Table 3.
Maximum intensity of solicited symptoms and signs associated during inpatient days 8–18 (during which time malaria is expected) and stratified by volunteers who received ID challenge, those who received the high dose PfSPZ exposure of 50,000 and historical results from mosquito-transmitted (i.e., traditional) CHMI
| Inpatient stay (days 8–18) | ID CHMI all groups (A–F) (N = 29) | ID CHMI with 5 × 104 PfSPZ (E, F) (N = 10) | Traditional challenge—mosquito (N = 25) | P value ID vs. traditional* | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Reactogenicity | None n (%) | Mild n (%) | Moderate n (%) | Severe n (%) | None n (% of total) | Mild n (% of total) | Moderate n (% of total) | Severe n (% of total) | None n (%) | Mild n (%) | Moderate n (%) | Severe n (%) | |
| Oral temperature | 15 (51.7) | 3 (10.3) | 9 (31.0) | 2 (6.9) | 2 (13.3) | 0 | 6 (66.7) | 2 (100.0) | 6 (24.0) | 3 (12.0) | 5 (20.0) | 11 (44.0) | 0.037 |
| Malaise | 11 (37.9) | 9 (31.0) | 7 (24.1) | 2 (6.9) | 0 | 5 (56.0) | 4 (57.1) | 1 (50.0) | 6 (24.0) | 10 (40.0) | 9 (36.0) | 0 | 0.28 |
| Nausea | 17 (58.6) | 11 (37.9) | 1 (3.4) | 0 | 3 (17.6) | 6 (54.5) | 1 (100.0) | 0 | 13 (52.0) | 11 (44.0) | 1 (4.0) | 0 | 0.63 |
| Myalgia | 15 (51.7) | 7 (24.1) | 7 (24.1) | 0 | 1 (0.07) | 4 (57.1) | 5 (71.4) | 0 | 7 (28.0) | 11 (44.0) | 7 (28.0) | 0 | 0.13 |
| Headache | 12 (41.4) | 12 (41.4) | 4 (13.8) | 1 (3.4) | 2 (16.6) | 3 (25.0) | 0 | 0 | 3 (12.0) | 15 (60.0) | 7 (28.0) | 0 | 0.017 |
| Chills | 18 (62.1) | 4 (13.8) | 6 (20.7) | 1 (3.4) | 4 (22.2) | 1 (25.0) | 4 (66.7) | 1 (100.0) | 5 (20.0) | 11 (44.0) | 9 (36.0) | 0 | 0.002 |
| Vomiting | 25 (86.2) | 4 (13.8) | 0 | 0 | 7 (28.0) | 3 (75.0) | 0 | 0 | 21 (84.0) | 4 (16.0) | 0 | 0 | ns |
| Abdominal pain | 19 (65.5) | 9 (31.0) | 1 (3.4) | 0 | 7 (36.8) | 2 (22.2) | 1 (100.0) | 0 | 24 (96.0) | 0 | 1 (4.0) | 0 | ns |
| Diarrhea | 25 (86.2) | 3 (10.3) | 1 (3.4) | 0 | 7 (28.0) | 2 (66.7) | 1 (100.0) | 0 | 23 (92.0) | 2 (8.0) | 0 | 0 | ns |
| Dizziness | 24 (82.8) | 4 (13.8) | 1 (3.4) | 0 | 8 (33.3) | 1 (25.0) | 1 (100.0) | 0 | 13 (52.0) | 9 (36.0) | 3 (12.0) | 0 | ns |
| Arthralgia | 20 (69.0) | 4 (13.8) | 5 (17.2) | 0 | 5 (25.0) | 2 (50.0) | 3 (60.0) | 0 | 16 (64.0) | 4 (16.0) | 5 (20.0) | 0 | ns |
| Chest pain | 26 (89.7) | 3 (10.3) | 0 | 0 | 9 (34.6) | 1 (33.3) | 0 | 0 | 22 (88.0) | 3 (12.0) | 0 | 0 | ns |
| Shortness of breath | 25 (86.2) | 4 (13.8) | 0 | 0 | 8 (32.0) | 2 (50.0) | 0 | 0 | 22 (88.0) | 3 (12.0) | 0 | 0 | ns |
| Change in exercise Tolerance | 26 (89.7) | 1 (3.4) | 2 (6.9) | 0 | 5 (19.2) | 0 | 0 | 0 | 20 (80.0) | 4 (16.0) | 1 (4.0) | 0 | ns |
| Palpitations | 27 (93.1) | 2 (6.9) | 0 | 0 | 5 (18.5) | 0 | 0 | 0 | ND | ND | ND | ND | ND |
| Any systemic | 6 (20.7) | 9 (31.0) | 11 (37.9) | 3 (10.3) | 0 | 2 (22.2) | 6 (54.5) | 2 (66.7) | 0 | 5 (20.0) | 9 (36.0) | 11 (44.0) | 0.025 |
CHMI = controlled human malaria infection; ID = intradermal; PfSPZ = Plasmodium falciparum sporozoite. Bold values represent those calculations that reached statistical significance.
*
P value determined by Mantel–Haenszel Chi2 analysis (no symptoms vs. symptoms) or Fishers exact (2 tailed) as appropriate between ID CHMI (all groups) and traditional CHMI.