Undulant fever

Undulant fever

19al. PUBLIC HEALTH. 135 Undulant Fever. By D. S. RABAGLIATI,O.B.E., B.SC., F.R.C.V.S., D.V.S.M., Chief Veterinary Officer, YVest Riding" (Yorkshi...

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Undulant Fever. By D. S. RABAGLIATI,O.B.E., B.SC., F.R.C.V.S., D.V.S.M., Chief Veterinary Officer, YVest Riding" (Yorkshire) C o u n t y Council; and Sir ~VEI.DON DALRYMPLE-CHAMPNEYS, BART., M.A., M.D., M.R.C.P., D.P.tt., ;t Medical Officer of the Ministry of Health.

These two papers were submitted at an ordinary meeting held in London on December 19th, 1930, by two of the foremost authorities on the subject of undulant fever in this country. They contain the most recent information with regard to the condition, and aroused a great deal of interest and led to a most useful discussion.

MAJOR RA~BAGLIATI. I l E old adage that " It is an ill wind that blows nobody any g o o d " is well exemplified in the case of undulant fever, for, despite tile serious possibilities that recent discoveries on its incidence and its etiology have brought to light, one most useful feature has evolved and that is that it gives the veterinarian an excellent opportunity of co.llaborating with his medical colleague in its further elucidation and, let us hope, its means of control. The term undulant fever is, I take it, used to describe the syndrome observed in man as the result of an infection with certain organisms of the brucelta type. The genus brucella is a new one, the name being suggested by Meyer and Shaw in 1920, and includes, amongst others, the organisms which were originally known as the micrococcus melitensis, responsible for Malta fever, and the bacillus abortus or bacillus of Bang. The nomenclature is still somewhat confused, but it would appear that the varieties with which we are concerned are now commonly spoken of as brucella metitensis var. metitensis, i.e., the type occurring in the goat, and brucella melitensis vat. abortus, i.e., the type associated with contagio.us abortion in cattle. To these may be added the brucella melitensis vat. suis found in the pig. This last-named, although from a purely veterinary standpoint is not thought to be responsible for very serio.us losses to. pig breeders, has been shown to. be transmissible to. cattle and to be very virulent for man, and may thus well become the most important from a public health aspect in the future. There can be no doubt that what we to-day call undulant fever is nothing else than what used to be known as Malta or Mediterranean fever, although perhaps of a less virulent form. As long ago as 1886, Bruce isolated the organism from human cases of fever which led

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to the discovery of Zammit in 1905 that it was enzootic in the goats of Malta. This again led on to the classic work done by the British Commission on Malta fever, and to the practically wiping out of the disease from amongst our forces stationed in Malta by the order forbidding the use of unboiled goats' milk. W h e n it was seen that the disease still persisted in the civil population, who were not bound by the order, the discovery of the transmission of the disease from g'oat to. man by means of the milk was well proved. In 1887, Bang discovered the bacillus abortus as the causal organism of contagious or epizootic abortion of cattle. This most serious disease has been, and still is, responsible for enormous losses to agriculturists all over the world, and a great deal of work has been carried out by veterinarians with a view to minimising its losses with, on the whole, only a limited success. For many years, owing to. a difference in nomenclature and from the fact that no cases of abortion o1" other condition t h o u g h t to be in a n y way connected with it had occurred in the human race, its relationship to Malta fever in the goat was never even suspected. It was, however, realised that the so-called micrococcus melitensis could also occur both in sheep and cattle as well as in the goat, but its presence in cattle was not recognised as being similar to. an infection with the bacillus of Bang, and in the Near East, where at one time the disease was thought only to occur, the cow was ruled out as a practical propo.sition in relation to. the disease in man. I t was left to Alice Evans to point out the similarity of the two causal organisms in 1918, and I think it was she who wrote: " It was as if two brothers had been adopted by different families and given different surnames and for twenty years no one recognised the similarity in the boys because they were seen at different times and in different places." She

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pointed out that the two organisms were morphologically, culturally a n d bio-chemi(ally indistinguishable, and serologically very closely related. Although, as has been seen, it is now m a n y ).ears since undulant fever or, as it was then called, Malta fever, was known to occur in man, it is only since about 1923-24 that the human disease has been associated with epizootic abortion in-cattle. P r o b a b l y the first authentic cases to be described were those noted by Orpen and Bevan in "Rhodesia and Keefer in the United States o.f America in 1924, although as tong ago. as 1914 K e n n e d y drew attention to agglutinins to brucetla melitensis in the milk and blood of cows in London, and this was confirmed by others. It was not till 1927, however, that the possibility of cows' milk transmitting undulant fever to man was taken seriously, since when cases have been reported r u n n i n g almost into thousands from such countries as America, Sweden, Italy, France, Germany, Austria, Denmark, ttolland, and, what concerns us most, from Great Britain. It is not necessary for me to go into details about the numerous cases described ; sufficient is it to say that I think it must be conceded by all that from the facts laid before us there can be no reasonable doubt that undulant fever can be produced under certain circumstances by the consumption of cows' milk and also by the association with or handling of cattle and pigs, and that this danger is present in this country as welt as abroad. It behoves us as veterinarians to accept this fact until at least we can disprove it, so that we must take stock of the present position and see what can reasonably be done to lessen, if not altogether eliminate the danger. H a p p i l y the cases so far described in man are rare and mild, so that there appears to be no need for panic in consideration of the matter, nor on the other hand from its apparent rarity should we ignore its d a n g e r . Brucetla infection occurs in the following animals as well as i n m a n ; the goat, cattle, sheep, p i g , horse, mule, cat, dog, rabbit, guinea-pig, rats, mice, and it is even stated by some autho.rities that it occurs in the domestic fowl. For all practical purposes, at least until our knowledge of the disease is greatly augmented, we need only consider it in the goat, cattle, and perhaps the pig. The Disease in the Goat.--As a general rule goats show no signs at all, with the exception

