SALMONELLA DUBLIN SKIN LESIONS IN A VETERINARY SURGEON

737

the heavy rains there are frequent landslides involving a whole hillside, but no figures of the death-roll are ever

prepared.

Yet, from this squalor come the magnificently dressed samba dance groups, roughly one from each favella. These vie with each other in producing the most colourful and expert dance routines, and in composing the best words, music, and rhythm for their carnival songs. But everybody joins in dressing-up and doing the samba. There is always a band to be heard playing somewhere on the streets, and they all, semi-professionals and amateurs,

dancing, rain or shine, through most of the carniNothing stops the dancing-it’s too infectious. During the year I was there, the rain was very heavy throughout the grand competitive march-past on Sunday night; they looked rather pathetic in their gorgeous outfits, soaked to the skin, but danced the samba and turned cartwheels and somersaults in the puddles all the more, to impress the judges perhaps, or because they could not carry on

val.

control their samba mania. The following morning, when the rain finally stopped, there were bodies everywhereon abandoned floats, in gutters, and in shop doorwayspeople had literally fallen asleep on their feet and were snoring, peacefully enough, wherever they happened to be at the time. If you have a particularly strong dislike for someone in Rio, the time to dispose of him is on the Sunday or Monday of carnival. All normal services (including the police) are largely disrupted at that time, and your chances are close to one hundred per cent of escaping scot-free, mingling with the crowds. If your victim is afavellado, he is unlikely even to be missed except by his immediate family who will be powerless to have you prosecuted. Another predictable feature is a large peak in the birth-rate of the city the following November-and indeed of the whole country, for the atmosphere of abandoned hedonism is found in every city and hamlet where there are similar exuberant mini-carnivals.

Public Health SALMONELLA DUBLIN SKIN LESIONS IN A VETERINARY SURGEON EIRIAN WILLIAMS Pembroke County War Memorial Hospital, Haverfordwest

papules appeared on the arms veterinary surgeon two days after

Discrete

Summary of

a

infected stillborn calf. Most of the delivering lesions became nodular with apical pinhead pustules, and the infective organism was shown to be Salmonella dublin. The need for asepsis in veterinary practice is emphasised, with particular reference to brucellosis as an occupation disorder. an

CASE-REPORT

A veterinary surgeon practising in South-West Wales was asked to attend for review during an inquiry into the incidence of brucellosis among members of his profession. Eight days earlier he had delivered a putrefying stillborn calf, and had repeatedly inserted both unprotected arms into the genital tract. He had then, as usual, washed thoroughly in a solution of povidine-iodine, a potent bactericidal agent which he had also applied to his hands and arms before and at intervals during the operation. The cow was

slaughtered;

no

laboratory

tests were

performed

and it was thought probable that the causal organism was Brucella abortus. Two days later he complained of irritation of both arms and hands and noticed a number of small pale papules, especially on the forearms, most of

INTRODUCTION

SALMONELLOSIS is an infectious disease of worldwide distribution, and the serotype most commonly isolated in cattle in Britain is S. dublin. In cattle the illness usually presents with septicaemia and enteritis 2; calves are more often affected than older animals, and many of them die.3 Abortion, stillbirth, or neonatal death may be due to salmonellosis, but the infection may not be recognised unless products of conception are retained for laboratory tests. S. dublin shows a marked host specificity for cattle, and, while infection may also occur in a wide range of other domestic animals,4 most bovine outbreaks are due to spread direct or indirect from herd to herd.5 In man outbreaks of salmonella gastroenteritis or food-poisoning are more often due to S. typhimurium than to any other serotype,6 and S. dublin is seldom incriminated.’7 Other forms of human infection due to S. dublin are also uncommon. They include

osteomyelitis,8 subphrenic abscess,9 prepatellar bursitis,10 meningitis," and septicaemia, sometimes as a terminal complication of carcinoma or leukaemia,12 and in these sporadic cases the source of the infection is usually unknown. Skin lesions in man, as a result of direct contact, do not appear to have been

described.

