Relationship between parasitemia, anemia, and reticulocyte count
| Response to infection . | Aotusno. . | Peak parasitemia % (day)† . | Day of treatment‡ . | Reticulocyte %*(Hematocrit %) . | ||||
|---|---|---|---|---|---|---|---|---|
| Day 7 (8) . | Day 14 (15) . | Day 21 (22) . | Day 29 (29) . | Day 36 (36) . | ||||
| Group 1: No microscopically detectable parasitemia; no anemia | 5231-153 | 0 | 2.8 (58) | 7.8 (53) | 1.5 (49) | 6.5 (56) | 4.9 (63) | |
| 5301-153 | 0 | 6.8 (64) | 5.9 (60) | 3.4 (64) | 2.3 (66) | 4.9 (68) | ||
| 5591-153,1-154 | 0 | 4.0 (58) | 3.5 (49) | 3.3 (46) | 6.3 (57) | 2.6 (61) | ||
| 6031-153 | 0 | 3.8 (44) | 1.5 (43) | 1.6 (44) | 2.3 (41) | 3.8 (40) | ||
| 7321-153 | 0 | 3.3 (62) | 4.2 (57) | 2.4 (50) | 12.7 (43) | 5.6 (52) | ||
| 546 | 0 | 5.1 (60) | 2.4 (56) | 5.2 (61) | 1.7 (66) | 2.5 (71) | ||
| 602 | 0 | 3.1 (65) | 2.7 (60) | 1.7 (54) | 3.0 (62) | 3.6 (68) | ||
| 680 | 0 | 2.4 (58) | 3.3 (57) | 4.8 (59) | 5.7 (62) | 3.0 (65) | ||
| 692 | 0 | 2.1 (59) | 5.5 (57) | 1.4 (60) | 1.3 (59) | 2.1 (57) | ||
| 747 | 0 | 2.8 (57) | 3.7 (51) | 3.4 (51)1-164 | 2.2 (50) | 7.6 (40) | ||
| 749 | 0 | 1.9 (53)1-160 | 3.0 (53) | 2.0 (50) | 1.9 (59) | 2.4 (53) | ||
| Group 2: No microscopically detectable parasitemia; positive by PCR; severe anemia (hematocrit lower than 25%) | 5671-153 | 0 | 22 | 2.9 (60) | 2.4 (52) | 2.1 (22)1-161 | 14.8 (28) | 10.8 (49) |
| 6571-153 | 0 | 15 | 4.4 (43) | 2.3 (20) | 16.4 (29) | 14.9 (37) | 11.1 (44) | |
| 6761-153 | 0 | 22 | 2.5 (56) | 1.5 (45) | 0.1 (19)1-161 | 20.8 (27) | 7.1 (48) | |
| 26111-153,1-159 | 0 | 21 | 9.6 (60) | 4.5 (45) | 0.0 (16)1-161 | 6.3 (43) | 1.5 (53) | |
| 557 | 0 | 17 | 3.5 (52) | 1.5 (29) | 17.9 (26) | 8.4 (18) | 4.9 (25) | |
| 7481-154 | 0 | 17 | 3.2 (55) | 2.9 (30) | 6.9 (22) | 7.9 (32) | 6.2 (50) | |
| Group 3: Parasitemia level lower than 5%; moderate anemia | 5131-153,1-154 | 3.61 (20) | 5.8 (57) | 2.1 (56) | 4.0 (34) | 11.3 (36) | 4.9 (47) | |
| 5601-153 | 0.41 (21) | 4.8 (62) | 3.5 (60) | 0.4 (48) | 24.5 (33) | 10.8 (55) | ||
| 5771-153 | 0.73 (21) | 5.0 (54) | 5.5 (53) | 1.9 (34) | 9.6 (49) | 3.4 (62) | ||
| 6271-153 | 0.14 (17) | 3.4 (57) | 1.4 (39) | 3.7 (27)1-164 | 11.6 (38) | 9.9 (46) | ||
| 738 | 0.36 (12) | 4.6 (62) | 3.8 (39) | 8.0 (37) | 3.5 (49) | 3.9 (52) | ||
| 5781-153 | 0 | 3.7 (44) | 3.8 (34) | 6.5 (39) | 7.8 (41) | 5.9 (57) | ||
