Blinded by the funeral pyres
BY MAGNUS LINKLATER November 6th 2001 The Times
The Government is to speed up the slaughter of animals at risk of foot-and-mouth disease and claims that vaccination does not work. Ministers refuse to see the truth
The Government still believes in mass slaughter. Last week, an Animal Health (Amendment) Bill that gives the authorities greater powers to authorise swifter culling of animals simply because they risk spreading foot-and-mouth disease (FMD) was published in the House of Commons. Ministers want to stop farmers pursuing legal action, which delayed the slaughter of cattle and sheep. Under the new proposals, farmers will be denied the right to appeal against a decision to cull, and state vets and slaughtermen will have powers of entry to carry out slaughter. Controversially, pets and zoo animals will be included.
If the disease flares up again, the killing, it seems, will simply recommence, but at a faster rate. Yet none of the various inquiries into FMD has been completed to show whether the Government's stance is justified. If anything, the Government's resistance to new thinking has hardened. Last month, the Department for Food and Rural Affairs (Defra) published a weighty document signed by its junior minister, Elliot Morley, that dismisses vaccination as a means of bringing FMD under control. On scientific, practical and economic grounds, Morley says flatly that vaccination would not work.
It is one of the most depressing government documents that I have read. It concludes, in effect, that the policy of mass slaughter, the millions of animals killed, the smoking pyres that have blighted the countryside, the body-blow inflicted on tourism, and the lingering after-effects of empty fields and abandoned farmyards is the method Britain prefers in dealing with FMD.
The bleak conclusion is that we have made little or no advance in how best to tackle the problem. In effect, science has stood still.
And yet this document, which stands as the Government's verdict on FMD, raises as many questions as it answers. It is full of selective arguments, half-truths, poor science and flawed logic. Above all, it simply fails to address whether Britain, unlike almost every other country that has had the disease, has learnt anything from the outbreak.
Now, with FMD petering out - largely because, as happens with many epidemics, it is approaching the end of its natural cycle - Professor David King, the Government's chief scientific adviser, proclaims that Britain's slaughter policy has been a success - all at a cost of billions of pounds, and after a nine-month nightmare that has brought parts of our countryside to their knees.
Whether the various inquiries that have been launched into the epidemic will reach the same conclusion remains to be seen. But the notion that Morley's thoughts on FMD can be allowed to stand as the last word on the world's worst outbreak is simply absurd.
He makes a number of highly contentious claims:
Vaccination does not remove the virus
No one has ever suggested that it does. What vaccination does, as Morley should know, is to immunise the susceptible population. Throughout the world vaccination has been used, in animals and in human beings, to combat disease, limit its symptoms, and eventually eliminate it. There is no reason why the same should not be true of FMD, now that the strain has been identified.
Nationwide mass vaccination does not stop the disease spreading from generation to generation This is simply nonsense, and is based on a misunderstanding of what vaccination might achieve. If 80 per cent of a herd or flock is vaccinated, it will create herd immunity by reducing the number of susceptible animals to such a low point that the virus has nowhere to go. The wild type of virus may remain for a time in grass and damp soil, but
then it, too, will die out. In Argentina, which has mass vaccination, there is no evidence that the disease is passed on from generation to generation. It recurred only as a result of cross-border infection.
Vaccination would make it impossible to tell when natural infection with the virus is present Untrue. If Morley had been up with the latest research, he would have been aware that there is a convenient and reliable way of distinguishing between antibodies from infected and vaccinated animals. The June issue of The Journal of the Royal Society of Medicine carries an article explaining how it is done by using an enzyme-linked immunosothent assay (Elisa) for antibodies, which will distinguish between infected and vaccinated animals. The same article disputes another of Defra's claims, that infected vaccinated animals can become carriers and thus transmit the infection. The risk, it says, is very low.
Vaccination on its own would not eradicate the disease
No one suggests that it would. "Ring" vaccination around a new outbreak, and removal of the infected herd only, would mean that contact animals would cease to be a worry. Slaughter, vaccination and bio-security would continue to be used. Herds with overt signs of the disease would be slaughtered, but that would be a relatively small number.
