Emergency Medicine

Infectious Disease and Foreign Travel Emergencies 159

COMMON IMPORTED DISEASES OF TR AVELLERS

Malaria

DIAGNOSIS

1 Falciparum malaria is the most dangerous form of malaria. Cases are
imported to Australia from Africa, Asia and Papua New Guinea, but other
tropical sources include the western Pacific, Amazon basin and Oceania.
(i) Malaria is a potentially fatal infection. Survivors may experience
damage to the brain, kidneys, liver, heart, gastrointestinal tract
and lungs.
(ii) Cerebral malaria is an abrupt onset of encephalopathy with
headache that can progress rapidly to confusion, seizures and
coma.
(iii) Other malaria presentations include an influenza-like illness,
diarrhoea and vomiting, jaundice, acute renal failure, acute
respiratory distress, postural hypotension or shock, progressive
anaemia and thrombocytopenia.
(iv) The patient may not look ill in the first few days, but the non-
immune or splenectomized patient may then deteriorate rapidly
over a few hours and die.

2 The patient usually presents within 4 weeks of returning from a malarious
area with fever, rigors, nausea, vomiting, diarrhoea, and headache. Hepato-
splenomegaly is common.

3 Infection may persist for months due to the release of parasites from the
hepatic extra-erythrocytic phase in the liver, even after apparently success-
ful treatment.
(i) Late onset acute presentation can occur months or even more
than a year after return from overseas.
(ii) This relapse due to hepatic extra-erythrocytic phase does not
occur in falciparum malaria.

4 Send blood for FBC, coagulation profile, ELFTs, two sets of blood cultures
and:
(i) Request at least two sets of thick and thin blood films for malarial
parasites in every patient returning from abroad with fever and
with any of the above symptoms or signs.

5 Request an MSU.

MANAGEMENT

1 Falciparum malaria is a medical emergency requiring prompt treatment
wit h ora l or i.v. artemisinin derivative t herapy.
(i) Call the senior ED doctor if you suspect falciparum malaria.
(ii) Give immediate artesunate 2.4 mg/kg i.v. repeated at 12 and 24 h,
then once daily, if there is an altered conscious level, jaundice,