Malaria, the raw facts

Tim Inglis

World impact

• common parasitic infection

• 1 million deaths each year

• mainly in children

• mainly in Africa

Disease patterns

1. stable unavoidable2. unstable preventable ?3. travel-related preventable

Clinical features

• Setting: history of travel to or residence in endemic area• Symptoms:

– COLD - initial shaking/rigor; then – HOT - fever (may be >40oC), restlessness, vomiting &

convulsions; then final – SWEATING - temperature returning to normal & possibly

sleep. • Timing:

– Generally days to weeks after return from endemic area– Overall, 6-10hr between paroxysms

MOSQUITO HUMAN

The parasite

a protozoan called Plasmodium

proboscis

palp

antenna

eye

scutum

scutellum

halter

THORAX

HEAD

ABDOMEN

FORE-LEG

WING

MID-LEG

HIND-LEG

femur

tibia

claw

tarsus

Its vectorfemale Anopheles mosquito

Investigations• Key questions:

– Does the patient have malaria? – Does the patient have P. falciparum malaria?– Does the patient have another infection?

• Blood films• Rapid tests• Other infections

Antimalarial treatmentWHO guidelines:

– ACT: Artemisinin-based Combination Therapy for uncomplicated malaria

– Artesunate for IV treatment in low transmission areas & later pregnancy

• General rules:

– start immediately if P.falciparum malaria– wait for results of blood film if benign malaria, – treat uncomplicated malaria as outpatient– advise return if worsens or no improvement

Expedition Medicine

• Personal measures– Personal protection– Chemoprophylaxis

• Group measures– Group prophylaxis– Area control measures– Rapid tests– Antimalarial therapy, SBET

• Local people• Medevac arrangements

The Anopheles mosquito is a self-propagating, self-propelled syringe armed to the teeth with malaria parasites.