HC Deb 11 April 1984 vol 58 cc503-8

Motion made, and Question proposed, That this House do now adjourn.—[Mr. Garel-Jones.]

11.42 pm
Mr. Colin Shepherd (Hereford)

I am very grateful to my hon. Friend the Parliamentary Secretary for coming to the House this evening to discuss the—to me—very interesting subject of leptospirosis, and cattle-associated leptospirosis in particular. We can both heave a sigh of relief that we are here at a modest hour and not early in the morning, as has been the case of late.

My hon. Friend will know that among the many important functions—and there are many—which go on in Hereford, the Public Health Laboratory Service has its leptospirosis reference unit. It is very much as a consequence of the work done by that unit, and by Dr. Sheena Waitkins in particular, that I have sought to utilise this opportunity to draw attention to the concern which should be shown in the dairy sector of the farming community in respect of one particular strain of leptospirosis—cattle-associated leptospirosis.

In this matter the interface between this House and departmental responsibility is complex. The disease is one which affects cattle, with associated problems of cattle suffering abortion and milk loss, together with financial loss for farmers. It is also capable of being easily transmitted to man. The evidence points to a greater level of infection than was previously apparent.

My purpose in drawing attention to the various interrelated problems is, first, to increase agricultural awareness of the disease; secondly to increase medical awareness of the condition; and, thirdly to sound out my hon. Friend—who is the Minister with particular responsibility for animal health matters—on the possibility of developing a programme of containment of the disease at source, that is to say, to deal with before it leaves the infected cattle.

I raised the matter with my hon. Friend the Parliamentary Under-Secretary of State for Health and Social Security, who gave me a somewhat disappointing reply on 27 March. He said that he was satisfied that GPs have an adequate knowledge of the risks of the disease, especially in dairying areas."—[Offical Report, 27 March 1984; Vol. 57, c. 133.] My hon. Friend the Parliamentary Secretary has no responsibility for the replies of a Minister in another Department, and I would not ask her to comment on that reply. It is worthwhile noting, however, that the disease is being discovered by those medical practitioners who have become attuned to look for cattle-associated leptospirosis. Other doctors may mistake it for flu.

One Herefordshire milk producer, with a herd of 130 milkers, contracted human leptospirosis or CAL. His herd became infected in 1982, and he contracted the disease. He became very poorly. Because the illness was not like ordinary flu, his wife called in the doctor. The doctor said that it was a bad case of flu. He said, "It's just a case of sweating it out." The next day, the cowman went down with the disease and a standby cowman was called in to help with the milking. Four days later, the standby cowman, too, fell ill. Because of the dairy connection, his doctor, who lived in Hereford, suspected brucellosis, and treated him with penicillin. Because penicillin deals with CAL as well as brucellosis, the cowman recovered speedily. When his blood sample was sent to the reference unit and showed leptospirosis, Dr. Waitkins became aware of the problem. She went out to the farm, took blood samples and found that the producer and his cowman had the same problem. A few days later, after taking tablets and penicillin, they had begun to recover.

That milk producer said, I have never had anything like it before. The NFU and the farmworkers' union should press for urgent research into this disease, and if eradication is shown to be possible then they should be supported to the hilt. He had had a blinding headache, worse than anything he had ever known before. It was so bad that he could not bear to touch a single hair. He was miserably feverish—hot and cold—and poured sweat in torrents to no avail. One can understand his sentiments. Two years later, he still has to wear a woolly hat to keep his head warm, and so does his cowman.

Today, when the dairy industry is under severe pressure, it is relevant that the economic losses which the disease can cause are also severe. One farmer in the Welsh borders with 250 cows lost some £11,000 in 18 months in 1980 and 1981. That was accounted for by 21 dead calves, half the normal milk yield from 10 cows that calved early, replacements for two dead cows which had developed chills while ill, lactation loss from 80 cows—the average loss being two and a half litres for 150 days—and milk from 80 cows held back for three days following antibiotic treatment.

Another producer near Ludlow recently aggregated the losses that he had suffered at about £15,000 on his herd of 230 cows. Such losses are in no way inconsequential.

A logical progression from the human and economic factors that I have outlined must take one to the conclusion that prevention is better than cure. But one might ask whether there is in fact a real problem to prevent.

As brucellosis recedes into the past because of the extremely successful eradication of the problem, the wider extent of the human aspect of CAL is becoming more apparent. It has certainly been cloaked before. In a recent written answer I was told: The increase in cattle-associated infections"— of leptospirosis— in 1983 is thought to be due largely to increased awareness of the disease in the farming community and not to an increase in the disease in herds."—[Official Report, 20 March 1984; Vol, 56, c. 424.] So far, so good, but the work done by Dr. Waitkins of the leptospirosis reference unit points to the probability that at least one third of Britain's dairy herds are infected or show serological evidence of past infection. That shows that the problem could be far more serious than has hitherto been appreciated. In economic terms, that means that one third of dairy farmers will at some time stand to lose a lot of money. There seems to be an incipient problem which, if the experience of New Zealand is anything to go by, could increase. The rate of infection there is 90 per cent., and climatic conditions are not dissimilar to ours.