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that abortions are common in an infected herd, although many goats act as carriers and even excrete the organisms in their milk witho.ut ever aborting. Dubois reports occasional induration of the udder and even inflammation of joints with now and then sub-acute o.r chronic bronchitis. Personally, from my observation on goats, including many Maltese goats, in E g y p t , with which I had considerable experience, I would suggest that these complications had nothing whatever to do with these brucella infections, but were due to caseous lymphadenitis which was extremely common in goats in that country. T h e milk of infected goats contains the organisms and is liable to. infect mankind both by its consumption and even also, it is said, through the skin. T h e urine is also infective and is liable to transmit the disease by contact with the skin or o.therwise. Kids born of infected goats appear to enjoy an immunity while sucking, but are liable to contract the disease when weaned. I know of a case where a goat was slaughtered as the result of her blood giving a positive-reaction to the agglutination test and when killed two live foetuses were removed, both of which survived. One of these I had for m a n y years, a n d although I had her blooct tested at frequent intervals the result was always negative and she produced m a n y gallons of milk for m y household with no dire results. The Disease in Cattle.--How common contagious abortion of cattle is in this country no one can tell, but that at least 50 per cent. of our herds contain infected cows is a very conservative estimate. He who would make a guess at the number of cattle actually contaminated would indeed be a rash man, for before a n y such figure can be given vastly more cattle must be tested for the disease than have ever been done up to now. I hardly need to detail the symptoms of the disease as they are so well known, and a few remarks will suffice. T h e r e is no general alteration in the health of the affected cow and the conditio.n is more often unsuspected until the cow aborts. Abortion most commonly takes place between the fourth and seventh months of pregnancy, although it may occur earlier. W h e n abortion is late in the period of p r e g n a n c y there are often premonitory signs of a p p r o a c h i n g parturition i when early, there are frequently none. T h e r e is often a tendency to retain the foetal membranes and a dirty vaginal discharge is liable to occur

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for a month or so after the abortion. T h e calf is usually born dead, but, if not, usually dies, although a few m a y be reared. Infection is b r o u g h t about by contact with the affected placenta or discharges. Calves which live are liable also to carry infection to other premises through the contaminated matter in their intestines. T h e commonest method, however, of introducing infection into a herd is the bringing of an infected cow to clean premises. Infection usually enters the body by the mouth, t h o u g h it has been said that discharges may contaminate the genital passages a n d so cause the disease. T h e bull is not now cons i d e r e d t o be so. serious a cause of spread of the disease as was at one time supposed. Cows rarely abort twice, more rarely three times, even though they are still capable of conveying infection. Some cows harbouring the organism carry their calves to full time and are thus often unsuspected by their owners, with the result that they are the most dangerous. T h e disease is practically nonexistent in sucking calves, even although the milk they are fed on is contaminated, but after weaning they are easily infected. T h e most important point about the disease which concerns us at present is the fact that a percentage of affected cows excrete the organisms in their milk, and it is of course these animals which are the greatest source of d a n g e r to mankind. R o u g h l y speaking, about 30 per cent. of infected, cows excrete the brucella in their milk for shorter or longer periods so that when we consider the extent of the disease at a n y time, very m a n y thousands of our milking cows must be a potential danger. Strangely enough, cases are found where the bacilli are only present in the milk from one or two quarters of the cow's udder, but from a practical standpoint this makes but little difference to. the danger. T h e r e would seem to be no rule as to. the length of time the milk remains infective; sometimes it is only for a short time, while in other cases it remains so for years. It is usually necessary to resort to cultural tests or guinea-pig inoculation to ascertain whether or not milk is infective. Diagnosis of the disease in cattle can be made by an examination of the foetal membranes of an aborting cow or even from the hiatus and the finding of the bacilli, but by far the most important method is serological. T h e agglutination test is the most used and probably gives the best results, but in America the complement fixation test is said to be abo.ut

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equal in its efficacy. T h e latter is, however, much more complicated to carry out. Attempts have been made to produce a substance called " A b o r t i n " which is analogous to tuberculin. T h i s has been used both subcutaneously and intradermalIy, though so far no very satisfactory or reliable results have been obtained with it, so that it has for all intents and purposes been given up. Possibly further experiments may result in the preparation of a reliable product. In this country t h e usual test employed is thus the agglutination test. Blood or milk may be used, but blood is the better and the more reliable. T h e agglutination test, despite its reliability, has certain limitations. T h e question as to what dilution is required to assert that the reaction is positive has given rise to considerable differences of opinion. It is generally conceded that an agglutination in a dilution of 1-80 or more may be considered to denote infection but that 1-40 is suspicious. Below this dilution positive results need not be considered. T h e use of a standardised and reliable antigen is also of the utmost importance. It is estimated that in testing" a herd by this means a n y t h i n g from 1 to 10 per cent. of positive cows m a y be missed, but if frequent and repeated testing is adopted these errors become almost negligible. A cow which once reacts usually continues to do so for years, although the reaction gradually gets less pronounced, but the cow may have ceased to be a source of d a n g e r long before her blood ceases to react. T h e length of time after infection takes place before the blood reacts is not constant, and a cow may be a danger before she can be detected. Cotton states that the reaction usually makes its appearance within three to four weeks after infection, but it may be delayed from three to four months, and in occasional instances m a y not appear until after the termination of pregnancy either by abortion or parturition. Moreover, a cow which has recently aborted may not react to the test until 14 to 21 days have elapsed since her abortion. Despite these and other .difficulties, the agglutination test, when all is said and done, is an extremely useful one and when carefully and frequently carried out is a most reliable method of picking o u t reactors from a herd. Cotton shows that in America, of cows whose blood agglutinated to. a titre of 1-200 or above, 80 per cent. were found to be eliminating the bacilli in their milk, while those whose sera reacted to a titre of 1-100 or less were rarely found

