Fig. 1

Plasmodium knowlesi-infected kra monkeys control parasitaemia without antimalarial treatment and develop persisting parasitaemias. a Afternoon peripheral parasitaemias determined by thick and/or thin blood films for 15 kra monkeys infected with about 100,000 cryopreserved P. knowlesi H strain sporozoites. Dashed line indicates approximately 40,000 parasites/µl or about 1% parasitaemia. The four animals above the bold horizontal line were sacrificed during the acute phase, and the 11 below were sacrificed after parasitemia became chronic. b Time to patency analysis for the 15 kra monkeys shown in a. c Average parasitaemia for each animal during the indicated time period after infection. Light gray bars indicate mean of the shown datapoints. Statistical significance was assessed using a linear mixed-effect model followed by a Tukey–Kramer HSD post-hoc analysis. p-values of < 0.05 were considered statistically significant. Asterisks indicate statistical significance