The mean gametocyte circulation time based on Pfs25 QT-NASBA gametocyte density after ACT and ACT-PQ. Log gametocyte density/μL is given on the Y-axis, the day of follow up after initiation of treatment. Symbols and error bars indicate the field data with 95% confidence interval, lines fitted values. The dotted line indicates the lower threshold for gametocyte detection by QT-NASBA, 0.02 gametocytes/μL. The trial was conducted in Tanzania; treatment regimens were ACT (closed triangles; SP+AS administered on day 0-2) and ACT-PQ (open squares; SP+AS administered on day 0-2 followed by a single dose of PQ on day 2). The mean circulation time of gametocytes in this trial was 4.61 days (2.92 - 7.26) after ACT treatment and 0.53 days (0.24-1.19) after ACT-PQ treatment.