Our Herefordshire milk producer who suffered asked for urgent action. In New Zealand it was the farmers' wives who showed the greatest anxiety. It was the women's division of the New Zealand Federated Farmers, the equivalent of the women's section of the National Farmers Union, which built up the pressure for action. Action is being taken and vaccination is becoming much more frequent. Indeed, as many as 50 per cent. of cows in New Zealand are now vaccinated. Hitherto, vaccines have not been available in the United Kingdom although they have been made here. I am given to understand, however, that vaccines are now available for British herds. That is encouraging news. I do not want to pre-empt anything that my hon. Friend the Minister might want to say, but, as Dr. Waitkins put it: Once there is a vaccine for animals then the human problem should be reduced. Whilst vaccines don't totally eracicate leptospira, treated cows become such low rate shedders that their urine does not contain enough bacteria for humans to be at risk. New Zealand is well ahead of the United Kingdom in the war against leptospirosis—as it should be with its 480 cases in humans which are notified each year. Although we have so far examined only the tip of the iceberg with our 40 cases last year and 100 cases in the past six years, it is probable that there are many more unnoticed and therefore unnotified cases. I do not want our problem to grow to the level of New Zealand's. I am therefore asking my hon. Friend to do all that she can to promote understanding of the problem and to develop a vaccination programme, as the more vaccination that is carried out, the cheaper will be the cost to dairy farmers.

One of the inhibitory factors so far has been the cost of vaccine. I should also like the Ministry's advice service to draw farmers' attention to the economic benefits of vaccination. The present anticipated cost of £4 per cow per year seems a good investment when compared with possible losses of £10,000, as has been experienced in several farms. I should also like there to be the provision of a continuous reporting system on Leptospira in the farming community, which involves collaboration between the central veterinary unit, the communicable disease surveillance unit and the Leptospira reference unit in Hereford.

This would have the effect of broadening the base of knowledge of what is going on in the farming community and determining from that the direction that further research ought to take in order to get a full understanding of the nature of the disease and what needs to be done.

Action now can prevent much bovine and human misery, and I will draw my remarks tonight to a close by giving the last word to that disease-hit Hereford dairy farmer, who said: We were told that all three of us had only a mild leptospirosis problem, but you can take it from me even the mild attack was agony. Anyone who comes in contact with cows should keep Leptospira in mind if their doctor blandly tells them they have 'flu. That is the nature of the problem. It is the reality of the interface between the two areas, and I believe that the answer lies in terms of animal health, to get at the problem at source.

11.56 pm
The Parliamentary Secretary to the Ministry of Agriculture, Fisheries and Food (Mrs. Peggy Fenner)

I am most grateful to my hon. Friend the Member for Hereford (Mr. Shepherd) for raising this subject tonight. It is, I am sure, a reflection of his great interest in animal health matters generally. No doubt this stems from representing a part of the country with a very strong and significant agricultural and, in particular, livestock industry. The House will have been pleased to have had the opportunity of listening to the points which have been made by him.

I am particularly glad to respond, because it affords me the opportunity to describe some of the important work which has been conducted in this country over recent years in relation to leptospirosis.

It might be of help to the House if I first described certain aspects of the disease in this country and its development in recent years. Over the last 20 years leptospirosis which is caused by leptospira hardjo, has become recognised in Great Britain as a very' common bacterial infection of cattle which may cause outbreaks of mastitis and is a cause of abortion and premature calving.

The problem is not unique to the United Kingdom. It is also found in many other countries, including the United States of America, Australia and Canada. As my hon. Friend pointed out, it has also been widespread in New Zealand, where he noted that at one time over 90 per cent. of herds were infected.

In the context of research into methods of control, I would like to offer a word of praise to the scientists and the veterinarians working in my Department. They have been actively studying this disease over recent years. Without wishing to complicate the issue, it may, for example, Mr. Deputy Speaker, interest you to know that leptospirosis is caused by a bacterial parasite of which more that 160 types have been identified in farm livestock and other mammals, including man.

It is difficult to estimate the economic significance of the disease in cattle. There may indeed be infection in a herd without actual clinical disease. However, if the disease manifests itself clinically through abortion, premature calving or mastitis, quite clearly there is bound to be an effect on farm output and productivity.

