mosquito saliva. And it is here that the itching makes their appearance!
Saliva and itching
This saliva indeed has an anticoagulant function : it prevents the blood from becoming too complicated to suck for the female. When saliva arrives in your body, it sees - rightly - a foreign body. He defends himself against the invader, causing redness and swelling (nothing to do with a novel by Dostoevsky), but also itching.
This last manifestation is related to the production of histamines , solicited in case of immediate allergic response, and also responsible for physiological manifestations such as urticaria. That's why saliva causes such itching. (It can unfortunately also carry parasites that cause serious diseases such as malaria).
How to calm the itching?
Several tips are available to calm the itch. One of the most important is not to scratch. The more you scratch, the more the sensation will continue or even intensify. However, you can apply an ice cube that will numb the area and scratch around the button rather than above, which will prevent it from doubling volume.
Finally, if the sensation is really unbearable you can use a steroid cream : by causing the constriction of your blood vessels, it will reduce the inflammation causing the itching. And now, now you know everything. And if you just get stung, good luck!