'This is a new disease and we are entering the unknown' Britain may still harbour CJD timebomb, warns professor

BSE INFECTION: Three decades may be needed for incubation period of the disorder that has claimed 53 lives and could yet kill thousands more

Thousands of people could be incubating variant Creutzfeldt-Jakob Disease (v-CJD) as a result of eating infected beef in the 1980s, say scientists, but it may take decades before the effects are clear. We may not even know what has happened until any epidemic is almost upon us.

"I draw comparisons with kuru, which affected cannibals in the Pacific," said Professor John Collinge, an expert in v-CJD and BSE at the neurogenetics unit of St Mary's Med- ical School in London. "There we saw long incubation periods of decades. Put on to that a species barrier from cows to humans, which prolongs the incubation period, and you would probably expect an average incubation period of 20 to 30 years."

He thinks that it is easy to draw the wrong conclusion from the two years of tests on 3,000 appendixes and tonsils from hospitals in Lanarkshire in Scotland, and the south-west of England. Those found none with the "infective" prion protein (a misshapen form of the body's own PrP protein, found in cells). By contrast, prions have been found in all of the 53 Britons who have so far died of the incurable brain disorder.

The tonsils and appendix are part of the body's lymphatic tissue, which has been shown to accumulate prions before the brain is affected. This study should thus offer some insight into how many people may be harbouring the incurable illness. "We knew those studies, though necessary, could produce no news or bad news," said Professor Collinge. "This result is no news."

Dr Sheila Bird, a medical statistician who has followed the epidemic's progress, said just one positive sample in the 3,000 would imply there were thousands of people incubating the disease. But if the prevalence is one in 100,000, scientists would not expect to find any in the 3,000. But that doesn't mean it isn't out there.

Another 15,000 tests are planned for tonsils and appendixes removed between 1996 and 1998, which will take a further two years, while tests on 2,000 "fresh" samples are also being carried out. But even those are too small to give a definite picture of how many might be incubating the illness

With v-CJD, the unknowns multiply endlessly. How long is the incubation period? It may be five years, or 20 years. (It could be both.) It may be that only people with a particular genetic make-up (shared by 40 per cent of the population) are susceptible, as all the victims have that genetic make-up - or it might be that people with that genetic composition (a tiny variation of one amino acid in the huge PrP protein) develop the disease more quickly.

Ever since Stephen Dorrell, then the Secretary of State for Health, told Parliament in March 1996 that there appeared to be a link between BSE and v-CJD, people have wanted to know what the eventual figure would be. Professor Richard Lacey predicted in the 1980s that millions of people would die of CJD - a prediction that shows no signs of coming true. In 1997 two British scientists, Dr Peter Smith - now a member of the government's advisory body on BSE and v-CJD - and Peter Cousens tried to estimate the eventual number of v-CJD cases, based on the data from 14 cases.

Their worst-case prediction was 80,000, and their mid-range predictions between 1,000 and 10,000, spread over the next 30 years. The incubation period - between eating infected food and developing the disease - was estimated at 10 to 25 years.

Since then, no data has emerged to make those predictions look less accurate. Dr Graham Medley, an expert on CJD from Warwick University, said yesterday: "We still know very little about how long people carry CJD before they develop it, and it is therefore difficult to know what the scale of the threat is. If the incubation period is ten years, then we are in the middle of the epidemic. If it's 30 years, then we are only at the beginning. We have never seen this disease in humans and we simply do not know."

Start your day with The Independent, sign up for daily news emails
Have you tried new the Independent Digital Edition apps?
ebooksA special investigation by Andy McSmith
  • Get to the point
2015 General Election

Poll of Polls

Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Experienced Bookkeeper - German Speaking - Part Time

£23000 - £25000 per annum: Recruitment Genius: This firm of accountants based ...

Recruitment Genius: Operations Manager

£30000 - £38000 per annum: Recruitment Genius: They are a financial services c...

Ashdown Group: Field Service Engineer

£30000 - £32000 per annum + car allowance and on call: Ashdown Group: A succes...

Recruitment Genius: Sales & Marketing Co-Ordinator

£15000 - £17000 per annum: Recruitment Genius: Well established small company ...

Day In a Page

Robert Fisk in Abu Dhabi: The acceptable face of the Emirates

The acceptable face of the Emirates

Has Abu Dhabi found a way to blend petrodollars with principles, asks Robert Fisk
Nepal earthquake: One man's desperate escape from Everest base camp after the disaster

Escape from Everest base camp

Nick Talbot was sitting in his tent when the tsunami of snow and rock hit. He was lucky to live, unlike his climbing partner just feet away...
Adopting high fibre diet could dramatically cut risk of bowel cancer, says study

What happened when 20 Americans swapped diets with 20 Africans?

Innovative study in the US produces remarkable results
Blake Lively and 'The Age of Adaline': Gossip Girl comes
of age

Gossip girl comes of age

Blake Lively is best known for playing an affluent teenager. Her role as a woman who is trapped forever at 29 is a greater challenge
Goat cuisine: Kid meat is coming to Ocado

Goat cuisine

It's loved by chefs, ethical, low in fat and delicious. So, will kid meat give lamb a run for its money?
14 best coat hooks

Hang on: 14 best coat hooks

Set the tone for the rest of your house with a stylish and functional coat rack in the hallway
Not even the 'putrid throat' could stop the Ross Poldark swoon-fest'

Not even the 'putrid throat' could stop the Ross Poldark swoon-fest'

How a costume drama became a Sunday night staple
Miliband promises no stamp duty for first-time buyers as he pushes Tories on housing

Miliband promises no stamp duty for first-time buyers

Labour leader pushes Tories on housing
Aviation history is littered with grand failures - from the the Bristol Brabazon to Concorde - but what went wrong with the SuperJumbo?

Aviation history is littered with grand failures

But what went wrong with the SuperJumbo?
Fear of Putin, Islamists and immigration is giving rise to a new generation of Soviet-style 'iron curtains' right across Europe

Fortress Europe?

Fear of Putin, Islamists and immigration is giving rise to a new generation of 'iron curtains'
Never mind what you're wearing, it's what you're reclining on

Never mind what you're wearing

It's what you're reclining on that matters
General Election 2015: Chuka Umunna on the benefits of immigration, humility – and his leader Ed Miliband

Chuka Umunna: A virus of racism runs through Ukip

The shadow business secretary on the benefits of immigration, humility – and his leader Ed Miliband
Yemen crisis: This exotic war will soon become Europe's problem

Yemen's exotic war will soon affect Europe

Terrorism and boatloads of desperate migrants will be the outcome of the Saudi air campaign, says Patrick Cockburn
Marginal Streets project aims to document voters in the run-up to the General Election

Marginal Streets project documents voters

Independent photographers Joseph Fox and Orlando Gili are uploading two portraits of constituents to their website for each day of the campaign
Game of Thrones: Visit the real-life kingdom of Westeros to see where violent history ends and telly tourism begins

The real-life kingdom of Westeros

Is there something a little uncomfortable about Game of Thrones shooting in Northern Ireland?