Pediatric Yellow Fever Clinical Presentation

Updated: May 04, 2017
  • Author: David J Cennimo, MD, FAAP, FACP, AAHIVS; Chief Editor: Russell W Steele, MD  more...
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The clinical spectrum of yellow fever (YF) ranges from a minimally symptomatic flulike illness to a catastrophic illness complicated by hemorrhage and organ failure (primarily the liver and kidney). It develops in a number of distinct phases (not all of which invariably occur).

The incubation period typically lasts 3-6 days. No prodromal symptoms occur.

The infection period of infection lasts 3-4 days. Viremia is present. Susceptible biting mosquitoes can be infected with YF. Symptoms typically begin abruptly with fever, chills, malaise, prostration, headache, dizziness, myalgia (particularly lumbosacral area), anorexia, nausea, and vomiting.

The remission period lasts 2-24 hours. Symptoms and fever abate.

The abortive phase may extend over 1 day or longer. Recovery occurs without further symptoms.

The period of intoxication may last 3-5 days. Liver failure, hemorrhagic diathesis, and kidney failure occur. This period develops in approximately 15% of all cases. This stage is fatal in 1-50% of cases that develop toxicity. Previous symptoms and new symptoms include fever with high temperatures, chills, anxiety, confusion, lethargy, prostration, jaundice, epistaxis, anorexia, epigastric pain, nausea, vomiting, hematemesis, melena, lumbosacral pain, and decreased urine output. Complications include bacterial pneumonia and sepsis.

The period of convalescence may last days to weeks. The patient recovers completely, without sequelae. Complications may include protracted weakness and fatigability.


Physical Examination

The Pan American Health Organization has published a case definition for YF to aid in surveillance. By this definition, YF is an illness characterized by acute onset of fever followed by jaundice within 2 weeks of the onset of first symptoms plus 1 of the following:

  • Bleeding from the nose, gums, gastrointestinal (GI) tract, or skin
  • Death within 3 weeks of illness onset

A case of YF is classified as suspected if it meets the clinical definition or if other causes of fever or jaundice are excluded. A suspected YF case can be confirmed by laboratory testing or by being epidemiologically linked to a laboratory-confirmed case or outbreak.

Data to be reported to public health authorities include patient-specific identifier, age or date of birth, location, laboratory results, vaccination history, outcome of infection (alive, dead, unknown), case classification, and date of death (if dead).

Physical examination findings are nonspecific and may include the following:

  • Fever
  • Pulse - Slow, inversely proportional to temperature (Faget sign)
  • Anxiety, lethargy, prostration, confusion, coma
  • Facies - Flushed
  • Conjunctival injection
  • Abdominal tenderness
  • Hemorrhagic manifestations - Epistaxis, gingival bleeding, hematosis, melena, hematuria
  • Urine output - Decreased
  • Shock


Complications of YF include the following:

  • Organ failure - Liver (secondary to hepatic necrosis), kidney (secondary to parenchymal injury and acute tubular necrosis), heart (secondary to parenchymal injury)
  • Hemorrhagic diathesis - YF virus directly injures the liver, kidney, and heart; a hemorrhagic diathesis progressing to disseminated intravascular coagulation (DIC) is not uncommon in the toxic form of the disease, because of hepatic damage, thrombocytopenia, and perhaps other factors
  • Secondary infections, particularly bacterial pneumonia