| 6311-153 | 0 | 2.8 (59) | 4.5 (52) | 6.1 (39) | 6.0 (45) | 5.8 (54) | ||
| Group 4: Parasitemia level lower than 5%; severe anemia | 5951-153,1-154 | 0.31 (18) | 22 | 3.0 (56) | 1.3 (51) | 2.2 (19)1-161 | 6.4 (27) | 6.5 (49) |
| 6001-153 | 3.10 (21) | 22 | 4.1 (54) | 3.7 (52) | 3.9 (24)1-161 | 18.4 (34) | 7.1 (50) | |
| 6061-153 | 0.14 (19) | 22 | 3.5 (60) | 3.3 (49) | 1.8 (20)1-161 | dead | dead | |
| 26121-153,1-159 | 0.35 (21) | 24 | 2.9 (52) | 2.7 (45) | 4.4 (29) | 7.1 (29) | 6.6 (41) | |
| 5851-154 | 0.35 (12) | 16 | 6.2 (57) | 2.6 (30) | 8.6 (20) | 8.8 (36) | 10.4 (46) | |
| 604 | 0.20 (16) | 19 | 3.9 (57) | 2.5 (41) | 9.4 (23) | 7.4 (48) | 4.7 (54) | |
| Group 5: Parasitemia level equal to or greater than 5%; severe anemia | 6781-154 | 9.70 (14) | 14 | 5.3 (58) | 7.1 (22)1-161 | 11.2 (40) | 10.1 (59) | 5.6 (63) |
| Response to infection . | Aotusno. . | Peak parasitemia % (day)† . | Day of treatment‡ . | Reticulocyte %*(Hematocrit %) . | ||||
|---|---|---|---|---|---|---|---|---|
| Day 7 (8) . | Day 14 (15) . | Day 21 (22) . | Day 29 (29) . | Day 36 (36) . | ||||
| Group 1: No microscopically detectable parasitemia; no anemia | 5231-153 | 0 | 2.8 (58) | 7.8 (53) | 1.5 (49) | 6.5 (56) | 4.9 (63) | |
| 5301-153 | 0 | 6.8 (64) | 5.9 (60) | 3.4 (64) | 2.3 (66) | 4.9 (68) | ||
| 5591-153,1-154 | 0 | 4.0 (58) | 3.5 (49) | 3.3 (46) | 6.3 (57) | 2.6 (61) | ||
| 6031-153 | 0 | 3.8 (44) | 1.5 (43) | 1.6 (44) | 2.3 (41) | 3.8 (40) | ||
| 7321-153 | 0 | 3.3 (62) | 4.2 (57) | 2.4 (50) | 12.7 (43) | 5.6 (52) | ||
| 546 | 0 | 5.1 (60) | 2.4 (56) | 5.2 (61) | 1.7 (66) | 2.5 (71) | ||
| 602 | 0 | 3.1 (65) | 2.7 (60) | 1.7 (54) | 3.0 (62) | 3.6 (68) | ||
| 680 | 0 | 2.4 (58) | 3.3 (57) | 4.8 (59) | 5.7 (62) | 3.0 (65) | ||
| 692 | 0 | 2.1 (59) | 5.5 (57) | 1.4 (60) | 1.3 (59) | 2.1 (57) | ||
| 747 | 0 | 2.8 (57) | 3.7 (51) | 3.4 (51)1-164 | 2.2 (50) | 7.6 (40) | ||
| 749 | 0 | 1.9 (53)1-160 | 3.0 (53) | 2.0 (50) | 1.9 (59) | 2.4 (53) | ||
| Group 2: No microscopically detectable parasitemia; positive by PCR; severe anemia (hematocrit lower than 25%) | 5671-153 | 0 | 22 | 2.9 (60) | 2.4 (52) | 2.1 (22)1-161 | 14.8 (28) | 10.8 (49) |
| 6571-153 | 0 | 15 | 4.4 (43) | 2.3 (20) | 16.4 (29) | 14.9 (37) | 11.1 (44) | |
| 6761-153 | 0 | 22 | 2.5 (56) | 1.5 (45) | 0.1 (19)1-161 | 20.8 (27) | 7.1 (48) | |
