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MASSEY is published by Massey University, Private Bag 11-222, Palmerston North, New Zealand

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MASSEY has a circulation of 75,000.

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Catching The Plague

Professor Roger Morris is based in the Wool Building on Massey’s Palmerston North campus, but is seldom there. This corner office off a corridor with year after year of best fleeces on display under glass is not his natural habitat. Like the plagues he chases, he is a natural hopper of borders.

Tomorrow he is off again. His itinerary? “Hong Kong [where a student is studying human influenza] and then London, where I’m involved in a big international conference on geographical epidemiology at which we are giving most of the keynote papers, then I’m doing stuff on tuberculosis and foot and mouth and BSE, and then I’m going to Switzerland, where we have strong co-operative links.”

Morris is hot property, both academically and for the media, which knows him best as the scientist-pundit who has been able to foretell the fortunes of Britain’s foot and mouth disease epidemic with such uncanny accuracy.

How hot is Morris? “I had a friend in the US who did a search the other day and got 50-something pages of citations,” he says with a flicker of not displeased amusement.

The foot and mouth epidemic, which has cost the British taxpayer an estimated £2 billion, resulted in the slaughter of millions of livestock, and irrevocably changed the way the British see their countryside and farming industry, has proven the worth of EpiMAN, the animal and disease tracking software developed by Morris’ EpiCentre.

“At one stage a colleague was calling it our astrological model,” says Morris, “because we were saying the epidemic is going to break out in this area, and they’d go and look and find it. We modelled the disease and the disease was behaving exactly as we had modelled it.”

Only at the end of May, months into the epidemic, did the patterns begin to deviate. “So that raised alarm bells with us and we have gone back and in order to make the two come together we have had to assume a higher level of illegal movements from about the beginning of June than was the case earlier. There must have been this degree of undesirable movement taking place, over these kinds of distances, and these are the kinds of problems that could have arisen.”

Foot and mouth disease is the single most infectious disease known in any species, according to Morris, but it is far from the only disease in the animal epidemiologist’s Pandora’s box.

Seven other diseases also make the A list of the OIE, the world organisation for animal health. These are diseases that have “rapid spread, serious socio-economic or public health consequences, and major importance in international trade”. They include African horse sickness, Newcastle disease, contagious bovine pleuropneumonia, and sheep pox. All seven have had outbreaks in the last three years.

A further complication: the strain of foot and mouth ravaging Britain is itself one of seven strains. They are completely different diseases, but they produce the same, almost identical, signs, explains Morris, and each strain has multiple subtypes.

Then there is BSE (bovine spongiform encephalopathy), better known as mad cow disease, perhaps too recently emergent and not infectious enough to make the A list, but horrific in the manner in which its human expression – variant Creuzfeldt-Jakob disease (CJD)– kills those unfortunate enough to consume infected meat products: their brains become spongy masses of an abnormal protein. “BSE is spreading to more and more and countries because it spreads inside the infected animals and in feed unless people have the right control measures in force. We think there are going to be several more countries infected over the next five years,” says Morris.

Helen Benard of the EpiCentre, whose PhD in progress deals with BSE, points out that because the CJD disease incubation period is unknown, no one can even make an educated guess about how large the British CJD epidemic will be. Already it has claimed over 100 victims, “but we don’t know yet whether it will be a small or a large epidemic”. It is a disease-ridden world.

When Morris graduated as a vet from Sydney University in 1965, epidemiology – the study of the incidence and distribution of diseases – scarcely existed as a separate discipline. “I wanted to go to the US and get a PhD in epidemiology and there was only one university offering it – I never did get there,” says Morris. Instead he gained the multidisciplinary grounding that would serve him so well by doing honours papers: pure mathematics, economics and ecological systems analysis.

The new graduate had been immediately accepted into a teaching position, “which was quite unusual,” explains Morris, “but I was effectively working in a veterinary practice for the first 11 years, while teaching veterinary students at the University of Melbourne.

“I’d go out and calve a cow in the morning and then rush off to a maths lecture, and then back to calve the next cow, out of the overalls like superman. So I mixed economics, mathematics and clinical practice for several years while I was developing expertise in running a research programme.”

(Morris, who dresses in a business-like but slightly tweedy manner, still looks like he could don gloves and gumboots to deal with a cow in extremis.) Morris would eventually get his PhD from Reading University in Britain with a thesis on the use of epidemiological and economic studies of animal diseases.

The promise of a chair, funded by pharmaceutical company Schering-Plough, which would be free of the administrative chores of running a department, brought Morris to Massey. At the time Morris was the head of the department of clinical and population sciences (veterinary) at the University of Minnesota and the other job on offer was that of chief vet of Australia.

