New cleaning process reduces hospital risk of vCJD

A new cleaning process can reduce the risk of hospital transmission of the human form of mad cow disease, scientists said on Wednesday.

Doctors have been concerned that variant Creutzfeldt-Jakob disease (vCJD) could be transmitted by contaminated surgical equipment, since standard sterilizing procedures do not destroy the abnormal prion proteins that cause the illness.

The new cleaning technique, which is described in the Journal of General Virology, could also be used to reduce infection risk from all forms of human prion diseases - progressive brain wasting illnesses for which there is no cure.

There is a particular concern about vCJD because the infectious prion is found in the lymphoid tissue of the body. Health officials fear it could be spread through surgical equipment used on the spleen or tonsils and through blood transfusions.

Unlike viruses and bacteria, prion proteins are resistant to high temperatures and stick very strongly to metal surfaces.

But researchers at the University of Edinburgh have devised a new technique to break these infectious particles down, using a high-energy form of gas called plasma.

"Our integrated strategy aims to provide a new approach to decontamination of surgical instruments and to ensure that decontamination is effective," Professor Robert Baxter, of the university's school of chemistry, said in a statement.

The system, which was funded by Britain's Department of Health, could be developed commercially, according to the researchers.

The surgical instruments are put in an oven-like container in which they are cleaned. The researchers envision it being used alongside other sterilizing techniques.

"This would work for any residue left on a surgical instrument," Dr. Helen Baxter, a member of the research team, said in an interview. "From what we can see, at the present moment, it cleans 1,000 times better than what we have in place," she added.

Since vCJD was first detected and linked to eating meat contaminated with mad cow disease, or bovine spongiform encephalopathy (BSE) in the mid-1990s, more than 150 people have died of the illness.

Earlier this year, scientists at Britain's Medical Research Council (MRC) developed a detergent to be used in large sterilizing machines in hospitals to destroy prion infectivity and cut the risk of vCJD infection though surgical instruments.