Volume 9, Number 9—September 2003
Research
DNA Vaccine for West Nile Virus Infection in Fish Crows (Corvus ossifragus)
Table 1
Effect of route of administration of a DNA West Nile virus vaccine on the protection of fish crows from challenge with virulent West Nile virus
Treatmenta,b | No. tested | % seropositivec | % viremic | Peak viremiad | % survival |
---|---|---|---|---|---|
Room control |
10 |
0 |
0 |
<1.7 (0.0) |
100 |
IM |
9 |
56 |
67 |
2.9b (0.4) |
100 |
Oral |
8 |
0 |
88 |
5.2c (0.8) |
50 |
Placebo | 10 | 0 | 100 | 4.3c (0.3) | 50 |
aIM, intramuscularly. Crows were inoculated IM with 0.5 mg of the DNA vaccine. Oral, crows were given 0.5 mg of the DNA vaccine orally. Placebo, crows were inoculated IM with 0.5 mg of nonspecific DNA and given 0.5 mg of nonspecific DNA orally.
bRoom controls were placebo inoculated and then challenged with diluent.
cPercentage of crows whose serum produced >80% neutralization at 1:20 dilution.
dLogarithm10 mean peak viremia in crows bled every third day after challenge (S.E.). No virus was detected in any of the room control birds and a value of 1.7 was assigned to birds from which no virus was detected for calculation of mean and S.E. Means followed by the same letter are not significantly different at α = 0.05 by student t test.