Fifteen years hence, and the EpiCentre has grown from three people to between 60 and 70, around half of them postgraduate students. Not all are resident at the centre, says Morris. “They come in for intensive sessions and then go back to their home bases, which could be anywhere from Hong Kong, to Botswana, to Palmerston North. And the other half are doing research on a range of projects or developing software.” Incidentally, Schering-Plough, which had initially promised five years’ funding, is still a major benefactor.

EpiMAN, the software package employed in Britain, is most obviously used to model the likely progress of an epidemic, suggesting ways of halting its progress. Alternatively, it can be used to trace an epidemic back to its likely source.

The conventional wisdom has been that BSE originated with scrapie, a similar disease in sheep, but Morris and EpiMAN have another suspect: a single antelope imported into one of Britain’s game parks in the 1970s.

“My view is that BSE is almost certainly a wildlife disease that has got into cattle. I have looked at 35 different theories. The top five are all wildlife-related, and the one that fits best is the antelope one. We know that this disease occurs in antelope – not naturally, but they are very susceptible to it in feed. One particular antelope that I have my eye on, the Greater Kudu, can transmit it.

“They are all bovids – cattle-like antelopes – and some of them, it appears, can transmit it from cow to calf, and some of them may be able to transmit it horizontally (from animal to animal).

“My theory is that out in the wilds of Africa this occurs naturally in one or more species of antelope.

“I know that antelope came into wild game parks in Britain. I know that some of those antelopes ended up in bone meal. I can’t prove it yet – and probably never will – that they carried BSE, but it’s the single best explanation.”

Working with 15 million cows and almost 200,000 cases of the disease, Morris modelled the disease spread.

“We can take one antelope-sized brain in 1973 and explain the epidemic. If we try to do the same with scrapie we can’t get the epidemic to behave correctly.”

If BSE leapt species in the 1970s, foot and mouth has an age-old pedigree. In the early 1850s there were 870,000 outbreaks of foot and mouth in Europe, and in Britain the disease was endemic. At the beginning of the twentieth century governments were persuaded to take radical action: isolating outbreaks, restricting the movement of livestock and blocking live imports. When outbreaks did occur they were dealt with by killing and burning stock, the ‘stamp it out’ policy maintained today in countries that are free of foot and mouth.

The strain of foot and mouth disease afflicting Britain emerged in the 1990s. “Most of us believe it came from China or somewhere in Asia,” says Morris “and it spread though India, Japan, South Korea, the Philippines and on to Taiwan, to South Africa, to Britain, Ireland, the Netherlands and France. It is a very successful virus.”

The British epidemic began in a piggery – a typical scenario, says Morris. “Infectious material gets into a piggery. The pigs multiply the virus enormously and breathe it out, then the cattle and sheep suck it in. Pigs almost always start the epidemic.”

An infected piggery can infect animals as much as 50 kilometres downwind. “The one good thing about this strain in Britain is that it is not a strain that goes particularly well in pigs. There have been very few pig farms infected, so it has spread mainly cattle to cattle or sheep to cattle,” says Morris.

Within days of the first diagnosis an invited team from the EpiCentre and MAF were on British soil. Morris was ensconced in Whitehall. Later on began the process of entering the details of every British farm, every nuance of the landscape, and every infected herd into the EpiMAN programme, making for the most complete inventory of the British countryside since the Domesday book.
Even now, at the end of each British working day the data from the epidemic is sent through to Massey to be processed during the New Zealand working day in time for the British morning.

(The British had bought EpiMAN in 1998, but matters such as BSE had intruded and it had never been fully deployed. The first planned exercise using the software – a swine fever epidemic simulation – was to have been held in September 2001.)

Pyres of burning animals, palls of smoke blackening the sky, near-military measures around farms, the widespread use of antiseptic foot and tyre baths and the closure of vast swathes of countryside, do not marry well with the popular Constable-landscape chocolate-box conception of Britain, nor does the wholesale slaughter of stock with the British soft-focus infatuation with animals. The measures used against foot and mouth caused widespread revulsion. Phoenix, the limpid-eyed calf reprieved from slaughter after a public outcry, may have represented a turning point.

Helen Benard, of the EpiCentre, went in with a New Zealand veterinary rescue team in early April. For three weeks she worked in a divisional office in Stafford. When a property was found to be infected – a death sentence for its livestock – she and her British colleagues would have to recommend which adjacent properties would have their stock slaughtered. On one occasion she was called out for a second opinion on whether the lesions on animals were foot and mouth.

“It’s not easy. If you are too soft, more animals will die than have to. It sounds terrible,” she says, embarrassed at her severity, “but you can’t be too soft.”

“So you are not too popular within the office: you are making these recommendations and other people are having to carry them out and sometimes not understanding the reasons why. Sometimes you would be openly criticised in the local newspapers as well.” ‘Misty the Goat Murdered by MAF’ was a not untypical local headline, run under an affecting photo of the late Misty herself.

Helen, though a veteran of responses to the Varoa bee mite outbreak in New Zealand and to an outbreak of classical swine fever in the Netherlands, found the British epidemic a dispiriting experience.

