Fever

Last updated: December 2023

Fever is defined as an axillary temperature higher than 37.5 °C.

Fever is frequently due to infection. In a febrile patient, first look for signs of serious illness then, try to establish a diagnosis.

Signs of severity

• Petechial or purpuric rash, meningeal signs, heart murmur, severe abdominal pain, dehydration.

• Signs of severe bacterial infection or sepsis: critically ill appearance a Citation a. Critically ill appearing child: weak grunting or crying, drowsiness, difficult to arrouse, does not smile, disconjugate or anxious gaze, pallor or cyanosis, general hypotonia. , hypothermia, altered level of consciousness, severe tachycardia, hypotension, tachypnoea, respiratory distress, seizures; a bulging fontanel in young children.
• Signs of circulatory impairment or shock: see Shock, Chapter 1. 

Infectious causes of fever according to signs and symptoms

• If the patient is ill appearing a Citation a. Critically ill appearing child: weak grunting or crying, drowsiness, difficult to arrouse, does not smile, disconjugate or anxious gaze, pallor or cyanosis, general hypotonia. and has a persistent fever, consider HIV infection and tuberculosis, according to clinical presentation.

Laboratory and other examinations

• Malaria rapid diagnostic test in endemic areas.
•  In case of circulatory impairment or shock: see Shock, Chapter 1.  
• Children 1 to 3 months with fever without a focus:
  • urine dipstick and urine culture, if available;
  • blood culture, if available;
  • full blood count (FBC), if available;
  • lumbar puncture (LP) if meningeal signs or signs of severe bacterial infection or sepsis, or failure of prior antibiotic treatment;
  • chest x-ray, if available, in case of signs of respiratory disease or severe infection or sepsis.
• Children > 3 months to 2 years with fever without a focus:
  • urine dipstick and urine culture, if available;
  • LP if meningeal signs or signs of severe bacterial infection or sepsis;

• chest x-ray, if available, if fever > 72 hours or signs of severe bacterial infection or sepsis;
• blood culture, if available, if fever > 72 hours or signs of severe bacterial infection or sepsis;
• FBC, if available, if fever > 72 hours or signs of severe bacterial infection or sepsis;
• other: according to clinical presentation.

• Children over 2 years with fever without a focus:
  • urine dipstick and urine culture, if available, if history of urinary tract infection or fever > 72 hours or signs of severe bacterial infection or sepsis;
  • LP if meningeal signs or signs of severe bacterial infection or sepsis;
  • chest x-ray, if available, if fever > 72 hours or signs of severe bacterial infection or sepsis;
  • blood culture, if available, if fever > 72 hours or signs of severe bacterial infection or sepsis;
  • FBC, if available, if fever > 72 hours or signs of severe bacterial infection or sepsis;
  • other: according to clinical presentation.
• Adults: according to clinical presentation.

Aetiological treatment

• Treat patients with a positive malaria test: see Malaria, Chapter 6.
• If the source of infection has been found: administer antibiotic treatment accordingly.

• If severe infection, sepsis, circulatory impairment or shock: hospitalise and immediately administer an empiric antibiotic treatment (see Shock, Chapter 1). Continue this treatment until the source of infection is found and adapt antibiotic treatment accordingly.

• If no source of infection is found, and there are no signs of severe infection, sepsis, circulatory impairment or shock, hospitalise for further investigations and monitoring:
  • Children 1 to 3 months;
  • Children > 3 months to < 2 years with negative urine dipstick (and negative urine culture if available).

• For malnourished children, see Severe acute malnutrition, Chapter 1.

• For patients with sickle cell disease, see Sickle cell disease, Chapter 12.

Symptomatic treatment

• Undress the patient. Do not wrap children in wet towels or cloths (not effective, increases discomfort, risk of hypothermia).
• Antipyretics may increase the patient’s comfort but they do not prevent febrile convulsions. Do not treat for more than 3 days with antipyretics.

paracetamol PO 
Children 1 month and over: 15 mg/kg 3 to 4 times daily (max. 60 mg/kg daily)
Adults: 1 g 3 to 4 times daily (max. 4 g daily)
or
ibuprofen PO
Children over 3 months and < 12 years: 5 to 10 mg/kg 3 to 4 times daily (max. 30 mg/kg daily)
Children 12 years and over and adults: 200 to 400 mg 3 to 4 times daily (max. 1200 mg daily)
or
acetylsalicylic acid (ASA) PO
Children over 16 years and adults: 500 mg to 1 g 3 to 4 times daily (max. 4 g daily)

Prevention of complications

• Encourage oral hydration. Continue frequent breastfeeding in infants.
• Look for signs of dehydration.
• Monitor urine output.

Notes:

• In pregnant or breast-feeding women use paracetamol only.
• In case of viral haemorrhagic fevers and dengue: acetylsalicylic acid and ibuprofen are contraindicated; use paracetamol with caution in the presence of hepatic dysfunction.