Malaria
Management
Mild P. falciparum malaria: P. falciparum is now resistant to chloroquine and sulfadoxine-pyrimethamine almost worldwide, so an
artemisinin-based treatment is recommended. Co-artemether (artemether and lumefantrine) is given 4 tabs at 0, 8, 24, 36, 48 and 60 hrs.
Alternatives are quinine (600 mg quinine salt 3 times daily for 5–7 days), followed by doxycycline or clindamycin. Doxycycline should be avoided in pregnancy and artemether in early pregnancy. WHO policy is moving towards artemisinin-based combination therapy (ACT).
Complicated P. falciparum malaria: Severe malaria (parasite
count > 2% in any non-immune patient) is a medical emergency.
Immediate management should include IV artesunate (2.4 mg/kg
IV at 0, 12 and 24 hrs, then daily for 7 days). When the patient has
recovered sufficiently, oral artesunate 2 mg/kg once daily is given
instead of infusions to a total cumulative dose of 17–18 mg/kg. IV
quinine salt is an alternative, with ECG monitoring. Management of
the complications of severe P. falciparum infection is summarised in
Box 5.20.
Non-falciparum malaria: P. vivax, P. ovale and P. malariae infec-
tions should be treated with oral chloroquine (600 mg chloroquine
base, followed at 6 hrs by 300 mg, then 150 mg twice daily for 2
more days). Relapses can be prevented by taking one of the antimalarial drugs in suppressive doses. Radical cure is achieved in
P. vivax and P. ovale using primaquine (15 mg daily for 14 days),
which destroys the hypnozoite phase in the liver. Haemolysis may
develop in those who are glucose-6-phosphate dehydrogenase
(G6PD)-deficient. Cyanosis due to the formation of methaemoglobin
in the red cells is more common but not dangerous.
Prevention
Choice of prophylactic agent is determined by the risk of malaria
in the area being visited and the degree of chloroquine resistance.
A variety of agents are used, e.g. chloroquine, atovaquone plus
proguanil (Malarone), doxycycline and mefloquine. Updated recom-
mendations are summarised at www.fitfortravel.nhs.uk. Many
agents require to be taken in advance of travel and continued after
return. Mefloquine is useful in areas of multiple drug resistance but
contraindications exist. Use of insecticide-treated bed nets, insect
repellents and protective clothing are also important means of
reducing infection. Vaccines against malaria are under development
but not yet fully protective.