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to be d o i n g so. Given a uniform standard of test, the matter might be investigated further so that if this can be confirmed we might possess a method of knowing which cows are likely to be dangerous for the spread of undulant fever and which are not. H e r d s m a y be divided into the following categories :--(a) Clean or uninfected herds, probably rare. (b) H e r d s which harbour a percentage of reactors, but where the disease is more or less stationary, although at any time it may recrudesce. Such herds are suitable for the elimination of reactors. (c) H e r d s in which the abortions are numerous and the .disease progressive and liable to result in what are known in America as " abortion s t o r m s . " Preventive Measures.--(1) General measures of control may be adopted, such as isolation of any cow which shows signs of abortion or, if no signs are noted, immediately she aborts. Such cows should be isolated for two montbs after abortio.n. T h e r e must, of course, be a t h o r o u g h disinfection of the contaminated stalls, destruction of the foetal membranes, discharges and so on. Calves born alive are better destroyed, but if not, should be isolated for two months, but then should not be allowed to associate with mature heifers. Care must be taken of the bull, such as the avoidance of promiscuous services; disinfection of his sheath should be carried out after serving any cows not known to be clean, and other general measures are all of use in limiting the extent of the disease, but from a public health standpoint are of little or no use in the prevention of infected milk. (2) Prevention of the disease by vaccination is of two kinds (a) the use of dead vaccines; (b) the use of a living vaccine. T h e use of the dead vaccine can be resorted to for p r e g n a n t animals, but a l t h o u g h certain authorities claim success for it, it is a method which has by no means found favour with the veterinary profession as a whole. F r o m a public health point of view it can hardly be taken exception to as there does not seem to be a n y chance of its Causing the milk to become infective. T h e ,use of live vaccines is widely practised but is only to be recommended in herds where infection is widespread. It consists in the inoculation of a live virus, but can only be given to non-pregnant cows or heifers, and no inoculated anirr/al must be put to the bull for

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a period of at least two months following the vaccination. Great difference of opinion exists as to its efficacy, and its use is exhorted by some, but condemned by others. T h e r e seems to be no doubt that it has met with great success in reducing the losses from abortion. T h e chief point to be considered about it from a public health aspect is that in America it has been said to give rise to an elimination of the causal organism in the milk. If this is tlle case I fear it will not find favour in the eyes of the medical profession. U n d o u b t e d l y the most careful experiments are necessary to either prove or disprove this assertion. It must be remembered, however, that the live vaccine is usually only used in already badly affected herds, m a n y cows of which are no doubt excreting bacilli in their milk without the use of any vaccine. On some premises, however, where the live vaccine is used it has been the practice to vaccinate all heifers admitted to the herd. T h e Ministry of Agriculture have recently circularised all veterinary surgeons using their vaccine, and will not issue any more unless a declaration is signed which reads as follows : - " I, , hereby declare that I will administer the anti-abortion vaccine supplied by the Ministry of Agriculture and Fisheries only in seriously affected herds in which the presence of b. abortus infection has been established by definite l a b o r a t o r y t e s t s , and from which it is not practicable to eradicate the disease b y the method of isolation. Signed ........................... , M.R.C.V.S." I am informed t h a t at the laboratory of the Ministry of Agriculture at ~37eybridge, where tile vaccine is prepared, no laboratory assistant or other person has ever contracted undulant fever, and moreover, certain experiments have been carried out on vaccinated cows and on no occasion were bacilli demonstrated in their milk. As these experiments have not as yet been published it is not possible to pass j u d g m e n t on them, but it is a point which certainly should be cleared up once and for all. Eradication of the disease by the use of tile agglutination test and the disposal or segregation of reactors is no doubt the ideal method of dealing with the condition, but on a large scale it does not appear to be a method for practical politics, at least not at present. T h e r e is plenty of proof that the method of frequent agglutination tests and the separation of the reactors from the non-reactors, with

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suitable care of the calves, can achieve considerable success even on one f a r m . If reactors are disposed of, the v e x e d question arises as to what s h o u l d be d o n e with those got rid of. W h o is to bear the cost of eradication measures, a n d what can be d o n e in the case of farms where isolation is not possible, are questions to be so.lved in the near future. Abortion in the P i g . - - I t is definitely k n o w n that a brucella infection does occur in the pig, but the losses from it are small a n d pale into insignificance w h e n c o m p a r e d with those caused b y abortion in the cow. In this c o u n t r y it is not a condition which has so far troubled either the pig breeder o.r the v e t e r i n a r y profession. It is certainly now i~nportant that its extent s h o u l d be ascertained, a n d it m a y well be f o u n d that it is a m u c h c o m m o n e r trouble a n d p e r h a p s causes greater loss t h a n is g e n e r a l l y believed. O n l y further investigation can show this. Undulant Fever in Man.--It is not for me to even a t t e m p t to describe the disease as it occurs in man, for we are looking forward to hear this side of the question from the next speaker, but there are certain observations I would like to make. (1) T h e r e can be n o d o u b t that a brucella infection can occur in m a n other t h a n that associated with the goat, a n d that the cow has been p r e t t y welt p r o v e d to be responsible. \Ve know that the o r g a n i s m s are excreted in milk and that milk a n d milk products, especially the cream and butter, are liable to be d a n g e r o u s . Cheese, p r o b a b l y from the acidity associated with its m a n u f a c t u r e , is said not to be nearly so. liable to infect. (2) E v i d e n c e is also ample to show that undulant fever can be c o n t r a c t e d other than from drinldng" infected milk or c o n s u m i n g foods m a d e f r o m infected milk. Contact with cattle a n d pigs is in itself sufficient to b r i n g a b o u t the disease in man, a n d m a n y cases have been described in A m e r i c a a m o n g s t employ~s in stockyards, butchers, farmers, a n d even in v e t e r i n a r y s u r g e o n s . I recently received the particulars of a case o c c u r r i n g in a m e m b e r of the v e t e r i n a r y profession w h o put it d o w n to infection from the removal of placentas from affected cows. {.q~ ( ~ ' h H H r ~ n

