Fig. 3.

(a) Replication of A2/08 in swine lungs. BALF was collected from DI pigs at 5 days p.i. and viral titres were determined as TCID₅₀ on MDCK cells. Values are shown as the log₁₀ TCID₅₀ ml⁻¹ for each infected pig. The pig ID corresponds to that shown in Fig. 2. (b) Pulmonary cytokine response induced by A2/08 in pigs. The levels of nine porcine (po) cytokines in BALF samples were determined by multiplex sandwich ELISA. TNF-α, Tumour necrosis factor alpha. (c) Virus shedding of A2/08. Groups of pigs were directly inoculated intratracheally with 10⁸ TCID₅₀ A2/08 per pig and three DC pigs were co-housed with the DI pigs on 1 day p.i. Nasal swabs were collected daily and titrated as TCID₅₀ on MDCK cells. Values in (b) and (c) are shown as mean±sem.