1 March 2002

But vaccine could be in the pipeline

COMPLETION of the genetic sequencing of DNA in bacteria responsible for cattle TB paves the way to improved testing and the development of a vaccine.

The mycobacterium bovis genome was sequenced in a three-year project funded by DEFRA and the Welcome Trust, VLA researcher Glyn Hewison told a London Press briefing.

Animal health minister Elliot Morley welcomed this breakthrough. "It will lead to the development of faster and more accurate cattle testing, which is essential in the fight against cattle TB."

The current test has limited reliability in certain circumstances, explained ISGchairman John Bourne.

"In higher risk areas, the test only has a reliability of 70-80%, which means that some animals remaining in herds may be inadvertent TB carriers."

In addition, the test only identifies infection when in the advanced stages and other related bacteria can produce false positive results, said Prof Bourne.

Using information from the genome, a specific test could be designed which reliably identifies TB infection earlier. Dr Hewison believes this could be available in the next 3-4 years.

A longer-term benefit of the genome sequencing is to develop a vaccine for cattle, said Prof Bourne. A more rapid solution could be to develop the human TB vaccine for use in wild animals. But there are large hurdles to be crossed, such as how to deliver it to wild animals &#42