How is it caused that a mosquito bite takes a long time to heal?

After being bitten by a mosquito, if redness, swelling, and hard lumps persist for a prolonged period, they may be caused by the following reasons: 1. **Allergic reaction**: Some individuals are sensitive to proteins in mosquito saliva. A mosquito bite may trigger a strong allergic reaction, causing persistent redness and swelling. 2. **Bacterial infection**: Failure to clean the bite promptly or improper wound care may allow bacteria to enter the wound, causing infection and worsening the redness and swelling. 3. **Fungal infection**: Under certain conditions, the wound may become infected with fungi, leading to increased redness, swelling, and itching that is slow to resolve. 4. **Nerve damage**: In some cases, mosquito bites may damage nerves, resulting in delayed wound healing and persistent swelling. 5. **Chronic diseases**: Conditions such as diabetes, which involve abnormal blood glucose levels, may impair wound healing and cause prolonged redness and swelling following a mosquito bite. Persistent symptoms after a mosquito bite may be due to various factors including allergy, infection, nerve damage, or chronic diseases. If concerned, it is recommended to seek timely medical evaluation.