Would the ‘stamp it out policy’ be countenanced if there were another outbreak? Morris is candid: “I think it would be difficult to manage another major epidemic of this scale in the way that has been done, simply because of what people have seen and what has happened. The problem is that this is the best way of handling an epidemic of this nature.

“Our analysis shows that if they stopped slaughtering stock and started vaccinating there would have, by now, been about 6,000 farms infected and that the epidemic would probably have lasted five to 10 years.

“In Britain, on the day that this was diagnosed, there was one known abattoir infected and there were 29 unknown farms – as we now know. At the height of the epidemic, which was 27 March, there were 707 known infected farms and 342 unknown infected farms. The epidemic kept well ahead of them.

“We looked at every known alternative for using a vaccine and we could not see a way of checking the epidemic.

“When I am talking to colleagues in Thailand I hammer them with vaccination, vaccination, vaccination. That’s because the disease is endemic there. The only way we could have used the vaccine effectively would have been to say, ‘right the disease is endemic in the UK’, and that would have been much more damaging than what we call the stamping out policy.”

Morris dismisses the tempting notion that foot and mouth disease, BSE, swine fever and the other ills that have afflicted British farming of late can somehow be ascribed to some deeper malaise.

“The British farming system is not inherently worse. What has produced this is the globalisation of trade and the movement of people, animals and products around the world,” he says.

“The EEU in general and Britain in particular have said ‘we are committed to free trade’. On multiple occasions material has been brought in that has been responsible for these outbreaks.”

And what of New Zealand? We are, he says, the best prepared country in the world for an

emergency like foot and mouth. “We are very reliant on our trade, so we would take the necessary measures to deal with it. And we have strong border protection systems,” he says. But he sounds a caution: “The weakness that we have, and it concerns me greatly, is that the reason why you get big epidemics is that the disease is detected late. That’s what happened in the British foot and mouth epidemic, that’s what happened in the Netherlands with classical swine fever. Our surveillance systems for the detection of disease are not, I believe, up to the level they should be. So if we detected a disease late, we could also have a very serious and large-scale outbreak.”

Of course New Zealand itself is not free of serious endemic animal diseases. TB in cattle is one, the reservoir of infection being New Zealand’s many millions of possums. One of Morris’ ambitions is to arrive at a better way of controlling possum-transmitted TB.

Morris’ work has found that the last six weeks of a TB-infected possum’s life – when it is groggy and behaving erratically – are when it is most likely to be nosed by some curious cow. He found sick possums usually sleep in patches of scrubby bush. These can be identified by satellite, and by keeping cattle away from such areas in winter and summer, when the possums are at their most infectious, and by poisoning in autumn and spring, the risk of TB infection can be minimised. Not that this is good enough. More ingeniously, Morris has plans for a self-administered aerosol vaccine for possums, which will be attracted by a cinnamon scent.

Alert to the applications for such a technology, Morris talks of other instances where wildlife acts as a reservoir for disease and couldbe a candidate for self-vaccination: the badgers that carry TB, the foxes that carry rabies.

And that, for this interview, is it. There is that sense that Morris – epidemiologist, ecologist, veterinarian, raiser of venture capital, practised interview subject – really should be going. His attention has been unwavering, but other matters call.

“I actually have so much work I have subcontracted my university role to another epidemiologist,” he says. “I had so much international work I couldn’t cope otherwise.”

More than virus protection software...

“This is probably the biggest single software development group for animal health and production in the world,” says Morris, speaking of the EpiCentre Software Development Group. Eight software developers, a group manager and full-time software tester are employed developing software.

“We have a software company and we market software globally. We have software in everything from Chinese to Polish,” says Morris.

EpiMAN, which has been so effective in predicting the course of the foot and mouth epidemic, also has versions customised for TB and classical swine fever.

Other products in the complement of software are: PossPop: a geographical model that simulates the spread of tuberculosis in a possum population for a farm or user-defined areaDairyWIN: a day-to-day herd management programme for dairy farmers, veterinarians and farm advisersCowPAD: an add-on to DairyWIN that runs on a Palm Pilot, allowing farmers to enter and update herd data while in the fieldPigWin: pig production, management and monitoring software.

Disease Spread: a generic computer model of disease control in a national livestock population.

Under development is HandiRisk, a package for import risk analysis, and EpiMAN (Food Safety), for which Morris, in another of his roles, is looking for venture capital.

“We are working on a food-tracking system. We are working with a group of European co-operators. My colleague, Peter Davies is just in Europe at the moment working on a plan for a food safety management system to reduce the risks of food-borne disease. I am trying to put together a New Zealand end to the project, and a European end, and trying to get $10 to 15 million to invest in development and commercialisation in the hope that it will return several hundred million to NZ, because we are the world leaders in doing this kind of thing and I think we can claim our technology is the best in the world.”