This brings me to the human aspects, about which my hon. Friend has spoken. There are economic effects here too because the disease in humans is closely associated with those who work with cattle. More generally, in relation to the disease in humans, it is true to say that during 1983—a fact to which my hon. Friend has drawn attention—the number of people suffering from the effects of leptospirosis increased. A significant proportion of these cases were linked to disease in cattle. In most of these cases the disease was not serious, causing only a mild fever. The increase in the number of reported cases in humans in 1983 is perhaps due in part to the increased incidence of the disease in cattle. On the other hand, I do not wish to give my hon. Friend the impression that this is not a cause for concern, because it certainly is. As my hon. Friend pointed out, it would alleviate the situation a great deal if the trend of disease incidence in cattle were reversed.

Perhaps more significant has been the increased awareness among the farming community, especially those working with dairy cattle. In this context, an effective article on the subject appeared in the fanning journal, Dairy Farmer, in June last year with much reference to the work of Dr. Sheena Waitkins, to whom my hon. Friend paid tribute.

The heart of the matter is how it might be practicable to control the disease in cattle. Not only would that be important for the dairy and beef industries but it would help to deal with the human health problems.

The research carried out under Ministry supervision has centred on three possible ways of controlling the disease—first, a build-up of immunity; secondly, the use of dihydrostreptomycin, known as DSM; and thirdly, vaccination.

There is evidence that a natural immunity builds up following exposure to the disease, but it is not known whether the immunity is lifelong. Furthermore, cattle may excrete the infection in their urine and thus provide a source of infection for other cattle and, indeed, farm workers. Even if the transmission and subsequent immunity were guaranteed, manipulating herd management to facilitate infection of young stock may not always be convenient and herds free from infection would always remain at risk.

DSM is the most effective drug for the elimination of the infection from the kidneys, but, although experiments in the laboratory appear effective, failures have been recorded under field conditions.

The use of hardjo vaccine, to which my hon. Friend alluded, is without doubt an effective way of protecting cattle against leptospirosis. In reaching that conclusion, important trials supervised by the Ministry were conducted in Scotland between 1977 and 1981. The dead vaccine afforded a high degree of protection against the disease and all the evidence is that this is the only practical method of control. In New Zealand, where vaccine has been available on a voluntary basis for some time, there has been considerable success in reducing problems associated with leptospirosis. In this country, vaccine has been available commercially since June last year.

I am sure that my hon. Friend will be relieved to know that the demand for vaccine has been very great, although there is as yet no statistical evidence to show what proportion of the national herd is vaccinated.

Mr. Colin Shepherd

Is my hon. Friend taking any steps to try to develop an awareness of the percentage of the national herd that is being vaccinated? Is there any mechanism for ascertaining that, so that progress with vaccination may be measured?

Mrs. Fenner

My hon. Friend raises an important point, but when I give a rough estimate of the incidence of leptospirosis in this country he may concede that ascertaining the level of vaccination exactly is not yet so valid here as in New Zealand, where more than 90 per cent. of the herd had leptospirosis. As I have said, however, the evidence is that demand for vaccine has been very great. As we regard this method as the only practical form of control, that is very good news indeed.

We have never made vaccination compulsory, and I could not accept that this would be appropriate or even practicable, for a number of reasons. My hon. Friend is probably aware that no other country has adopted this course, including New Zealand, where the incidence of leptospirosis was very high.

My hon. Friend may also be interested to know that no British Government have ever introduced compulsory vaccination to deal with any livestock or poultry disease. It would, of course, be very expensive for the industry, having regard to the fact that a substantial proportion of the herds in the country are free from disease, which is in exact contradiction to what happened in New Zealand. The application of vaccine across the board would give rise to considerable costs, and would represent in our view too much of a broad brush approach. On the other hand, in those herds where the disease has been diagnosed, the owner now has the opportunity to protect his animals through the purchase and application of vaccine.

My hon. Friend referred to the cost. I do not think that the sum he mentioned is costly to ensure such a protection. The market for vaccine is a competitive one, with two major manufacturers producing vaccine, and perhaps more introducing a product on to the market. I suppose that the cost of such vaccine must be measured against the likely economic losses, which I have already described. Such considerations are for the individual owner to bear in mind in reaching what he regards as an appropriate conclusion for his circumstances.

One could suggest that voluntary vaccination is not helpful if one farmer applies it while another does not. From the animal health point of view, this is not so, because that vaccinated herd is protected. The farmer who decides not to vaccinate has to bear in mind two considerations. The first is that his herd is vulnerable. The second is that, if disease occurs in his cattle, his farm workers, and indeed he himself, are also at risk. For all those reasons, I very much hope that farmers will recongise the benefits of vaccination and protect their stock, which will in turn provide protection for those most at risk to the transmission of disease to human beings.

I hope that what I have said will reassure the House that the Government are well aware of the problems to which leptospirosis may give rise. In addition, my remarks will have indicated what we regard as the most appropriate way forward—a way in which the individual herd owner will be able to decide on the most appropriate course in the light of his particular circumstances.

I conclude my remarks by expressing once again my gratitude to my hon. Friend for raising this important subject.

Question put and agreed to.

Adjourned accordingly at seven minutes past Twelve o' clock.