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w h o had never d r u n k a n y t h i n g but " Certified " milk contracted the disease. T h e case was s o m e w h a t complicated b y the fact that they h a d been associated with workers in a

l a b o r a t o r y where brucella cultures were b e i n g dealt with. How" much this m a y h a v e h a d to d o with their infection I c a n n o t say. A l t h o u g h a c c o u n t s differ, it is g e n e r a l l y f o u n d t h a t males are affected more than females in the p r o p o r tion of two to one. A l t o g e t h e r the infection seems to be a v e r y selective one, a n d the a g e limit is of some i m p o r t a n c e too. (4) T h e r e can also be no d o u b t that sufficient cases have occurred in this c o u n t r y to w a r r a n t a s h a r p outlook b e i n g kept o n all cases of indefinite fevers and steps b e i n g taken to try to arrive at a diagno.sis lest the case be one of u n d u l a n t fever. (5) It is u n d o u b t e d l y necessary to discover how m a n y normal p e o p l e ' s blood will react to the a g g l u t i n a t i o n test for brucella, for out of justice to the cow this is called for. L e n t z e in i n v e s t i g a t i n g the disease near Breslau, after s u b m i t t i n g the blood of several p e r s o n s to the a g g l u t i n a t i o n test, both those in contact with cattle a n d those k n o w n to have d r u n k milk c o n t a i n i n g br. abortus, concludes that the d a n g e r of infection from milk is v e r y m u c h less t h a n from contact with a b o r t i n g animals. In the ro.utine e x a m i n a t i o n of milk b y the biological test for tubercle bacilli, it m i g h t be advisable to examine for br. a b o r t u s b y the a g g l u t i n a t i o n test of their blood or culturally, all g u i n e a - p i g s used. T h i s Would at least give some idea as to how m u c h milk is infected. T h e question as to w h y so few cases have been recorded when the possible source of infection a p p e a r s to. be so c o m m o n , has not been satisfacto.rily answered as yet. It is said, no d o u b t with truth, that no one has looked for them, but even a d m i t t i n g this, if all cows' milk c o n t a i n i n g the infection was certain to infect, the cases could not have escaped notice so l o n g . It is k n o w n also that the p o r c i n e t y p e is more virulent for m o n k e y s t h a n is the bovine, and: so p r o b a b l y also for m a n . It is p r o v e d that the p o r c i n e t y p e m a y occur in cattle; therefore is it not a possibility that the infections transmitted to. man from the cow are due to. the porcine strain passed in c o w ' s milk, a n d not to the true b o v i n e ? T h i s is a po.int which must not be lost sight of a n d until we have more definite i n f o r m a t i o n available, it

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measures against the disease. T h e r e can be no d o u b t that the total eradication of c o n t a g i o u s abortion from our herds is the ideal w a y of a p p r o a c h i n g the matter, b u t

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we have already seen that it is not practicable at the present time. W e have not even made a n y serious a t t e m p t to get rid o.f b o v i n e tuberculosis, a more simple p r o b l e m f r a u g h t for m a n with much m o r e serious c o n s e q u e n c e s t h a n abortion, so there does not a p p e a r to be m u c h hope that official steps, which would necessarily cost the nation vast sums, are likely to be e m b a r k e d on in the m e a n t i m e . P r o b a b l y before v e r y long, steps wilt be taken to insist o n all cows in " Certified " a n d G r a d e A ( T . T . ) herds b e i n g free from a b o r t i o n as well as tuberculosis. A m e r i c a n opinion seems to fly to pasteurisatio.n as the great d e s i d e r a t u m . P e r s o n a l l y , I have never been one of those w h o a d v o c a t e d universal pasteurisatio_n--frankly I look u p o n it is an admission of defeat in our c a m p a i g n for safe milk---but I c a n n o t now d e n y that there is m u c h to be said for it if we come to the conclusion, which f o r t u n a t e l y we have not so far, tlmt the a v e r a g e milk is to be considered d a n g e r o u s for the transmission of u n d u l a n t fever to man. It must be r e m e m b e r e d , however, b y those in f a v o u r of universal pasteurisation that there are other and possibly more potent m e a n s of m a n k i n d contracting- the disease from animals, a n d also that universal pasteurisation is not a practical possibility in this c o u n t r y . I am g l a d to see f r o m a published discussion on this disease that Sir "~Veldon D a l r y m p l e - C h a m p n e y s takes this view. W e have a l o n g way to g o before the small a m o u n t of pasteurisation that is carried out to-day is sufficiently controlled and inspected to. be reliable, without e m b a r k i n g on more extensive schemes. I would like to mention the old-established practice both in this and in m a n y other countries of keeping- a goat a m o n g s t a herd of cow's for the express p u r p o s e o.f p r e v e n t i n g a b o r t i o n . It is a v e r y old custom a n d I am not g o i n g to v e n t u r e to. explain its origin. Is it merely a belief, is there a n y possibility of a sort of cross-immunisation t a k i n g place between the Malta fever .of the g o a t a n d the abortion of the cow, or is it due to the p u n g e n t smell of certain male goats f r i g h t e n i n g away the s o m e w h a t susceptible brucella ? Not l o n g a g o I was talking to a f a r m e r w h o said that when he took over the farm, his n e i g h b o u r s told him h e could not b r e e d cattle o w i n g to a b o r t i o n always h a v i n g existed on the .farm. H e got some geese to run a b o u t in the f a r m - y a r d a n d of. late. has h a d no abortion

