Table 4. Vaccine efficacy evaluated for different follow-up periods.

	Engerix B (n = 92)				RTS,S/AS02D (n = 93)		Vaccine Efficacy
	Events	PYAR	Rate	Events	PYAR	Rate		95% CI	p
ATP(3–9)
First or only (FO) episode of fever and parasitemia >500/µl	34	31.5	1.08	21	38.2	0.55	48.8%	11.3–70.4	0.017
FO episode of fever or history of fever* and parasitemia >0/µl	48	27.7	1.74	29	36.4	0.80	54.5%	27.3–71.5	0.001
Multiple episodes of fever and parasitemia>500/µl	45	36.2	1.24	23	40.2	0.57	53.7%	21.4–72.7	0.004
Multiple episodes of fever or history of fever* and parasitemia >0/µl	72	36.0	2.00	34	40.0	0.85	58.9%	35.8–73.6	<0.001
ATP(3–14)
First or only (FO) episode of fever and parasitemia >500/µl	45	51.3	0.88	36	61.7	0.58	33.0%	−4.3–56.9	0.076
FO episode of fever or history of fever* and parasitemia >0/µl	57	41.4	1.38	45	57.1	0.79	41.9%	13.7–60.9	0.007
Multiple episodes of fever and parasitemia>500/µl	74	68.9	1.07	58	72.5	0.80	25.9%	−15.7–52.6	0.187
Multiple episodes of fever or history of fever* and parasitemia >0/µl	120	68.4	1.75	85	72.3	1.18	35.1%	2.2–57.0	0.039
ITT** (0–14)
First or only (FO) episode of fever and parasitemia >500/µl	54	79.4	0.68	46	90.2	0.51	25.9%	−9.9–50.0	0.136
Multiple episodes of fever and parasitemia>500/µl	105	111	0.94	82	113	0.72	24.3%	−12.9–49.2	0.173
Multiple episodes of fever and parasitemia>500/µl (PCD only)	95	112	0.85	80	113	0.71	17.6%	−24.2–45.3	0.355

*History of fever in previous 24 hours.

**ITT: n = 107 for each group.

PYAR =  Persons-years at risk. Vaccine efficacy adjusted estimates for area and distance from health center (km).

ATP =  According to the Protocol; ITT =  Intention to Treat; PCD =  Passive Case Detection.