Growing concerns that bluetongue infections may be going unreported

New fears have been raised that some bluetongue infections, as well as efforts to protect flocks and herds from the virus, may be going unreported.

One prominent clinician admitted she remains “quite scared” of the impact the disease could still have amid concerns about low vaccination levels. But an East Anglia-based vet argued that strong take up in her area has reduced case levels so far this summer.

A total of 22 BTV-3 cases, all in England, have been recorded since the beginning of July, and officials have described the transmission risk as “very high”.

But while bluetongue is classed as a notifiable disease, meaning reporting suspicions of it is compulsory, concerns about a potential lack of reporting were raised during an AHDB webinar on 20 August.

‘Myth-busting’

Giving what she described as a “myth-busting” presentation during the session, specialist sheep vet Fiona Lovatt said analysis of the virus’s impact had indicated previous restrictions imposed in the event of cases being detected had been considered “arduous” by some participants.

But she stressed that local restrictions would only be imposed now if another notifiable disease was detected.

She said: “We all need to know what the situation actually is. Please don’t think we’re out of the woods just because we haven’t yet had a lot of cases reported.”

‘Nowhere near’

Dr Lovatt also argued that modelling analysis of disease levels carried out during the BTV-8 outbreak of 2007-8 was applicable to the present situation, but warned present inoculation levels were “nowhere near” the 50 per cent take up scenario outlined in that study.

She said: “To suppress the disease, we need a lot of animals vaccinated. I’m still scared of bluetongue and what might happen.”

Steve Jackson, the Welsh Government’s head of animal disease policy, also described the take up there as “fairly low”, despite figures suggesting more than 200,000 animals have been vaccinated so far, based on vet-recorded data.

Vet and farmer data

However, he was particularly concerned by a discrepancy between veterinary-recorded and farmer-recorded data, with the latter only indicating that around 127,000 animals have been vaccinated so far.

Mr Jackson conceded that further relaxation of movement restrictions would increase the risk of the virus crossing the border from England, but acknowledged industry concerns about the impact of those restrictions on businesses.

But Laura Stephen, vet and director at the Isle Veterinary Group in East Anglia, said strong vaccine uptake in that region had reduced the number of cases recorded so far this summer.

She argued that all sheep and breeding cattle, including bulls, should be vaccinated, and said her practice had administered thousands of doses without seeing side effects.