Volume 10, Number 12—December 2004
Dispatch
Genome Sequence and Attenuating Mutations in West Nile Virus Isolate from Mexico
Table 2
Neuroinvasiveness and neurovirulence of TM-171 Mex03 parental isolate and plaque-purified variants after injection into 3- to 4-week-old female NIH Swiss micea
Virus | E154-156 sequence | i.p. LD50 (PFU) | i.p. AST ± SD (d)b | i.c. LD50 (PFU) | i.c. AST ± SD (d)b |
---|---|---|---|---|---|
TM171-03 | NYP/S | 1.3 | 7.9 ± 0.7 | 0.8 | 6.2 ± 1.8 |
TM171-03-pp1 | NYP | >1000 | NA | 32 | 6.0 ± 0.9 |
TM171-03-pp2 | NYP | >1000 | NA | 25 | 6.7 ± 1.7 |
TM171-03-pp5 | NYS | 2.0 | 9.0 ± 1.4 | 2.0 | 7.4 ± 1.2 |
TM171-03-pp6 | NYS | 2.0 | 8.5 ± 1.7 | 1.3 | 7.4 ± 0.9 |
aNIH, National Institutes of Health; AST, average survival time; i.p., intraperitoneal; i.c., intracranial; LD50, 50% lethal dose; SD, standard deviation; NA, not applicable.
bAverage survival time ± SD was calculated for all animals that died following inoculation with 1,000 - 0.1 PFU doses of indicated virus.