Farmers are one step closer to seeing a deployable bovine TB cattle vaccine as government field trials move on to a third phase.
Following the completion of phase 2 of the trials, the government has published an update confirming it will undertake an additional phase.
Phase 3 will provide an opportunity to collect more data from a wider group of cattle to inform options to optimise the performance and reliability of the DIVA (Detect Infected Among Vaccinated Animals) test.
A cattle vaccine for bovine TB, along with the new DIVA Skin Test, is set to bring hope to many farmers in the fight for bTB eradication.
Experts say that vaccinating cattle has the potential to protect individual animals and halt disease spread within herds and populations.
The DIVA Skin Test (DST-F) is another innovative tool for bTB testing in vaccinated cattle populations.
Specifically, the test is designed to distinguish between cattle vaccinated with the BCG (Bacillus Calmette-Guérin) vaccine and those infected with Mycobacterium Bovis, the bacterium which causes bTB infection.
Ele Brown, the UK's deputy Chief Veterinary Officer, said: “This next step in the ongoing field trials reflects our commitment to providing robust assurances of test performance for our farmers and vets.
“Along with colleagues in Scotland and Wales, we will continue to assess how this potential new tool could be deployed and provide the greatest possible benefit to our herds for generations to come.”
The results of the latest field trial of 300 vaccinated and 300 unvaccinated cattle offer confidence in safety to support a future marketing authorisation application.
However, results indicate that there is still a need to collate further data on test performance.
Two animals on a participating farm exhibited reactions equal to or above the proposed positive cutoff point of > 2mm.
Many factors may have induced this reaction, and this next phase of testing protocol assessment aims to enhance diagnostic accuracy across settings.
The criteria for the next phase will aim to inform practical disease control solutions for bTB in vaccinated herds.
Responding to the trials, NFU President Tom Bradshaw said it was vital that farmers had access to all the tools to reduce bTB in cattle, including vaccines and badger culls.
"Both are needed, and they would represent a significant step forward in the fight against bTB, so it is essential that everything is done to make sure it is the most effective it can be when it is made available for use.
“We cannot afford to get this wrong. Further field trials are needed to help provide us with a vaccine for cattle that will play a vital role in the future eradication of this terrible disease.”
