Table 3.
Assessment of safety and infectious activity of H7N3 LAIV when administered intravenous or intranasal in chickens.
| Intravenous pathogenicity | Intranasal pathogenicity and infectivity | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Morbidity (sick/ total) |
Mortality (dead/ total) |
Pathogenicity Index | Morbidity (sick/ total) |
Mortality (dead/ total) |
Virus recovery on the 3 dpi after intranasal inoculation with 6 log10 EID50/0.1 mL | Seroconversion on 14 dpi (ELISA) | |||||
| Swabs | Recovery from tissues | ||||||||||
| URP | Cloacae | Lungs | Heart | Kidneys | Brain | ||||||
| 0/8 | 0/8 | 0 | 0/8 | 0/8 | 0/10 | 0/10 | 0/2 | 0/2 | 0/2 | 0/2 | 0/8 |
4
Groups of eight chickens were infected intravenously with 8.1 log10 EID50/0.2 mL and observed daily for 10 days for clinical signs and death.
5
Groups of ten chickens were infected intranasally with 6 log10 EID50/0.1 mL. The oropharyngeal and cloacal swabs were collected 3 days p.i. and titrated in eggs for assessing viral replication. The chickens were observed for clinical signs of disease and death for 14 days. To determine infectivity, sera were collected 14 days p.i. and tested for the presence of antibodies by ELISA test
6
0 – absence of symptoms, 1 – development of infection signs, 2 – severe infection, 3 – fatal case