Summer beware of itchy rashes caused by insects
Hot and humid weather is a favorable condition for insects to thrive. Therefore, when working, playing... it is easy to get injured by insect bites and stings.
Insect bites are so diverse that they are difficult to distinguish. Some types can be dangerous, so treatment and prevention are necessary.
Common insects
- Mosquito :There are many species of mosquitoes in tropical climates, some species only bite without transmitting diseases, some species also transmit diseases: dengue fever, malaria...
After being "attacked" by mosquitoes, many people feel itchy, have red rashes, many people feel uncomfortable and have to scratch continuously. This causes damage to the epidermis, leading to inflammation.
The area of skin then becomes hyperpigmented, darker than the rest of the skin when the inflammation is gone. This hyperpigmentation is also known as a scar.
This condition is more severe in people with eczema, and the lesions will be more itchy. In cases of so-called "healthy skin", the rash will disappear within a few hours and often does not leave scars.
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Mosquito bites can transmit diseases: dengue fever, malaria... |
- Bed bugs:Often hiding in the crevices of objects in the house, after biting, they return to their hiding place. Symptoms of bed bug bites include: The appearance of small spots of 3-5, gradually growing, red. The bumps often appear on the hands, arms, shoulders, neck, face and legs; The bumps are itchy and may be accompanied by blisters.
-Fleas:Often parasitic on domestic pets: dogs, cats...
Fleas bite people to suck blood and cause scabies. In Vietnam, dog fleas and cat fleas (Ctenocephalides felis, Ctenocephalides canis) are commonly found.
The lesions are serous papules, 1-2mm in size, with edges higher than the skin surface, with small vesicles at the top of the papules, very itchy. In cases of strong reactions, there may be widespread inflammation and redness around the papules.
Lesions often occur on exposed skin or in areas of skin that come into direct contact with the animal when holding or handling them, such as: neck, face, arms, legs, and waist area.
In addition, fleas can be intermediate hosts for some diseases. The Oriental flea (Xenopsylla cheopis) transmits some diseases, rat-borne typhus to humans. Cat and dog fleas transmit tapeworms from one host to another…
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Insect bites often cause inflammation and redness, and in the early stages, the bite mark can be seen in the middle of the lesion. |
Identification of insect bites and treatment
At the site of insect bites, there is often inflammation and redness. In the early stages, the bite can be seen in the middle of the lesion. Then, the lesion gradually forms a serous papule or nodule. Patients are often bitten, so the most itchy is in exposed areas such as the lower limbs, forearms, face, and when bathing, the back and chest are also bitten.
After being stung, the puncture site bleeds after 5-30 minutes, leaving a rash like a mosquito bite, sometimes swollen like a bee sting, itchy.
The rash lasts for 3-6 hours, sometimes 7-10 days. The more you scratch, the itchier and more prominent it becomes. Scratching causes infection with pus and crusts, and when healed, it leaves dark scars. About 10% of the rashes gradually harden and thicken into lumps the size of beans or corn kernels. Sometimes the rashes become densely packed into lichenified lumps, causing intense itching and persistent progression.
Depending on the level of damage, the treatment is different.
Local treatment: Mild initial itching can be gently squeezed to bleed, apply 1% iodine alcohol, use balm oil, rub mugwort leaves,... on the affected area, avoid scratching to avoid infection.
In severe cases, antibiotic creams, ointments, and corticosteroids should be applied to reduce itching and prevent infection. If there are many bites, antihistamines, low-dose corticosteroids, etc. may be prescribed by a doctor.
If the patient shows signs of an allergic reaction to insect venom: fever, difficulty breathing, hives all over the body... the patient needs to be given emergency care at a medical facility.
Doctor's advice
The following simple measures can prevent insects that people need to take, especially in the summer, including cleaning the house, utensils, pets, etc. regularly.
Spray insecticides in the house and around the living area. Can use insect repellent products on the skin
When traveling or camping, cover your body with clothes, hats, socks and gloves when entering areas with a high risk of insect bites. Avoid using perfume and bright-colored clothing to reduce the risk of bee stings.
Control odors at picnics, garbage... places that can attract insects.
In the family and community, it is necessary to clean up, avoid stagnant water which will attract mosquitoes. Maintain good personal and household hygiene, regularly check and destroy fleas on cats, dogs and pets in the family.