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YOU just couldn’t make it up. Government scientists spend four years
painstakingly injecting hundreds of mice with the remains of thousands of sheep
brains in a bid to resolve the biggest unanswered question of the BSE
crisis—whether British lamb was infected along with beef. Preliminary
findings indicate some evidence of BSE. Ministers, fearing the worst, draw up
contingency plans to slaughter the entire flock. Then, the bombshell. The brains
being tested are not from sheep at all. They are from cows.

Even hardened chroniclers of the myriad scientific cock-ups and cover-ups of
Britain’s BSE years were stunned last week by the latest blunder—and the
government’s apparent attempt to bury the news in an obscure press statement
released late on Wednesday night. Supposedly definitive experiments that cost
the nation’s taxpayers £217,000 are now worthless. The bottom line is that
14 years after the first confirmed BSE case in British cattle, scientists are no
closer to knowing whether the infectious agent passed into sheep. And with no
proof lamb is safe, consumer groups want it banned in baby food.

Yet again the government is in a fix over BSE. The timing couldn’t be worse.
It’s a year ago to the week since the publication of the Phillips report, a
massive 16-volume investigation into BSE designed to end exactly this sort of
mistake. The result of a harrowing four-year public inquiry costing £27
million, the report attempted to trace and catalogue every last blunder and
error of judgement that led scientists to downplay the BSE risk—and
government ministers to coolly insist it didn’t exist.

Trust the public

The secretive, accident-prone culture of Whitehall must go, it concluded. And
in its place must come a new era of transparent policy making in which risks of
all kinds are spelled out, uncertainties acknowledged and scientists speak
openly about experiments of public importance. On BSE and vCJD, the human form
that has claimed 107 victims, there must be a vigorous scientific assault to
answer all remaining concerns. Was the agent lurking in sheep? Was it in soil?
Were existing controls sufficient to prevent the nightmare recurring? Britons
should be told.

Since then things haven’t exactly gone to plan. The government faces charges
of dithering and incompetence over its handling of the foot and mouth crisis.
And on BSE scientific progress has been painfully slow. Scientists still cannot
say why the disease continues to surface in calves born after 1996, when the ban
on meat and bonemeal was strengthened to close off all possible routes to cattle
feed. Nor can they prove the agent doesn’t lurk in soil.

Worse, the Phillips inquiry itself now stands accused of misleading people
about an area of BSE science crucial to preventing a repeat epidemic.

Until last year, most BSE researchers believed the disease originated in
sheep as a rare mutant version of the prion protein that causes the similar but
much older sheep disease scrapie. The Phillips report ripped up that script and
claimed BSE arose instead in one lone cow sometime in the 1970s, courtesy of a
freak mutation that turned the cow’s own prion proteins into the rogue form that
causes BSE. In hindsight, said Phillips, not only were government scientists
wrong to assume BSE was harmless because it was a form of scrapie—they
were wrong about the sheep link altogether. Then, in July this year, a second
panel of experts implied that Phillips had got it spectacularly wrong, not the
BSE scientists
(see “Full circle”).

Instead of entering the sunlit uplands of transparent policy making and clear
science, we seem to be going back to the bad old days of confusion and discord.
What’s going on?

The experiments at the centre of the latest blunder were carried out by Chris
Bostock and his team at the Institute for Animal Health in Compton, Berkshire.
The aim was to look for signs of BSE in liquefied brain tissue from sheep which
died of scrapie in the early 1990s, when BSE was at its height.

To find out if the brains contained BSE, the team injected samples into mice
specially bred for distinguishing BSE from other prion diseases, including
scrapie. How long such mice survive reveals which disease they’ve been injected
with. But last week, the whole experiment fell apart when government scientists
tested three samples of tissue used in the experiments and could find only cow
brain, not sheep. “The results are unequivocal,” says Helen Parkes at the LGC,
formerly the Laboratory of the Government Chemist, who carried out the
tests.

How could this happen? Our inquiries reveal that British veterinary officials
certainly collected 2867 brains from scrapie-infected sheep between 1990 and
1992. But at around the same time, in 1990, they also collected 861 brains from
BSE-infected cows. All the brains were placed in polythene bags and made
available to a team of scientists headed by David Taylor of the government’s
Institute for Animal Health in Edinburgh. The scientists wanted to find out if
the scrapie prions inside the sheep brains—and the BSE prions inside the
cow brains—could survive rendering, the process used by animal feed
manufacturers to turn animal remains into meat and bonemeal.

