15 September 2000

CSF source identified

AN infected pork product imported from the Far East is thought to be the most likely source of the current swine fever crisis.

In a letter to Vet Record (Sept 9), MAFF State Veterinary Service and VLA scientists say that while the source of disease has not been conclusively identified, they have been investigating a number of potential sources.

Their research has found that CSF viruses recovered from the first five cases and identified are similar to strains found in the Far East and Europe.

They say pigs were probably first exposed to the virus in early June 2000, and only certain sow groups were infected. Four further cases occurred on rearing premises supplied by the breeding herd between June 27 and Aug 1.

Detailed investigations have ruled out many of the hypotheses put forward as to the means of infection, and researchers believe that an infected pork product is the most likely source.

A review of legal imports into the UK has failed to reveal a potential source from the Far East, but they say illegal imports can occur and may include contaminated products.

The researchers say that as the first infected farm was an outdoor unit, pigs can be exposed to waste food dropped on pasture. "A variety of wild birds and mammals are seen locally, and a public footpath passes close to those pig paddocks where, from current evidence, infection was introduced."

Further investigations are under way, and the scientists are due to report their results and analyses once these have been completed. &#42