Malaria

Malaria

• Protozoan parasites→ plasmodium falciparum

• Bite of female anopheles mosquitoes

Malaria Life-Cycle

Anopheles Mosquito (night bite) → Ingests infected blood → Parasites reproduce in mosquito gut → Thousands of sporozoites produced → Mosquito bites new person → Sporozoites injected → Travel to liver → Mature into merozoites → Enter red blood cells → RBCs rupture → Release more merozoites → Haemolytic anaemia + fever spikes

Fever Presentations In Malaria

• P. vivax / P. ovale → Every 48h (Tertian Malaria)

• P. falciparum → Frequent / irregular (Subtertian)

• P. malariae → Every 72h (Quartan Malaria)

Presentation Of Malaria

Malaria should be suspected in someone that has travelled to an area where malaria is present. The incubation period is usually 1-4 weeks after exposure, although it can lie dormant for years.

Many of the symptoms are non-specific:

• Fever (up to 41ºC) with sweats and rigors

• Fatigue

• Myalgia (muscle aches and pain)

• Headache

• Nausea

• Vomiting

Signs On Examination Of Malaria

• Pallor due to the anaemia

• Hepatosplenomegaly

• Jaundice (bilirubin is released during the rupture of red blood cells)

Most Common Symptom Of Malaria

Fever→ spikes very high every 48 hours

Investigation For Malaria

• Malaria blood film via EDTA bottle

• Three negative samples over three days required to exclude malaria

Management Of Malaria

Oral options for uncomplicated malaria include:

• Artemether with lumefantrine (Riamet) is the usual first choice

• Quinine plus doxycycline

• Quinine plus clindamycin

• Proguanil with atovaquone (Malarone)

• Chloroquine (there are increasing rates of resistance to chloroquine)

• Primaquine (can cause severe haemolysis in patients with G6PD deficiency)

Management Of Severe Malaria

• Artesunate is the usual first choice (haemolysis is a common side effect)

• Quinine dihydrochloride

Complications Of Malaria

• Cerebral malaria

• Seizures

• Reduced consciousness

• Acute kidney injury

• Pulmonary oedema

• Disseminated intravascular coagulopathy (DIC)

• Severe haemolytic anaemia

• Multi-organ failure and death

Antimalarial Medications

• Proguanil with atovaqoune→ 2-7 days before travel

• Doxycycline→ 2 days before - 4 weeks after travel→ may cause diarrhoea or thrush

• Mefloquine→ 2 weeks before - 4 weeks after travel → psychiatric symptoms