What causes sudden fever of 39°C accompanied by body aches?

Fever of 39°C generally refers to a body temperature of 39°C. Sudden onset of fever at this level accompanied by whole-body aches may be caused by conditions such as influenza, novel coronavirus infection, bronchitis, urinary tract infection, or acute leukemia.

1. Influenza

When the body's resistance decreases and bacterial infection occurs, the immune system may be activated to fight the bacteria, leading to elevated body temperature and inflammatory responses. Symptoms include fever, muscle aches, headache, runny nose, and sneezing. Under medical guidance, medications such as Compound Paracetamol and Amantadine Capsules, Ganmaoling Granules, or Cold Soft Capsules can be used to relieve fever and pain, thereby improving symptoms.

2. Novel Coronavirus Infection

After infection with the novel coronavirus, viral replication may trigger an immune response, resulting in the release of inflammatory mediators that cause symptoms such as fever and muscle pain. Additional symptoms may include cough and sore throat. Treatment under medical supervision may involve antiviral drugs such as Azvudine tablets, Molnupiravir capsules, and Nirmatrelvir tablets to suppress viral replication and alleviate symptoms.

3. Bronchitis

Inflammation of the bronchial mucosa caused by pathogenic microorganisms can lead to swelling of the tracheal and bronchial mucous membranes, causing symptoms such as cough, sputum production, wheezing, and shortness of breath. Systemic inflammatory responses may also result in fever and general discomfort. Under medical guidance, antibiotics such as Roxithromycin capsules, Azithromycin dispersible tablets, or Amoxicillin capsules may be prescribed to inhibit or eliminate bacteria, control infection, and promote recovery.

4. Urinary Tract Infection

Pathogens ascending into the bladder, fallopian tubes, or other areas can cause infection. If the infection spreads, it may lead to fever, muscle aches, and urinary symptoms such as urgency, frequency, and dysuria. Doctors may prescribe sensitive antimicrobial agents such as Ceftriaxone for injection, Ceftazidime for injection, or Cefixime capsules to control the infection and support improvement.

5. Acute Leukemia

Excessive proliferation and accumulation of hematopoietic cells in the bone marrow and peripheral blood can suppress normal blood cell production, leading to anemia, thrombocytopenia, and other manifestations. This may result in elevated body temperature, fatigue, muscle pain, easy bleeding, and bone pain. It is essential to follow medical advice and use interferon therapy, which exerts immunomodulatory, anti-proliferative, and antiviral effects to combat tumors and improve symptoms. Commonly used drugs include recombinant human interferon α1b for injection, pegylated interferon α-2a injection, and recombinant human interferon α2b injection.

Seeking timely medical treatment upon experiencing these symptoms helps promote recovery. Additionally, maintaining adequate rest and a light diet in daily life can aid in symptom relief.