vaccine to control the spread of sheep scab
is a step closer, following a major breakthrough
by researchers at the University of Leeds.
The research is part of a multi-million pound
DEFRA-funded national programme to reduce
the use of dangerous chemicals by farmers.
Dr Alison Lee and Professor Elwyn Isaac have
identified and isolated a protein from the
sheep scab mite (pictured above) which
triggers the sheeps immune responses,
protecting it from infestations. The protein
could be used to form the basis of a vaccine
against sheep scab.
Dr Lee said: Sheep scab is currently
treated with the application of organophosphates,
but there is widespread concern over the risks
these chemicals pose to agricultural workers,
to consumers who eat the meat, and to the
environment when chemicals enter the water
table. There are also worries that the mites
which cause the disease will become resistant.
A vaccine is a more sustainable option, and
could be more cost effective for the farmer.
Sheep scab was eradicated in the UK in 1952,
but was reintroduced from Ireland in the 1970s
and is now endemic in UK sheep flocks. Cases
of sheep scab are increasing and outbreaks
are reported in all parts of the UK. The disease
is highly contagious, and causes extreme discomfort
to the animal, which will scratch infected
areas against fences or walls, often opening
up wounds which can lead to potentially fatal
The researchers from the school of biology
have been working with scientists at The Moredun
Research Institute in Edinburgh, the Veterinary
Laboratory Agency and the University of Aberdeen
to develop an alternative non-chemical method
to control the disease, with the aim of developing
a strategy such as a vaccine that could offer
long-term protection without any danger to
operators or the environment. They now plan
to use the protein in vaccine trials and to
develop a test for the early diagnosis of
sheep scab infections.