[Think of malaria!].

A drug addict, treated because of a lung abscess, was found to have plasmodium vivax malaria and was treated accordingly. The second patient acquired falciparum malaria inspite of chloroquine prophylaxis and was admitted with a thrombocytopenia of 24 000 mm3. After chloroquine treatment the platelet count became normal. Thrombocytopenia is usually present in falciparum malaria. Complications and their treatment are discussed.