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- - w h i c h he attributes to the presence of the geese. A phenomeno.n but little k n o w n is that certain persons, as far as I know chiefly v e t e r i n a r y s u r g e o n s , suffer from a condition which I think has been termed a " b r u c e l l o s i s . " T h i s condition is evidenced b y a p r o f u s e skin eruption b e i n g b r o u g h t a b o u t on the arms and h a n d s when it has been necessary to rem o v e the after-birth from a cow. W h e t h e r it is only specific for those cases where the retained after-birth is the result of c o n t a g i o u s abortion or whether it is bro.ught a b o u t in a n y case, I am not p r e p a r e d to say, but it would be interesting to find out if the blood of those liable to this p h e n o m e n o n would in all cases give a positive reaction to the a g g l u t i n a t i o n test for brucella. O n e must realise, however, that tile vast m a j o r i t y of retained placentas are tile result of abortion. Let us look for a m o m e n t at what s t a t u t o r y power we possess in i n v e s t i g a t i n g the source of a reported o u t b r e a k in man. O n several occasions I have been informed by a medical officer o.f health that a patient has been diagnosed as suffering from undulant, fever a n d that he or she gets milk from such a n d such a dairy. It is necessary to find out what farm or farms are involved and then to make enquiries from the f a r m e r s as to a n y cases of abortion that have taken place d u r i n g the last few m o n t h s . It is also a great help to communicate with the v e t e r i n a r y s u r g e o n attendi n g the farm if a n y exists. T h e r e is p o w e r u n d e r Article 9 of the Milk and Dairies O r d e r of 1926 to take samples of milk from a n y cow or cows, but none at all to sample the blood of the cows fo.r a g g l u t i n a t i o n purposes, and, should the owner object, this c a n n o t be d o n e . T h e r e is no provision u n d e r a n y e n a c t m e n t to prohibit the use of milk from a co.w even if the milk in question is p r o v e d t o contain the brucelta. T h e o n l y clause which m i g h t be considered applicable is that c o n t a i n e d in Article l I of the O r d e r referred to, in which milk can be p r o h i b i t e d for the food of m a n for a period of five d a y s from a n y cow which is suffering from " a n y infection of the u d d e r or teats, which is likely to c o n v e y d i s e a s e . " It is to m y m i n d v e r y doubtful if this can be t e r m e d an " infection of the u d d e r , " for it is a general condition in which the o r g a n i s m s are m e r e l y excreted in the milk, without the udder itself b e i n g in an actually diseased condition. U n d e r the same Article the milk can be withlield from h u m a n c o n s u m p t i o n for a

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PUBLIC HEALTH.

like period of five .days in the case of a retained placenta or when there is a n y septic condition of the uterus present. T h e o n l y other ordinance which refers to c o n t a g i o u s abortion in cattle is the :Epizootic Abo.rtion O r d e r of 1922, made u n d e r the Diseases of A n i m a l s Acts. In this Order, the only restrictions applied are those m a k i n g it an offence to expose in a sale or m a r k e t a n y cow o.r heifer which is k n o w n to have calved p r e m a t u r e l y within two m o n t h s of the sale, or to sell privately such an animal witho.ut g i v i n g notice of the fact to the p u r c h a s e r in writing, or to send such an animal to a bull without n o t i f y i n g the owner of the bull in writing of the premature calving" within the prescribed period of two months, or to put such an animal in a public pasture, or to allow it in a n y way to. be placed where it can get in contact with cattle b e l o n g i n g to a n o t h e r owner. C e r t a i n l y some f u r t h e r powers are required to. deal with the disease, both from the public health a n d the a g r i c u l t u r i s t ' s point of view, for the O r d e r just m e n t i o n e d is most difficult to. work a n d for all intents anl p u r p o s e s is a dead letter. As I said previously, ff my efforts to draw attention to this disease succeed in creating further interest, a n d if that interest helps in a n y w a y to b r i n g to light more facts t h a n we possess at present, the discussion will not have been in vain. It is absolutely necessary to elucidate more facts, and to get a much clearer idea as to. the incidence of u n d u l a n t fever, before we can hope to. have our s u g g e s t i o n s listened to. a n d regulations for its control framed. Sn~ W E L D O N DALRYMPLECH.kMI?NEYS. It is not, I take it, m y function, even if it were within m y powers, to give y o u an equally c o m p r e h e n s i v e s u r v e y of the h u m a n , as M a j o r R a b a g l i a t i has given of the animal, ff)rm of brueelliasis (as some of our A m e r i c a n friends have t e r m e d it), especially as I have already p r o d u c e d s o m t h i n g of the kind in m y report to the M i n i s t r y of H e a l t h . * I shall, therefo.re, confine m y s e l f to. a few remarks a b o u t u n d u l a n t fever in man, especially as o c c u r r i n g in this c o t m t r y . -,'t-UNDULANT FI¢VER.' With special reference to Animal Sources of Infection and the possibility of its Prevalence in England and Wales. Reports on Public Health and Medical Subjects, No. 56. H.M'. Stationery Office, 1929. Price ls. 6d. net.