| 26111-153,1-159 | 0 | 21 | 9.6 (60) | 4.5 (45) | 0.0 (16)1-161 | 6.3 (43) | 1.5 (53) | |
| 557 | 0 | 17 | 3.5 (52) | 1.5 (29) | 17.9 (26) | 8.4 (18) | 4.9 (25) | |
| 7481-154 | 0 | 17 | 3.2 (55) | 2.9 (30) | 6.9 (22) | 7.9 (32) | 6.2 (50) | |
| Group 3: Parasitemia level lower than 5%; moderate anemia | 5131-153,1-154 | 3.61 (20) | 5.8 (57) | 2.1 (56) | 4.0 (34) | 11.3 (36) | 4.9 (47) | |
| 5601-153 | 0.41 (21) | 4.8 (62) | 3.5 (60) | 0.4 (48) | 24.5 (33) | 10.8 (55) | ||
| 5771-153 | 0.73 (21) | 5.0 (54) | 5.5 (53) | 1.9 (34) | 9.6 (49) | 3.4 (62) | ||
| 6271-153 | 0.14 (17) | 3.4 (57) | 1.4 (39) | 3.7 (27)1-164 | 11.6 (38) | 9.9 (46) | ||
| 738 | 0.36 (12) | 4.6 (62) | 3.8 (39) | 8.0 (37) | 3.5 (49) | 3.9 (52) | ||
| 5781-153 | 0 | 3.7 (44) | 3.8 (34) | 6.5 (39) | 7.8 (41) | 5.9 (57) | ||
| 6311-153 | 0 | 2.8 (59) | 4.5 (52) | 6.1 (39) | 6.0 (45) | 5.8 (54) | ||
| Group 4: Parasitemia level lower than 5%; severe anemia | 5951-153,1-154 | 0.31 (18) | 22 | 3.0 (56) | 1.3 (51) | 2.2 (19)1-161 | 6.4 (27) | 6.5 (49) |
| 6001-153 | 3.10 (21) | 22 | 4.1 (54) | 3.7 (52) | 3.9 (24)1-161 | 18.4 (34) | 7.1 (50) | |
| 6061-153 | 0.14 (19) | 22 | 3.5 (60) | 3.3 (49) | 1.8 (20)1-161 | dead | dead | |
| 26121-153,1-159 | 0.35 (21) | 24 | 2.9 (52) | 2.7 (45) | 4.4 (29) | 7.1 (29) | 6.6 (41) | |
| 5851-154 | 0.35 (12) | 16 | 6.2 (57) | 2.6 (30) | 8.6 (20) | 8.8 (36) | 10.4 (46) | |
| 604 | 0.20 (16) | 19 | 3.9 (57) | 2.5 (41) | 9.4 (23) | 7.4 (48) | 4.7 (54) | |
| Group 5: Parasitemia level equal to or greater than 5%; severe anemia | 6781-154 | 9.70 (14) | 14 | 5.3 (58) | 7.1 (22)1-161 | 11.2 (40) | 10.1 (59) | 5.6 (63) |
Treatment was given for hematocrit lower than 25% or parasitemia equal to or greater than 5%.
Normal reticulocyte count for Aotus monkeys: 2.9% ± 2.2% (arithmetic mean ± 2 SD deduced from 34 monkeys never exposed to malaria or vaccination).
0 = not microscopically detectable or only 1 or 2 parasites seen in 29 days.
All animals not previously treated were treated on day 29.
Immunized before first infection; all others immunized between first and second infections.
Vaccinated with control antigen GST; all others vaccinated with MSP-119.
A vociferans monkeys; all others were A nancymai.
Hematocrit % on day 5.
Hematocrit % on day 23.
Reticulocyte % determined on day of treatment.