Need to get past the media hysteria

LET'S get real here, folks. There is very little if any chance that you will come down with Mad Cow Disease after tacking into a tasty Tbone or munching through a burger.

No scientist researching bovine spongiform encephalopathy (BSE) has yet said that you will get BSE, or more specifically its human equivalent, Creutzfeldt Jakob Disease (CJD), if you eat beef. Nor have they established that eating the maddest of mad cattle poses a risk to humans at all, bar the danger of consuming too much animal fat increasing your risk of heart disease.

You are more likely to be injured by upset consumers stampeding away from a supermarket meat counter than by eating beef - and this goes for Irish or British beef, BSE notwithstanding. And yet people have come to believe there is a risk, with media and consumer fears creating a biofeedback approaching public hysteria.

Not only do we have to be wary of steak. Beef cubes and Easter eggs held together with gelatine are also now suspect and viewed as a potential way to commit suicide.

The current BSE scare is a wonderful example, of how we sometimes fail to distinguish between an actual quantifiable risk and our perception of that risk. We can distort out of all proportion meaningless risks, responding to them as thought they were a real danger, and can blithely ignore others that are a proven and undoubted risk.

Think about it. There are people, who are happy to strap a giant kite on their backs and jump off cliffs - they call it hang gliding. But insurance actuaries put people like that right up there with war reporters, trapeze artists and steeplejacks when calculating risk, yet no one is going to ban hang gliding.

We got very exercised when Chernobyl radiation reached our shores in 1986, and rightly so we have no nuclear industry and we felt we had been put at risk by this tradition, to which we will all be exposed for the rest of our lives. But our entire lifetime radiation exposure because of Chernobyl is about equivalent to that involved in a flight to New York.

Scientists never discount a risk, because the next discovery is always just around the corner. They usually say "as far as can be established" or "no known link" in such circumstances, until the weight of new research proves it right or wrong.

So while no one absolutely rules out the BSE CJD link, there is nothing - so far - to suggest that the link exists.

BSE was identified in 1986. Scientists quickly established that it most likely came into being when scrapie, a disease in sheep, crossed, the species barrier after infected sheep offal was reprocessed and fed to cattle as a food source. They have since been able to infect a range of animals by feeding BSE infected meat, showing that the disease can move across the species barrier.

There was an immediate focus on the risk of BSE transfer to humans, given the food processors willingness to feed us offal, brains and other materials known in the beef trade as the "fifth quarter". So far, the crossover to humans has not been shown to occur.

In this context we should remember that Ireland has BSE. We keep being told that Britain has much more, but yet the fact remains, we are a BSE nation. Depending one how you present the statistics, it is possible to say that Ireland has the third highest BSE infection rate in the world behind the UK and Switzerland. Ours is 1,320 times lower than the UK rate, but then ours is 123 times higher than Canada's rate. It follows that if BSE is a risk factor in CJD infection, then there is an associated higher risk of CJD here because of BSE.

If BSE is a new source of CJD infection in humans, then we should be able to find evidence for this in the numbers of cases presenting in Ireland or Britain, given our predilection for beef. On average we have two servings of beef a week, about 18 kg a year per man, woman and child, marginally more than in the UK.

But these CJD cases do not seem to appear in the public health record according to Dr Mark Rogers, a CJD specialist at University College, Dublin.

There is a very slight increase in CJD in recent years in Britain he says, but does that reflect more rigorous reporting and investigation on the disease becoming more common?

In this context it is worth looking at the German and Austrian experience. These countries effectively have no BSE cases, but they still" have the expected levels of CJD.

As to other perceived as opposed to actual risks, the Department of Health estimates that 7,000 people, die each year because of smoking related illnesses. No one legislates to ban smoking - it is a personal lifestyle choice - but these deaths represent 2,000 years of CJD, deaths.

There were just over 14,000 deaths due to heart disease here during 1994, including heart attack, stroke and cardiovascular disease. This represents 45 per cent of all deaths by any cause, yet no one is planning to legislate to force people to exercise, adopt a healthier diet and give up smoking, which would prevent many of these deaths.