Extensiou.--It is, perhaps, hardly necessary m~w, as it was when I wrote mv report, to insist that u n d u l a n t fever can no l o n g e r be r e g a r d e d as a tropical o.r sub-tropical disease, but that it has invaded one n o r t h e r n c o u n t r y after another, some of them our close neighbours, in which it was u n k n o w n or its nature at a n y rate quite unsuspected, and that even this c o u n t r y is far from being" i m m u n e from its ravages. English and Welsh Cases.--ln A u g u s t , 1929, an exhaustive e x a m i n a t i o n of the literature revealed that o n l y 14 :English cases of endemic origin had been reported a p to that time, but, as I r e m a r k e d in m y report, " one should be v e r y cautious o.f a s s u m i n g that this represents the true incidence of the disease in this c o u n t r y , " a'nd again, " there no longer a p p e a r to. be a n y s o u n d reasons for e x p e c t i n g a c o n t i n u a n c e of the f o r m e r ( t h o u g h p e r h a p s only apparent) i m m u n i t y of t h i s , c o u n t r y . " I think 1 can no.w claim without e x a g g e r a lion that s u b s e q u e n t events have p r o v e d these views to be correct. T h e attention which I and others interested have drawn to this disease, a n d the wider, t h o u g h b y no means universal a d o p t i o n of the measures which I r e c o m m e n d e d for its detection, n a m e l y : - (1) the careful investigation and report to the local or central health a u t h o r i t y of all obscure cases of co.ntinued or intermittent fever with s y m p t o m s and signs s u g g e s t i v e of und u l a n t fever in which no other definite diagnosis could be m a d e ; a n d (2) the routine e x a m i n a t i o n by the a g g l u tination test, w h e n e v e r possible, of samples of blood sent for d i a g n o s i s in cases o f continued fever, or even those s u b m i t t e d for the \ V a s s e r m a n n reaction ; have resulted in the discovery of 20 additional cases in which the a g g l u t i n a t i o n titre was sufficiently h i g h to render a diagnosis of u n d u l a n t fever inevitable. U n f o r t u n a t e l y , o n l y 8 of these cases have been reported in the medical press, but accounts o.f some of the o.thers will, I hope, a p p e a r shortly. T h u s 34 cases of u n d u l a n t fever o r i g i n a t i n g in E n g l a n d and W a l e s have either been published or have been privately notified to me, and other cases are v e r y likely k n o w n to y o u . T h i s n u m b e r is, I admit, v e r y small, c o m p a r e d with the steady stream of 300-500 cases per a n n u m discovered in D e n m a r k since K r i s t e n sen started his systematic investigations, but

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PUBLIC HEALTH.

it must be remembered that no such investigation has been carried out here nor, unfortunately, do we possess such splendid facilities for this purpose as our Danish neighbours. I hope, however, that this discussion may so stimulate interest in the subject, that a more thorough search may be made. I should like to take this opportunity of urging all those who come across cases of undulant fever to publish accounts'of them, even if these cannot be complete, in order that the extent of human brucella infection in this country may be ascertained as soon as possible.

Characters of the Disease in this Country.-I am often asked, by those who consult me about possible cases of the disease, w-hat guise it usually assumes in this country. In view of its notoriously proteafl manifestations wherever found and the small number of cases so far reported, an adequate reply is at present impossible. A few general observations are, however, justified by the evidence available and these may perhaps help some of you to suspect the disease, though a definite diagnosis in the absence of a positive blood culture or agglutination to a titre of about 1 in 80 would be rather rash. Perhaps the best way to, illustrate these points will be to tell you about four cases which I recently saw all in one day in the same town. The ages of the patients ranged from ten to forty-four. Two' of them were medical men, another a clerk and the remaining one a school-boy. Two of them were in the habit of drinking large quantities of milk, and one other had done so at an interval before the onset co.rresponding roughly to. the incubation period of the disease, but the remaining patient (a y o u n g medical man) expressed horror at the mention of this excellent food, not, l fancy, the horror naturally resulting from a profound knowledge .of its bacteriology ! The mode of onset and subsequent course of the disease in these cases is also of interest, and shows the extraordinary variations met with in undulant fever, even where one might expect a single strain of the organism to be at work. One patient had a sudden onset with a sudden rise of temperature to 103 ° F., but this came down to near the normal line in about four days and had stayed there for a fortnight when I saw him. The other three patients all had gradual onsets, but the subsequent course of their disease has so far varied considerably. One has had what I would describe (though none of my blood comes

~BRUAR~,

from the Emerald Isle) as a " typically atypical " temperature, in other words, a completely irregular chart except for two characteristic features seldom ~bsent in this disease-the evening rise and the big daily swing. This patient's tfemperature when I saw him had fallen to about 99 ° F. in the evening, after 4 weeks' pyrexia, but I should not be surprised to hear that it has since risen again. Another patient with an equally gradual onset had had ten weeks of pyrexia with only one afebrile period lasting four days. His temperature chart was of the classical undulant type, to which H u g h e s first drew attention, the peaks being moderately high and one over 104° F. T h e last patient with a gradual onset had had very little fever at all and what there was showed considerable irregularity and a small swing, but practically every .day the evening temperature was higher than the morning one. A question which I am sure some of you want to ask me is: " W h a t are the chief symptoms in this disease "? Well, they are extraordinarily varied, but the commonest symptoms in the English cases--and the four I have just described are not exceptional in this respect--are extreme lassitude (in cases with a gradual onset), headache, constipation (which is not usually as obstinate as in melitensis infections), anorexia, furred tongue, mental depression and heavy sweats, which are often of the classical drenching, sour-smelting variety, accompanying the fall of temperature which usually occurs d u r i n g the night or in the small hours of the morning. These sweats, by the way, are often attributed to the taking of aspirin, but occur quite independently of any drug" treatment. Another question, of great importance for the medical attendant, is : " How long will the illness last " ? Of the 'English cases of which the complete history is known to. me the duration has varied from three to 32 weeks, averaging 10 weeks, but in an extremel)~ interesting case which will, I hope, soon be published, tile disease has apparently lasted from 1886 until the present day, or to put it more accurately, the patient has been ill with precisely the same symptoms, except for comparatively short intervals, during the last 44 years and is still so suffering. The English cases are, however, few, and a better guide is perhaps the series ,of 9~ recovered cases reported by H a r d y from Iowa in which the duration ranged from two weeks to 11 months and averaged 15½ weeks.

