61 Causes of Fever (And How You Can Treat It)

Fever (febrile response, pyrexia) is defined as an increase in body temperature above 37°C. There is not a single figure agreed upon as the upper limit of temperature. Therefore most books use 36.6 – 37°C as the average body temperature. Most people feel hot or warm when touched if their temperature is above 37°C.

What are the signs of fever?

  • Chills
  • Fatigue
  • Feeling hot for a while then feeling cold
  • Sweating
  • Delirium
  • Irritability
  • Confusion
  • Problems concentrating or talking (babbling)

What are the types of fever?

There are different types of fever according to the pattern of temperature:

Intermittent fever 

Intermittent fever is the type of fever where temperature rises for a certain period of time and later cycle back to normal levels. The subtypes of this kind of fever are:

  • Quotidian fever (fever cycle back 24hrs after the original start of fever).
  • Tertian fever (fever cycle back after 48 hours)
  • Quartan fever (fever cycle back after 72 hours)

Examples of diseases that are caused by an intermittent pattern of high temperatures are pyaemia, sepsis, kala-azar, and malaria.

Continuous fever

Continuous fever is a high temperature that is continuous for a period of time and does not fluctuate more than 1°C per day. Examples of diseases that cause a continuous pattern of fever are typhoid fever, pneumonia, meningitis, and urinary tract infection.

Remittent fever

Remittent fever is a temperature that remains high throughout the day and fluctuates more than 1°C per day. Examples of diseases that cause a remittent pattern of fever are infective endocarditis and brucellosis.

What causes fever?

Fever is the body’s response to an infectious process, an illness, and any foreign substance, the body perceives as unsafe. Therefore there is a wide range of factors that triggers fever.

Here are the conditions where fever is a common symptom:

  1. Malaria
  2. Coronavirus
  3. Typhoid fever
  4. Hodgkin’s lymphoma
  5. Pneumonia
  6. Strep throat
  7. Rheumatoid arthritis
  8. Cystitis
  9. Pyelonephritis
  10. Glomerulonephritis
  11. Otitis media
  12. Vaccines
  13. Chemotherapy
  14. Sepsis
  15. Pyaemia
  16. Kala-azar
  17. Influenza (the flu)
  18. Ebola
  19. HIV/AIDs infection
  20. Infectious mononucleosis
  21. Gastritis
  22. Hyperthyroidism
  23. Peptic ulcer disease (stomach ulcer and intestinal ulcer)
  24. Dengue fever: it is a disease caused by the dengue virus through the bite of a mosquito
  25. Lyme disease
  26. Boils (furuncle): is an infection of a single hair follicle (folliculitis)
  27. Carbuncles (multiple boils): is an infection of numerous hair follicles that cause pus-filled bumps also known as boils
  28. Systemic lupus erythematosus (SLE)
  29. Sarcoidosis
  30. Amyloidosis
  31. Esophagitis
  32. Inflammatory bowel disease (ulcerative colitis and Crohn’s disease)
  33. Hemolysis
  34. Sickle cell anemia
  35. Crush syndrome
  36. Rhabdomyolysis
  37. Intracerebral hemorrhage
  38. Tissue destruction during surgery
  39. Myocardial infarction
  40. Cocaine use
  41. Kawasaki disease
  42. Hepatitis A, B, C, and E
  43. Liver cirrhosis
  44. Amphetamine use
  45. Temporal arteritis (giant cell arteritis)
  46. Polymyalgia rheumatics
  47. Granulomatosis with polyangiitis (Wegener’s granulomatosis
  48. Gout
  49. Leukemia
  50. Breast cancer
  51. Pelvic inflammatory disease (PID)
  52. Bacterial vaginosis
  53. Common cold
  54. Acute bacterial sinusitis
  55. Chickenpox
  56. Dehydration
  57. Overexposure to the sun can increase body temperature
  58. Cancer of the kidneys
  59. Pancreatitis
  60. Cholecystitis
  61. Finally, the fever of unknown etiology. This is a type of fever that lasts longer than three weeks without a known cause after a proper medical examination has been carried out.

How can you tell if you have a fever?

Fever is diagnosed by checking the body temperature with a thermometer. There are five places to check for temperature with a thermometer: oral, axilla (under the arm), rectal, forehead, and ear. You can also check if your temperature is high by placing the back of your palm to your forehead.

What is the best medicine for a fever?

Antipyretics such as paracetamol, ibuprofen, and aspirin can be used. Take these medicines according to the label instructions or as prescribed by your doctor.

Is it good to drink water during a fever? Yes, drink plenty of fluids is vital to keep the body from dehydration and also make sure you get plenty of rest.

Note: aspirin is not recommended for children and pregnant women.