Why do some people get red spots while others get big blisters after being bitten by mosquitoes?

Audit expert: Zhang Yuhong

Chief Physician of Dermatology Department, Zhengzhou Central Hospital Affiliated to Zhengzhou University

Have you noticed what symptoms appear after being bitten by a mosquito? Why do some people get a small red dot while others get a huge mosquito bite? Today, I will take you to explore this secret~

Source: Internet

Is it dots or packages and what does it have to do with it?

Some people say that if your blood is sucked too much, a big mosquito bite will form, otherwise a small red dot will form; others say that it depends on each person's physique or the type of mosquito.

Mosquito Bag Source | Author

In fact, this is mainly related to the toxicity of the mosquito and the degree of response of our own immune system.

The immune system is composed of immune cells, immune organs and immune substances, which protect human health by fighting against foreign pathogens and mutant cells in the body. The blood, tissue fluid, secretion fluid and other body fluids of a normal human body contain a variety of substances that can kill or inhibit pathogens, such as lysozyme, defensins, phagocytic bactericidal factors, histones, etc. When pathogenic microorganisms such as bacteria and pathogens enter the human body, the macrophages in the immune system first enzymatically hydrolyze them into fragments and display them on their own surface as antigens.

When pathogens enter the body's blood, lymph and other parts, B cells (lymphocytes derived from the bone marrow, involved in humoral immunity) will be stimulated by external antigens and change their shape, increase in size, and become plasma cells, which can secrete antibodies to specifically bind and remove antigens, and exert humoral immune functions; and when pathogens enter cells, T cells (lymphocytes derived from the thymus, involved in cellular immunity) can play a cytotoxic role, remove antigens or foreign bodies, and maintain health. After the infection is suppressed for the first time, the immune system will remember the pathogen so that it can respond accurately and quickly if it encounters the same pathogenic substance invasion again.

Source of immune cells｜Pixabay

Generally, after being bitten by a highly toxic mosquito (such as a flower mosquito), you will experience stronger symptoms and itching. If you have never been bitten by a mosquito before, a mosquito flies over and inserts its mouthparts into the blood vessels of your subcutaneous tissue, and secretes some substances from the salivary glands to prevent blood clotting and prevent the mouthparts from being pulled out smoothly. After the mosquito finishes sucking blood and pulls out its mouthparts, the capillaries will bleed, forming a small bruise, and the mosquito's secretions will induce a little inflammatory reaction, which looks like a small red dot or erythema.

At this time, since your immune system cannot recognize this "foreign object", you will not get mosquito bites, but the immune system will remember it. The next time you encounter this mosquito bite, it will summon many immune cells within seconds and produce substances such as histamine and cytokines. These substances will dilate your capillaries, cause itching, and induce inflammation. Therefore, the mosquito bites will become large and itchy.

If you keep getting bitten by the same type of mosquito, the immune system will slowly become "numb", the body's reaction will weaken, and you won't get big mosquito bites anymore. Therefore, whether a mosquito bite turns into a red dot or a mosquito bite depends on how the immune system responds to it. But what we are discussing here is an ideal situation, and it is still very difficult to make the immune system "numb". Different mosquitoes secrete different substances in their salivary glands, and the immune system will "defend" again.

Source: Pixabay

How to scientifically relieve itching after mosquito bites?

We all have this experience: after being bitten by mosquitoes, if we don’t treat it, we will feel extremely itchy, and the more we scratch, the more itchy it becomes, and the more itchy it becomes, the more we scratch. So, how can we stop the itching caused by mosquito bites?

When you are first bitten by a mosquito, it will cause itching, redness and swelling of the skin. Do not scratch it at this time, as this may aggravate the symptoms and may also cause infection. You can apply floral water, wind oil or cooling oil to the affected area. The cooling feeling can suppress the itching and pain. Some aromatic substances in them are also effective in relieving redness, swelling and itching. If the mosquito bites the area around the eyes, nostrils, lips and other parts of the body, as well as the skin with wounds, the above-mentioned drugs should not be used.

Source: A shopping website

If you don't have the above topical drugs, you can use an ice pack or apply alcohol to the affected area to relieve the itching. Soapy water, aloe vera juice, etc. can also neutralize acidic toxins and relieve itching. It should be noted that some people like to pinch the affected area or scratch the affected area. This will not stop the itching, but will only irritate the affected area and may aggravate the symptoms.

When you have a strong reaction to a mosquito bite, such as a large lump, redness, swelling, inflammation, or ulceration, and the symptoms are serious, it is best to consult a doctor in time. If the affected area is infected, a few "small black spots" may be left after recovery. This is pigment accumulation, but there is no need to worry because it will slowly fade away over time.

As the main carrier of some diseases in summer, mosquitoes use their mouthparts to penetrate human skin to suck blood, and excrete their own saliva or venom, which invades our blood and causes dermatitis. In addition, the blood of the bitten person may remain on the mosquito's mouthparts, so when the mosquito bites the next person, it is very easy to cause cross-infection of blood and cause some blood-borne diseases. So everyone must pay attention to personal hygiene and mosquito protection!