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T r e a t m e n t . - - Y o u will, 1 expect, want me to say a w o r d here a b o u t treatment. I have no time to give y o u an a c c o u n t of the n u n m r o u s m e d i c a m e n t s which h a v e ' b e e n e m p l o y e d in the treatment of this disease, but in mv o p i n i o n the i n t r a v e n o u s injection of solutions of disinfectants such as m e r c u r o c h r o m e , trypaflavine, B a y e r 205, the salvarsan c o m p o u n d s , colloidal solutio.ns of h e a v y metals, etc., is not free from d a n g e r , a n d g o o d results have not been obtained with a n y of these substances in a sufficiently h i g h p r o p o r t i o n of cases to m a k e their general r e c o m m e n d a t i o n justifiable. This does not, of course, mean that in skilled h a n d s further research m a y not establish one of these s u b s t a n c e s as a valuable w e a p o n in o u r armoury. W h a t a b o u t v a c c i n e s ? Vv*elI, there is no d o u b t that vaccines p r e p a r e d from melitensis a n d a b o r t u s strains have in certain cases g i v e n excellent results, a n d it is a m e t h o d well worth t r y i n g , especially in cases which have s h o w n a n u m b e r of relapses or in w h i c h the t e m p e r a ture, t h o u g h never h i g h , refuses to stay at normal. S h o u l d the vaccines be live or killed? N o t w i t h s t a n d i n g the inefficacy of killed vaccines in v e t e r i n a r y cases, I feel s t r o n g l y that the use of live vaccines in h u m a n cases would be quite unjustifiable, a n d a p p e a r s to be quite u n n e c e s s a r y . A last word with r e g a r d to d r u g s . T h e r e can be no. objection to the a d m i n i s t r a t i o n of such d r u g s as salol b y the m o u t h (and salol itself has p r o d u c e d h a p p y results in some cases), but the regular use o~ an tipyretics, such as aspirin, is strongly contra indicated, as their o n l y beneficial action is to b r i n g d o w n the temperature d u r i n g their exhibition a n d t h e y a d d c o n s i d e r a b l y to the depression which is such a c o m m o n a n d m a r k e d feature of this disease. T h e r e are m a n y other interesting sides of this subject on w h i c h I s h o u l d have liked to have said s o m e t h i n g ; for instance, the d a n g e r of infection from milk a n d the e x t r a o r d i n a r y d i s p r o p o r t i o n between the large p e r c e n t a g e of untreated milk in this c o u n t r y which is certainly infected a n d the small n u m b e r of h u m a n cases so far discovered ;. the possibility of infection in E n g l i s h sheep a n d g o a t s ; the evidence collected b y Lafen4tre and other workers in France, p o i n t i n g to the i m p o r t a n t part p r o b ably p l a y e d bv the urine a n d infected litter of sheep a n d g o a t s in the s p r e a d of the disease in that c o u n t r y ; the p u z z l i n g differences in virulence a n d cultural r e q u i r e m e n t s of a b o r t u s strains in different countries, etc., etc. I have

143

t h o u g h t it well to confine what I h a d to say, however, to the clinical aspects of ,undulant fever in m a n as likely to be of especial interest, because the recognition of the n u m e r o u s cases which I feel sure are o c c u r r i n g in this c o u n t r y is of such u r g e n t i m p o r t a n c e . DISCUSSION. The President (Professor Harold

Kerr, O.B.E.)

spoke of the universality of the distribution of undulant fever, and suggested that in view of the extreme commonness of the disease, particularly in Denmark and the United States, it was probable that much was to be gained by universal pasteurisation. That course had been ad~,ocated in America, where in certain areas all milk had to be pasteurised, the prevalence of undulant fever being given as one of the reasons. Neither Major Rabagliati nor Sir Weldon DalrympleChampneys had referred to the prospect of ridding infected persons of the organisms; if that could be done it would be a considerable advantage. The whole question of undulant fever was becoming a serious one, and was likely to constitute a pressing problem in the future. Dr. R. P. Garrow (Medical Officer of Health, tfornsey) referred to his experiences with the disease and allied conditions in South Africa, Egypt and the Mediterranean. Twenty-one years ago Malta fever had been prevalent in South Africa in connection with the mohair industry, and after a drought of three or four years' duration, goats had died in hundreds and large numbers of the people had suffered from brucella infection. Rheumatism appeared to be the commonest complication of the disease, and, after that, orchitis. Dr. Garrow mentioned that although he was familiar with brucella infection clinically, in only a single instance had he ever considered an undiagnosed pyrexia to be due to undulant fever, and he doubted if the infection was really common in man in this country. Dr. M. A. G. Buckell (Pathologist and Bacteriologist, County Borough of Bradford) instanced a number of cases that had occurred in Bradford. Marked sweating had been a constant symptom, while in the case of two children, lassitude and mental depression had been outstanding features of the attack. In several of the Bradford cases the duration of the illness appeared to be somewhat longer than that mentioned by the principal speakers. Major = General Sir John Moore, K.C.M.G., F.R,G.V.S..(formerly Director of Veterinary Services,

India), said that he did not recollect having seen, during his Army career of thirty-two years, a case of undulant fever in the horse. In India, Malta fever, as it was termed, was prevalent in goats and in human beings, and the subject was engaging much attention when he left some nine years ago. There was a feeling in medical and other circles that the question of undulant fever ought to be thrashed out, and" it was to be hoped that some good would come out of the present discussion. Sir James Dnndas=Grant, K.B.E. (Hon. Consultant in Aural Diseases, Ministry of Pensions), referred to

