But this is not the situation here. In the UK, we are arguing for an emergency, high potency vaccine used alongside slaughtering. In Algeria in 1999 the outbreak was brought under control before the time came to give the booster and the vast majority of cattle only received the initial injection. But the longer vaccination is delayed the more difficult the task will be. With high payload emergency vaccines protection can occur between 2 and 4 days of the primary injection, against airborne challenge.
Experimental studies indicate clinical protection and reduction in virus shedding occurs quickly.
The longer the period that elapses between vaccination and disease challenge, the higher the protection. It is true that we should assume that between 7 and 14 days post immunisation in cattle needs to elapse before we can assume a high proportion of animals will have sufficient immunity that little virus will be transmitted by them after disease challenge. But we know that in both pigs and cattle immunisation dramatically reduces the titre and duration of virus excretion. Of course, vaccination by itself is not the total answer. Appropriate slaughter is essential, as are movement controls and traceability.