I've had a recurring low-grade fever of 37.5°C for three days. What could be causing this, and what should I do?

Low-grade fever usually refers to a mild fever. Generally, recurring low-grade fever at 37.5°C for three days may be caused by factors such as catching a chill, improper diet, upper respiratory tract infection, pneumonia, or systemic lupus erythematosus. Patients should follow medical advice to choose general treatment, medication, and other symptomatic treatments. Detailed explanations are as follows:

1. Catching a chill: Exposure to cold may lead to decreased immunity, making it easier for bacteria or viruses to invade the body and cause infections, resulting in recurring low-grade fever at 37.5°C for three days. Symptoms may include chills, headache, and general fatigue. It is recommended that patients keep warm, avoid further exposure to cold, and ensure adequate rest to boost immunity.

2. Improper diet: Poor dietary habits may lead to malnutrition or weakened immunity, increasing the risk of infection and causing the aforementioned issues. Patients may also experience loss of appetite, nausea, and vomiting. It is advised to maintain a balanced diet, consume more fresh vegetables and fruits, and avoid raw, cold, greasy, or irritating foods.

3. Upper respiratory tract infection: Upper respiratory tract infections are usually caused by viral or bacterial infections, such as rhinovirus or adenovirus. These pathogens can affect the body's temperature regulation center, leading to recurring low-grade fever at 37.5°C for three days. Symptoms may include nasal congestion, runny nose, cough, and sore throat. Patients should take medications such as cefixime dispersible tablets, amoxicillin capsules, or oseltamivir phosphate capsules as directed by a physician.

4. Pneumonia: Pneumonia can be caused by various pathogens, including bacteria, viruses, or mycoplasma, which can trigger inflammatory responses in the lungs, causing the aforementioned symptoms. Additional symptoms may include cough with sputum, chest pain, and difficulty breathing. Patients are advised to use medications such as tinidazole capsules, erythromycin tablets, or potassium penicillin V tablets under a doctor's guidance.

5. Systemic lupus erythematosus: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the immune system attacking the body's own tissues and organs, causing damage to multiple systems. This inflammatory response can affect the body's temperature regulation center, resulting in recurring low-grade fever at 37.5°C for three days. Symptoms may include joint pain, muscle pain, fatigue, and rashes. Patients should take medications such as tripterygium wilfordii glycoside tablets, hydroxychloroquine sulfate tablets, or mycophenolate mofetil for injection as directed by a physician.

During treatment, the appropriate treatment plan should be selected based on the patient's specific condition, and medications and care should be administered in accordance with medical advice. Additionally, maintaining personal hygiene and making lifestyle adjustments can aid in recovery.