The venom of the three-cavity ant is 12-15 times stronger than that of the cobra venom.

In recent weeks, the Central Dermatology Hospital (Hanoi) has received dozens of cases of skin lesions caused by ant bites. Many cases of skin lesions include burning, redness, ulcers, and secondary infections. Most patients self-treat at home but do not get better, and only come to the hospital when the lesions are severe and widespread.

Doctor Nguyen Tien Thanh, Vietnam Dermatology Association, said that contact dermatitis caused by ants is a common disease in the rainy season, appearing on exposed skin areas such as the face, neck, arms, and legs in the morning after a night's sleep.

The disease is caused by the ants not by stinging but by secretions that stick to the skin, causing local contact dermatitis. The ants' bodies contain the toxin Pederin (C24H43O9N), which is 12-15 times more toxic than cobra venom, but because the amount of contact is small and only on the skin, it is not enough to kill a person like snake venom, but will cause severe damage to the skin, burning and stinging.

Initially, the patient feels a slight itching and burning sensation, and the skin becomes tight. After 6-12 hours, the burned area will be slightly swollen, red, and streaked with large and small blisters. 1-3 days later, blisters and pus will form, and the pain and burning sensation will increase. The patient may have widespread damage to the surrounding area, fever, general discomfort, skin infection, and post-inflammatory hyperpigmentation.

If treated, it will go away after a week. If treated late, the skin lesions can leave red scars that take months to heal. If their toxins get into the eyes, they can cause conjunctivitis and swelling of the soft tissue around the eyes, and in some cases, temporary blindness.

Dr. Thanh said it is necessary to distinguish between contact dermatitis caused by ants and shingles, because these are two completely different diseases. Misdiagnosis and using the wrong medicine will affect the treatment process, possibly making the disease worse and the recovery process longer.

Shingles is caused by a virus that affects the skin and nerves. Patients will feel more pain in the affected area. The disease manifests as clusters of blisters, vesicles filled with clear fluid, growing in clusters on a red skin background, distributed on one side of the body and along the nerve path, often occurring in the chest, head, face, neck and buttocks. In addition, patients may experience fatigue, fever, headache... When the disease is cured, it can leave persistent post-herpetic pain that affects the patient's quality of life.

The Department of Preventive Medicine, Ministry of Health, recommends that people replace fluorescent lamps with yellow lamps, because ants love fluorescent light. Before going to bed, sweep the house to clean the floor and hang a mosquito net to avoid insects. When the environment has a high density of ants, spraying residual ant killer on the walls inside and outside the house will help repel and kill them.

Dr. Thanh warns against touching or crushing ants with bare hands; instead, use a tissue or object to remove them. If you accidentally crush or rub ants on your skin, quickly wash the contact area with clean water or saline, soap, and avoid touching other areas of your skin with hands that have come into contact with ants. After that, the patient should go to a medical facility for timely examination and treatment.

"Absolutely do not apply leaves, unverified remedies, or antiseptics containing iodine or alcohol, as this will make the wound worse and increase the risk of secondary infection," the doctor advised.