- Scientists have found new evidence to
suggest that the human version of "mad cow" disease might be
transmitted during surgery via contaminated surgical instruments.
- A test for the new variant form of Creutzfeldt-Jakob
disease (nvCJD) shows the infectious agent responsible for the brain disorder
is present in tonsils and certain other tissues handled in thousands of
routine operations. Experts fear the nvCJD agent could survive the sterilisation
procedures for surgical instruments and bepassed from person to person
during hospital treatment.
- Government experts are drawing up a set
of new guidelines on the use of disposable scalpels, forceps and other
surgical instruments to limit the risks to patients. An anonymous mass
screening programme is also planned for later this year to detect people
- Thousands of tonsils are to be tested
at random over the next few years to try to determine how many in the general
population are infected with the human form of bovine spongiform encephalopathy
(BSE). At present there are 35 confirmed cases of nvCJD, which scientists
believe developed as a result of people eating beef contaminated with BSE,
but there are fears that this might be the first signs of an epidemic.
Attempts to estimate the future course of the disease have been hampered
by a lack of knowledge and a suitable test for early diagnosis.
- Professor John Collinge, a consultant
neurologist at the Imperial College School of Medicine at St Mary's hospital
in London, said yesterday he has developed a tonsil test for nvCJD which
will be used in the mass screening programme to diagnose the infectious
agent, believed to be a rogue "prion" protein. Previously, doctors
could only reliably confirm nvCJD with an examination of the brain after
death. "[The prion] is present in every tissue of every case of nvCJD
[we studied] and it's present at quite considerable levels," Professor
Collinge said. "This has implications for the risk of the infection
passing from one person to anothers. We don't know yet the level of infectiousness
in those tissues."
- This raised the prospect of using disposable
instruments wherever possible because "there is no means of sterilising
surgical instruments adequately against prions".
- Research funded by the Medical Research
Council and the Wellcome Trust, published in The Lancet, shows that although
the tonsil test could detect the infectious prion protein in nvCJD cases,
this was not the case for "classical" CJD. Professor Collinge
said this shows how the rogue prion protein behaves quite differently to
- Professor Liam Donaldson, the Chief Medical
Officer, said last night: "Current policy based on advice from the
Advisory Committee on Dangerous Pathogens published in April 1998 is that
when any patient with symptoms of nvCJD, or suspected of having nvCJD,
undergoes surgical operation, the instruments must be removed so that they
cannot be used again."
- How many more will die?