TABLE 2.
Reports of adverse effects of select live-attenuated RVFV vaccines in pregnant livestocka
| Vaccine | Gestation period | Dose and/or delivery route | No. of pregnant animals with spontaneous abortions/total no. of animals vaccinated (%) | Effect(s) on fetuses | Description | Reference(s) |
|---|---|---|---|---|---|---|
| Smithburn or MLVV | Not reported | s.c. | Cattle, 28/100 (28) | Early fetal death and mummification | Animals received multiple doses of formalin-inactivated vaccine prior to vaccination with Smithburn | 26 |
| Various (from both experimental and field vaccinations) | s.c., i.v., or i.d. | Sheep, 386/1,150 (44) | Stillbirths, teratogenesis, viremia | Hydranencephaly, hypoplasia (cerebrum, cerebellum, spinal), brachygnathia, arthrogryposis, scoliosis, hydrops amnii | 27 | |
| Clone 13 | Early gestation | 1 × 105 PFU s.c. | Cattle, 0/17 (0) | None reported | 30 | |
| Sheep, 0/17 (0) | ||||||
| Goats, 0/12 (0) | ||||||
| Late gestation | 1 × 105 PFU s.c. | Cattle, 0/8 (0) | None reported | 31 | ||
| Sheep, 0/30 (0) | ||||||
| Goats, 0/36 (0) | ||||||
| Late gestation (120 days) | 6.8 log10 TCID50/ml s.c. or i.d. | Sheep, 0/12 (0) | 0/28 teratogenicity | 32 | ||
| 4/28 (14%) viremic | ||||||
| MP-12 | Early gestation (28–56 days) | 1 × 106 PFU s.c. | Sheep, 2/50 (4) | 15–23% teratogenic effects in delivered lambs | Hydranencephaly, hypoplasia (cerebellum, spinal), prognathia inferior, brachygnathia, arthrogryposis, scoliosis, lordosis, kyphosis, domed head | 41 |
| Late gestation (90–110 days) | 5 × 103 PFU s.c. | Sheep (0) | None reported | NA | 39, 82 | |
| Early/midgestation (90 or 150 days) | 1 × 105 PFU s.c. to pregnant sow or i.m. directly to fetus | Cattle (0) | None reported | NA | 38, 40 | |
| ΔNSsΔNSm | Early (42 days) | 1 × 104 PFU s.c. | 0/29 (0) | None reported | No RVFV vRNA found in lamb tissues | 83 |
a
MLVV, modified live virus vaccine; s.c., subcutaneous; i.m., intramuscular; i.d., intradermal; i.v., intravenous; TCID50, 50% tissue culture infective dose; vRNA, viral RNA; NA, not applicable.