New Zealand, however, has only recently reported the disease and, as yet, it is not widespread in what is a small industry.

Some interesting features of their outbreaks are already apparent, reports veterinarian Mark White in his NADIS report (see next issue of Pig World.)

• No live pigs have been imported into the country for 20 years or so.
  
  

• Semen has been imported but is believed not to have been used in the affected farms.
  
  

• All the affected sites are geographically close - on the North Island near Auckland.
  
  

• All the affected sites have links to each other in terms of pig supply, personnel movement and feed supplies.
  
  

• Most affected sites are "waste feeders" and for some time, due to a lapse in regulations, the waste included meat containing material from airports.
  
  

• There has, as yet, been no horizontal spread of clinical disease out of this core of units into sites with high standards of biosecurity.

• The disease entered the pigs in meat products.
  
  

• There is a single infectious entity that has spread through and between units, triggering classic disease (Porcine Circovirus Type II has been present in New Zealand pigs for many years.)

"The observation of a new infectious agent causing this devastation echoes the views of British clinicians since 1999," says Mark White. "It remains very disappointing that the bulk of research continues to concentrate on what many of us believe is the wrong bug."

Footnote: NADIS (National Animal Disease Information Service) is a network of 40 veterinary practices and six veterinary colleges monitoring diseases in cattle, sheep and pigs. It is sponsored by Meat and Livestock Commission, Elanco Animal Health and Intervet.