Malaria, a disease caused mainly by the parasites Plasmodium falciparum and Plasmodium vivax, is associated with over 400,000 deaths each year. Previously, the spleen was assumed to mostly play a role in parasite destruction, as it eliminates malaria parasites after antimalarial treatment. A study published by Steven Kho and Nicholas Anstey at Menzies School of Health Research, Australia, and international colleagues, suggests that in chronic P. vivax infections, malaria parasites survive and replicate via a previously undetected lifecycle within the spleen.