Every 4 months! Damn that must be hard. I have a colleague over here from Nigeria, I remember him vaguely mentioning how bad the malaria problem is in his country. And he was writing a paper on that. I even helped with stat analysis, but those numbers didn't hit me then. After reading your post I kind of have a bit more context to those numbers. These recurrences every 2-3 months are they relapses from the parasite sitting dormant in the hepatocytes of the liver. Or are we talking about frequency of reinfection with the parasite?