TABLE 2.
Neurovirulence of DEN-2 16681, PDK-53, and recombinant 16681/PDK-53 viruses in newborn white ICR mice
| Virus (cognate)c | Mouse challengea
|
Virus genotypeb
|
||||||
|---|---|---|---|---|---|---|---|---|
| Mortality (%) | AST (SD) (days) | 5′-NC-57 | prM-29 | NS1-53 | NS2A-181 | NS3-250 | NS4A-75 | |
| DEN-2 16681 | 68.75 | 15.2 (1.2) | c | D | G | L | E | G |
| 30P-A (P513) | 81.25 | 14.6 (2.3) | · | · | · | · | · | · |
| P513 (16681) | 100.0 | 13.2 (1.6) | · | V | · | F | · | A |
| P51 (V3) | 50.0d | 15.9 (5.5) | · | V | · | F | V | A |
| P1 (V53) | 37.5d | 19.0 (4.2) | t | V | · | F | V | A |
| P13 (V5) | 37.5d | 13.5 (2.1) | t | V | · | F | · | A |
| P53 (V1) | 20.0d | 17.0 (7.8) | · | V | D | F | · | A |
| P5p (V13) | 6.25 | 15.0 | · | · | D | F | V | A |
| P5 (V13) | 6.25 | 27.0 | · | V | D | F | V | A |
| Pp (PDK-53) | 0 | —e | t | · | D | F | V | A |
| P3 (V51) | 0 | — | t | V | D | F | · | A |
| V3 (P51) | 75.0d | 16.4 (3.2) | · | · | · | · | V | · |
| Vp (16681) | 87.5 | 17.0 (0.9) | · | V | · | · | · | · |
| V53 (P1) | 18.75d | 21.3 (6.1) | t | · | · | · | V | · |
| V5 (P13) | 18.75d | 21.7 (4.2) | t | · | · | · | · | · |
| V5p (P13) | 6.25 | 20.0 | t | V | · | · | · | · |
| V13 (P5) | 6.25 | 17.0 | · | · | D | · | V | · |
| V1 (P53) | 6.25 | 22.0 | · | · | D | · | · | · |
| V51 (P3) | 0 | — | t | · | D | · | · | · |
| V513 (PDK-53) | 0 | — | t | · | D | · | V | · |
| VV45R (V513) | 0 | — | t | V | D | F | V | A |
| DEN-2 PDK-53 | 0 | — | t | V | D | F | V | A |
Percent mortality and AST of newborn, outbred white ICR mice challenged intracranially with 104 PFU of virus. There were 16 mice per group, except for the P53 and Vp groups, in which a single mouse died by day 1 after infection, presumably as a result of inoculation trauma. These two mice were excluded from the study.
See footnote a to Table 1 for explanation of virus genotypes. Dots indicate sequence identity with 16681 virus.
See footnote b to Table 1 for explanation of virus and cognate virus designations.
Mean body weight of surviving mice was significantly lower (P < 0.001, Student's t test) than that of diluent-inoculated control mice (not shown) at 3 weeks after infection.
—, not applicable because there was no mortality in this mouse group.