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FEBRUARY',

the case of a young man who had formerly been in South Africa and also in Malta and bad lately been consuming raw milk on the Norfolk Broads. A fortnight after his return to London he developed an .attack of Malta or abortus fever, proved by an agglutination test. The complications included complete nerve-deafness of the left ear. He wished to know whether such deafness was recognised as a result of this infection, as it was of mumps in which orchitis occurred as in undulant fever. Major Rabagliati, in the course of his reply, said that the injection of carbolic acid solution into cattle had been tried, but, llke many other drug treatments, had been found to be useless. With regard to the use of vaccines as a preventive in man, a French veterinary surgeon had used a mixed vaccine of different strains of melitensis, and had held that it was a necessary procedure in the case of people who handled animals. Sir W'eldon Datrymple-Champneys, however , did not appear to agree on the efficacy of vaccines. In any case, vaccination was not called for in this country owing to the few cases reported. Major Rabagliati did not consider the flesh of cattle, proved to be suffering from the disease, to be harmful, more particularly as it was cooked before consumption. In the majority of cases there was nothing to see when the cattle were killed. Replying to a previous speaker, he said that an enormous mnount of meat from cattle affected by tuberculosis could also, in his opinion, be considered fit for hurnan consumption. Under the laws of meat inspection, each carcase had to be judged on its merits.

Sir Weldon Dairymple=Champneys, replying, said that he had been struck with. the few complications met with in the English cases. He remembered no case of orchitis; the~e had been rheumatic pains in one or two instances, but no definitely swollen joints. With regard to the danger from certified and other graded milks generally, the first case he had seen in this country had been that of a man who had always taken particular care to obtain Grade A (Tuberculin tested) milk, and there was little doubt that he was infected by milk. Though it had always been stated that the disease was very uncommon in young children, it was perhaI)s not quite so uncommon as was generally believed, for he had himself seen cases in children aged 3½ years, 4½ years and ten years. The question of inter-human infection was a difficult one, but it had been said that such infection had occurred in hospital, where nurses were infected by patients. Sir Percy Bassett-Smith, on tI~e other hand, had stated that no case had ever been reported amongst the medical or nursing staffs of the naval hospitals, where hundreds of cases of Malta fever had been treated. Deafness, or at any rate slight impairment of hearing, had been noted in connection with cases of undulant fever; indeed, apparently all the special senses could be affected by the disease.

The British Fishing Industry and the Public Health . - - A t t h e U n i v e r s a l C o o k e r y a n d

fish a s a n a r t i c l e o f f o o d . D r . D . H . G e f f e n (Enfield), proposing t h e t o a s t o f t h e " ;Eat More Fish " Campaign, said that invariably a p a t i e n t w a s p u t o n a d i e t of s t e a m e d fish, b u t , h e a s k e d , w h y w a i t u n t i l a m a n w a s ill before dieting him ? Mr. F. R. Sainty, replyi n g f o r t h e C a m p a i g n , to w h i c h t h e B r i t i s h Trawlers' Federation, representing the trawler o w n e r s o f t h e c h i e f p o r t s in G r e a t B r i t a i n , devotes over £40,000 a year, said that an outs t a n d i n g p r o b l e m w a s to o p e n u p a d d i t i o n a l c h a n n e l s o f d i s t r i b u t i o n to t h e p u b l i c s o t h a t t h e y c o u l d t a k e f u l l e r a d v a n t a g e o f tim fish b r o u g h t to. t h e c o u n t r y . A cordial vote of t h a n k s to. t h e C h a i r m a n w a s a c c o r d e d o n t h e p r o s p o s i t i o n o f I ) r . ~V. M . W i l l o u g h b y ( C i t y of L o n d o n ) .

Food Exhibition at Olympia, London, on J a n u a r y 15th, s o m e s i x t y m e d i c a l ot~icers o f health from various parts of the country inspected the spacious and attractively arranged fish s e c t i o n o f t h e e x h i b i t i o n o n t h e i n v i t a t i o n of the British Trawlers' Federation, organisers o f a n a t i o n a l fish f r y i n g c o m p e t i t i o n t o enc o u r a g e t h e u s e o.f i m p r o v e d h y g i e n i c m e t h o d s a n d a p p l i a n c e s u s e d in fish f r y i n g . At the luncheon which followed, Sir John D. M a r s d e n , B a r t . , j.P., C h a i r m a n o f t h e F e d e r a tion, proposing the toast of the guests, said t h a t l a s t y e a r in B r i t i s h p o r t s 15,000,000 c w t . o f fish w e r e l a n d e d , o v e r h a l f o f w h i c h r e a c h e d t h e p u b l i c t h r o u g h t h e f r i e d fish . t r a d e . D r . C h a r l e s P o r t e r ( S t . M a r y l e b o n e ) , r e p l y i n g in the unavoidable absence of the President of t h e S o c i e t y ( P r o f e s s o r H a r o l d K e r r ) , referred to t h e i m p o r t a n c e o f fish a s a f o o d , a n d t o t h e v a l u a b l e w o r k b e i n g d o n e b y t h e f r i e d fish industry, particularly among the poorer sectibns of the community. Professor A. Bostock H i l l , w h o also. r e s p o n d e d , s a i d t h a t t h e d i e t a r y o f t h e p e o p l e n e e d e d i m p r o v i n g in m a n y w a y s , a n d nothing" w a s m o r e i m p o r t a n t a t p r e s e n t than to impress upon the people the value of

A cordial vote of thanks, proposed by Dr. Charles Sanders and seconded by Dr. G. H. Pearee, was accorded to Major Rabagliati and Sir Weldon Dalrymple-Champneys for their most interesting and instructive papers.

THE Food :Education Society have arranged three lectures on " Food and Food Habits and their connection with Rheumatism, Cancer and other Chronic Diseases," which will be given by Dr. R. Ackerleyat at the rooms of t h e S o c i e t y , 29, G o r d o n S q u a r e , L o n d o n , V~r.C.1, o n F e b r u a r y l l t h , 1 8 t h a n d 2 5 t h , 1 9 3 i , a t 5.30 p . m . Admission to the lectures is free.