- It may be asymptomatic, mild illness (uncomplicated malaria) or severe illness (severe malaria)
- Intermittent fever is the most characteristic symptom of malaria. Three classical stages can be distinguished in a typical attack of malaria:
- The cold stage: the patient feels cold and shivers
- The hot stage: the patient feels hot
- The sweating stage: associated with sweating and relief of symptoms
- A complete physical examination has to be performed in any patient presenting with fever or history of fever
- When people are frequently exposed to malaria, they develop partial immunity. In such people, the classical stages of a malaria attack above may not be observed
- Also, in people who have had partial treatment with antimalarial medicines, these classical stages may not be pronounced
Uncomplicated Malaria
Common symptoms/signs of uncomplicated malaria
- Fever: above 37.5°C (taken from the axilla ) or history of fever
- Loss of appetite, mild vomiting, diarrhoea
- Weakness, headache, joint and muscle pain
- Mild anaemia (mild pallor of palms and mucous membranes); occurs commonly in children
- Mild dehydration (dry mouth, coated tongue, and sunken eyes). In adults, sunken eyes are usually a sign of severe dehydration
- Enlarged spleen (in acute malaria it may be minimally enlarged, soft and mildly tender)
Complicated/Severe Malaria
It is an immediate threat to life and is therefore a medical emergency. Malaria is regarded as severe if there are asexual forms of P. falciparum in blood plus one or more of the following complications in the table below.
Classical definition of severe malaria
Severe dehydration Sunken eyes, coated tongue, lethargy,
inability to drink
| COMPLICATION | CRITERION FOR DIAGNOSIS |
|---|---|
| Defining manifestations | |
| Cerebral malaria | Deep coma (unable to localise a painful stimulus), Normal CSF, parasitaemia |
| Severe anaemia | Hb <5g/dl with parasitaemia (<7 g/dl in pregnancy) |
| Respiratory distress |
Tachypnoea, nasal flaring and intercostal recession in a patient with parasitaemia |
| Hypoglycaemia | Blood glucose <40 mg/dl (2.2 mmol/L) with parasitaemia |
| Circulatory collapse |
Clinical shock (systolic pressure <50 mmHg for children and <80mmHg for adults, with cold peripheries, clammy skin) with parasitaemia |
| Renal failure | Urine output < 12 ml/kg in 24 hours and plasma creatinine > 3.0 mg/dl, with parasitaemia |
| Spontaneous bleeding |
Parasitaemia with unexplained spontaneous bleeding (haematemesis, melaena, or prolonged bleeding from nose, gum or venipuncture site |
| Repeated convulsions |
2 or more convulsions in 24 hours, with parasitaemia |
| Acidosis | Deep (acidotic) breathing and plasma bicarbonate <15 mmol/L, with parasitaemia |
| Haemoglobinuria | Parasitaemia, haemoglobin in urine (dark coloured urine but no RBC’s) |
| Pulmonary Oedema |
Deep breathing, fast breathing, laboured breathing (nasal flaring, intercostal recession and chest indrawing), Cheyne stokes breathing |
| Supporting manifestations (some other signs in addition to above complications) |
|
| Impaired consciousness |
Parasitaemia with depressed level of consciousness but can localize a painful stimulus, or change of behavior, confusion, drowsiness |
| Jaundice | Parasitaemia with unexplained jaundice |
| Prostration | Unable to sit, in a child normally able to do so or unable to drink in one too young to sit |
| Severe vomiting | Vomiting everything, not able to drink or breastfeed |
| Hyperpyrexia | Temperature >39.50 C, with parasitaemia |
| Hyperparasitaemia | Parasite count > 250,000 /μl, > 10% |
| Threatening abortion |
Uterine contractions and vaginal bleeding |