The results of the cow and sheep studies appeared in separate papers in the
Veterinary Record (vol 137, p 605; vol 141, p 643)—from which it’s clear
that the sheep brains were processed in exactly the same way as the cow brains
and in the same premises.

In both cases, the brains were stored in a freezer, warmed up, minced and
eventually poured into six sterilised plastic dustbins. Some was decanted into
polythene bags for the rendering experiments, and 10-gram samples were set aside
for other tests.

The most disturbing possibility is that material from the six bins of cow
brains got mixed up with the six bins of sheep brains. This could make all
subsequent experiments based on material from these brain pools worthless. Or
perhaps only certain samples drawn from the two pools got muddled up or
mislabelled, including ones used in the all-important experiments looking for
BSE in sheep.

What is clear is that nobody spotted the mix-up until it was too late. Even
though Bostock and his team suspected the samples might have been contaminated
with cow brains, the scientists did not screen for the presence of cow genes or
proteins in the material before they began their studies. In fact, it wasn’t
until last year that the team asked the government’s Veterinary Laboratories
Agency in Weybridge, Surrey, to test the material. When the VLA found no cow
material at all, the doomed mouse experiments continued. Now, astonishingly, we
learn that the VLA team tested the wrong brains. They screened their own stored
material, not that used in the mouse experiments.

Scientists who carried out the flawed experiments are blaming government
officials for insisting that they use the suspect material. Elliot Morley,
Britain’s minister for animal health, in turn blames the scientists, saying they
should have checked the material at the start. As two inquiries into the
incident get under way, everyone is pointing the finger at everyone else and no
one seems willing to accept responsibility.

Despite the Phillips report, obfuscating cobwebs are clearly still hanging in
the corridors of British government science. If further evidence is needed, say
critics, look at how the government handled foot and mouth. Indeed, one
prominent scientist told us that if channels of communication within Whitehall
were as free as Phillips wanted, the foot and mouth virus should never have
reached Britain in the first place.

“We’ve known about this strain of virus for about a decade,” says Hugh
Pennington, professor of microbiology at the University of Aberdeen and chairman
of an inquiry five years ago into a fatal outbreak of food poisoning in
Scotland. Tragically, though, the threat it posed never filtered through to
Whitehall from virologists at the Institute for Animal Health in Pirbright. As a
result, there was never any tightening up of animal security at airports and no
push to curb escalating sheep movement within Britain.

Nor, so far, has there been much of an effort to strengthen Britain’s network
for monitoring infectious animal diseases—the linchpin for future
preparedness. “The Phillips inquiry recommended there should be more emphasis on
epidemiology, and all of this has been disregarded,” says Roger Morris, an
epidemiologist at Massey University in New Zealand. “It’s still relatively badly
supported in the UK.”

The government did at least heed Phillips’s advice to put a senior scientist
in charge of the show and consult more independent experts—two things
lacking in the battle against BSE. Unfortunately, many of the experts the
government consulted were unfamiliar with animal diseases. “I have grave concern
about whether all the scientists best qualified to give advice were being
brought into the loop,” says Pennington. “The [vets and virologists] at
Pirbright weren’t really being listened to.”

This time it’s different

Worse, too much modelling and forecasting was based on what happened during
Britain’s last foot and mouth epidemic in 1967, says Malcolm Ferguson-Smith, the
scientist who helped Phillips draft his mammoth report. That outbreak involved a
totally different strain of the virus. So when it came to deciding how best to
control the disease—via culling, vaccination or a combination of the
two—more emphasis should have been placed on outbreaks in other countries
involving the new strain, says Ferguson-Smith.

And the thinking, say some, was far from transparent. “We haven’t seen the
assumptions behind the models,” complains Erik Millstone, a veteran policy
watcher at Sussex University’s Science Policy Research Unit.

The government rejects this. Morley insists the decision not to vaccinate was
“rigorously based on science” that has been put in the public domain. He also
blames farmers—not officials—for the delays that let the virus
spread. If farmers hadn’t challenged in court the government’s right to carry
out its strict culling policy, he says, the crisis would have been dealt with
more swiftly.

Perhaps. The trouble is that whoever is right, we may not now get a chance to
hear all the arguments in full. The Phillips inquiry was open to the public and
concluded that without further openness the ghost of BSE would never be
exorcised. The new inquiry into foot and mouth disease is being held by three
different committees.

All in private.