Malaria: Non-Falciparum

Key points

• The most common cause of non-falciparum malaria is Plasmodium vivax, with Plasmodium ovale and Plasmodium malariae accounting for the other cases.
• general features of malaria: fever, headache, splenomegaly
• Plasmodium vivax/ovale: cyclical fever every 48 hours. Plasmodium malariae: cyclical fever every 72 hours
• Plasmodium malariae: is associated with nephrotic syndrome Ovale and vivax malaria have a hypnozoite stage and may therefore relapse following treatment. Treatment
• TREATMENT (UK malaria treatment guidelines): EITHER an oral ACT OR chloroquine may be used for non-falciparum malaria. An oral ACT is PREFERRED for a mixed infection, where the species is uncertain, or for P. vivax acquired from areas where chloroquine resistance is common (Grade 1B).
• RADICAL CURE: chloroquine and other blood schizonticides do NOT kill liver hypnozoites, so a second drug is required. PRIMAQUINE is the only currently effective hypnozoitocidal drug (Grade 1A) and works better when given at the same time as chloroquine (Grade 1C) · relapse occurs in more than 25% of vivax patients treated with chloroquine alone.
• G6PD IS THE KEY SAFETY STEP: measure G6PD activity BEFORE primaquine in P. vivax or P. ovale — primaquine can cause severe haemolysis in G6PD deficiency, so it must be avoided or given only under expert supervision.
• PREGNANCY: primaquine is CONTRAINDICATED in pregnancy and while breastfeeding (until the infant's G6PD status is known) · instead give weekly chloroquine prophylaxis until after delivery or cessation of breastfeeding, then consider hypnozoite eradication · chloroquine itself is safe throughout pregnancy for non-falciparum malaria.
• A mixed infection that includes falciparum, or an infection with an unidentified species, must be treated AS FALCIPARUM in the first instance.