The following symptoms and complaints may indicate yellow fever:
1st phase
- Acute onset of illness with high fever, chills.
- Bradycardia – too slow heartbeat: < 60 beats per minute.
- Cephalgia (headache)
- Limb pain
- Myalgia (muscle pain)
- Epistaxis (nosebleed)
- Nausea (nausea)/vomiting
Only a small proportion of those infected with yellow fever become symptomatic, that is, show symptomsChildren usually have very mild courses. The acute symptoms usually persist for a few days (3-4 days). Most patients recover afterwards. In up to 15-20% of infected individuals, a 2nd phase of illness then occurs.
2nd phase (toxic phase)
- Faget sign – paradoxical occurrence of increasing relative bradycardia with increasing fever.
- Diarrhea, hemorrhagic (bloody diarrhea).
- High fever
- Hemorrhagic diathesis (bleeding tendency) – in the organs and skin due tovessel wall damage and blood clotting disorders.
- Icterus (jaundice)
- Hematemesis (vomiting blood; coffee grounds vomiting).
- Neurological disorders, which may be manifested by speech disorders, movement disorders, or convulsions, among other symptoms
- Severe organ damage (hepatocellular necrosis with histological evidence of Councilman bodies and clinical (scleral) icterus; glomerulus and tubule necrosis with uremia (increase in urinary substances in the blood above normal), oliguria (decreased urine volume with a daily maximum of 500 m) to anuria (less than 100 ml of urine in 24 hours)).
The lethality (mortality relative to the total number of people suffering from the disease) in the toxic phase is up to 50%.
