Severe Plasmodium knowlesi malaria in a tertiary care hospital in Sabah, Malaysian BorneoArchived

ECDC comment

56 adult patients with PCR confirmed P. knowlesi malaria from Sabah are described. 22 (39%) of these had strictly defined severe malaria including respiratory distress, acute renal failure and shock. None had cerebral malaria. Eighteen patients were pregnant. Overall, six patients with severe malaria (27%) died, giving a case fatality rate of 27% for severe knowlesi malaria.

William T, Menon J, Rajahram G, Chan L, Ma G, Donaldson S, et al. Emerg Infect Dis. 2011 Jul;17(7):1248-55

ECDC comment: Although the proportion with severe disease is likely to have been biased by the fact that this report came from a referral hospital, this report emphasises how P. knowlesi can cause severe malaria and the case fatality rate is on a par with severe falciparum. The high proportion of pregnant women is also reminiscent of falciparum although cerebral disease is less common and respiratory distress more common in severe knowlesi disease. There are now two substantive reports of severe knowlesi disease from different geographical locations (the other been from Sarawak State, Malaysian Borneo) and it is becoming clear that in patients in certain parts of the world (and certain travellers to those regions), P. knowlesi is a potentially important cause of mortality and morbidity. The study also points out that artemisinin derivatives rapidly clear parasitemia and are efficacious in treating uncomplicated and severe knowlesi malaria.