Current policy in Europe demands that vaccinated animals should also be slaughtered. However, even this approach is now being challenged by more enlightened countries, such as The Netherlands.
Immunity declines after about six months The newer vaccines are good for at least a year and probably for longer, but even six months would be adequate as a measure to reduce the infectious load in the environment and rapidly to damp down the epidemic. Since an epidemic can be expected to be brought under control and the disease eliminated within two to three weeks of the start of a wholesale vaccination programme (two months at most), by the time the immunity conferred actually wears off, there will be no virus around to challenge the animals. Morley's point is, therefore, irrelevant.
Vaccination does not necessarily protect against infection, so vaccinated animals can still spread the disease An overstated problem, since there is evidence that they only spread at less than 15 per cent of an unvaccinated animal's rate, and only to unvaccinated animals in the same air space; vaccines prevent the huge contamination of the environment, people, vehicles and milk - and thereby reduce the spread from farm to farm.
There are two reasons to vaccinate any population, animal or human: first, to protect individuals against clinical disease; and, secondly, to protect others in the population against risk. Measles vaccine, for instance, protects the individual against potential serious illness. Rubella vaccine (German measles) protects the population against circulating the "wild type" , which is a risk only to pregnant mothers or, strictly, the developing child.
Vaccination does not protect animals that are already incubating the disease at the time of infection, but this is a very small number and one that would diminish rapidly once a vaccination programme started.
Vaccination will not always work To which the answer is: neither, self-evidently, does slaughter. But vaccination does not lead to mass killing, nor does it ruin the tourist trade, nor is it as unethical and crude as the present policy. While vaccination may not always work in respect of all individual animals, it always works in relation to disease control.
Ruminant animals exposed to FMD can become persistently infected with the virus Some ruminant animals do indeed become persistent carriers, but their level of infectivity is extremely low - it has never been possible under controlled conditions to demonstrate infectivity and there has been no evidence of field transmission. Furthermore, if vaccination is applied, fewer animals over a shorter period will be exposed to the disease (because it will be brought under control that much more quickly), so the overall number of carriers will be reduced significantly. In that context, vaccination reduces the number of animals that will become carriers.
There is no way of distinguishing between infected and vaccinated animals Not true. You can test a herd for virus excretion with modern technology. Unfortunately, Defra has consistently prevented independent virologists from developing it, and refuses to use the method itself. One of the most serious criticisms levelled against the department is that it has shown no interest in theories or technology that contradict its prejudices.
Vaccination will not prevent an animal from becoming a carrier The evidence is that vaccinated animals that become infected from "heavy-load" exposure do not become infectious carriers, and do not become clinically ill. They may produce virus, but it is coated with antibody and is not infectious. Morley repeats the argument that vaccination would remove Britain's FMD-free status and destroy our export trade. But the value of our export trade pales in comparison with the current cost of combating FMD.
Even if the present epidemic is pronounced over by the end of the year, at least three more months will have to be added before export status is returned. If vaccination had been carried out last March, the epidemic would have been over by April/May and we would be getting our export status back in April/May 2002. Millions of animals would have been spared and the countryside would have been back to normal for last summer season, saving millions of pounds.
In The Netherlands, where vaccination was used on a small outbreak, the disease has been eradicated, and exports resumed. Morley counters this by saying that the Dutch had to slaughter all their vaccinated animals. That is true, but only because EU legislation insisted on it. LaurenJan Brinkhorst, the Dutch Minister of Agriculture, is convinced that the slaughter was unnecessary and is pressing for change.
Rather than adopting Britain's blinkered approach, he has learnt from experience and is determined to introduce a more enlightened policy.
In Argentina, whose 52 million cattle are vaccinated on a regular basis, slaughter is never used. Yet the nation exports 50 to 60 per cent of its beef, and regards Britain's approach as expensive and unnecessary. Argentina achieved FMD-free status in 1998, and has been reinfected only because of cross-border traffic. Vaccination is "a way of life".
All of this evidence is real, practical and current. It is the kind of first-hand data that should be generating debate, moving the argument forward and advancing our knowledge of this damaging disease.
Yet the men from Defra seem to be as deaf as its initials suggest. The only language they seem to understand is the language of death