Table 2.
Protection against blood-stage versus sporozoite challenge by CPS immunization
| Prepatent period, d, median (range) |
||||||
| Challenge | Protected/total no. of volunteers | Protection, % | Thick smear | PCR | Blood-stage parasite multiplication rate, median (range) | |
| Immunized | Sporozoite | 5/5 | 100 | N/A | N/A* | N/A |
| Blood stage | 0/9 | 0 | 8.0 (7.0–8.3) | 5.0 (3.0–5.3) | 8 (6-18) | |
| Control | Sporozoite | 0/5 | 0 | 12.3 (9.3–12.3) | 9.0 (7.0–10.0) | 10 (5-23) |
| Blood stage | 0/5 | 0 | 8.0 (8.0–8.3) | 5.0 (2.0–6.3) | 14 (7-24) | |
*
One subject became PCR positive on day 21 after challenge. N/A, not applicable.