Bluetongue certification -- Australian policy.

Australian quarantine policies with respect to BT are based on regarding this disease as one of high risk and major potential economic importance to our ruminant population. There are deficiencies in our knowledge of world distribution, epidemiology and pathogenesis. There may be unknown vectors and unsuspected animal reservoir hosts. The international distribution of BT could be extending through the movements of insects or cattle. If introduced into Australia, the cattle and sheep populations would probably be at continuous risk as eradication would be difficult or impossible. Costs to the sheep industry at least could be high and productivity gravely affected. To reduce the probability of introduction, imports of ruminants and semen have, for the last 16 years, been restricted to a very small number of countries presumed free from BT. Future policies will almost certainly be based on these same considerations taking into account scientific advances in diagnosis and virus detection. The establishment of an off-shore high security quarantine station will facilitate imports of ruminants even from known BT-infected countries.