Suppurating nodule, 1 veterinary surgeon.

cm.

in diameter,

on

right forearm of

a

which matured into dusky red, firm, and painful nodules. When he was examined as an outpatient, four lesions were present on the outer aspect of his right upper arm, twelve on the right forearm, one on the left upper arm, three on the left forearm, and one on the left hand. The largest on the right forearm was 1-3 cm. in diameter, and the few lesions which had remained papular were less than 0-3 cm. in diameter. Central pinhead pustules had already formed and discharged in four of the larger lesions; but in two-one on the right forearm (see accompanying figure) and another on the left upper arm-the overlying epithelium was still intact. S. dublin was obtained in pure culture from the pustular lesion on the right forearm, and again two days later from the pustular lesion on the left upper arm. The

738

following additional investigations were carried out: Widal reaction negative 1/20-1/320 (S.paratyphiAO; S.paratyphi BO; S. typhi 0 ; S.paratyphi BH; S. typhi H; S. typhimurium H phase 2; S. dublin 0; S. Dublin H). Blood-culture: no growth. Stool-culture: no salmonella isolated. Hxmoglobin 16-4 g. per 100 ml.; white blood-cells 5700 per c.mm. (normal differential count); erythrocyte-sedimentation rate 1 mm. in the first hour (Westergren). Liverfunction tests normal. Serum IgG 1-25 g. per 100 ml., IgA 0-36 g. per 100 ml., IgM 0-128 g. per 100 ml. B. abortus phenol-saline agglutination test negative 1/20-1/5120, mercapto-ethanol test negative 1/20-1/5120, anti-humanglobulin test positive 1/160, complement-fixation test positive 1/20. Paul-Bunnell test positive (normal hererophile antibody of the Forssman type). Four weeks later the patient was re-examined. The lesions on both arms had healed without scarring and he had remained well. The Widal reaction was again negative. Rectal swabs were now taken from the rest of the suspect herd. No evidence of infection was found, but within two weeks a cow aborted, and S. dublin was isolated from the fetal

carcass.

DISCUSSION

eruption which occurs on the arms of veterinary after obstetric procedures-the so-called cleansing rash-has been attributed to hypersensitivity to placental protein when it appears immediately and persists only for a few hours, or to brucella allergy,13 but the evidence for brucella allergy is not always convincing. Of a series of 67 veterinary surgeons practising in South-West Wales, 46 have had cleansing rashes from time to time.14 4 have The

surgeons

believed that the appearance of the rash indicates the presence of brucellosis in the cow, but none of these have confirmed their suspicions by laboratory tests. In the remainder the rash has appeared regardless of whether the cow had been considered to be diseased, and 7 have thought that detergents or bactericidal agents have been responsible. The commonest cleansing lesions are discrete pink red papules which appear some hours after exposure. They are irritating or painful, and may last for several days. 8 veterinary surgeons in the series have had pustular rashes, but one alone has attended showing recent lesions which could be examined bacteriologically. Haxthausen and Thomsen 15 described vividly red follicular papules, the size of lentils, each surmounted by a small pustule,, and, because no pathogens were isolated from the pus spread on a medium of agar with dextrose and glycerin, the eruption was attributed to allergy. It might have been shown, however, using present-day enrichment and selective media that these lesions were infective, and it is also possible that some of the more common papular lesions which appear on the arms of veterinary surgeons are infective, due to bovine pathogens other than B. abortus. In the present case, for example, smaller lesions remained papular and resolved without or

apparent suppuration. At one time the mothers’ attendants were justly blamed for the high incidence of puerperal fever in lying-in hospitals,16 and it is difficult to escape the conclusion that surgeons who operate with live pathogens on their bare arms may sometimes do

harm. There is little evidence, however, that humans are among the important vectors of salmonellosis,3 and on only one occasion has it been shown that veterinary surgeons may indirectly cause the spread of brucellosis.17

Veterinary surgeons maintain that the skin can be effectively sterilised by washing thoroughly after operating; but it seems a reasonable assumption that in the present case the source of the infection was the ill-fated parturient cow, and it would follow that thorough washing is not entirely reliable. An inquiry in South-West Wales 18 showed that 57 out of 63 veterinary surgeons carried out obstetric procedures without wearing gloves and, while the number has since fallen, many are still reluctant to adopt a more aseptic technique. In removing the retained placenta, difficulty may be found in separating the cotyledons through plastic disposable gloves; these gloves usually tear if worn during calving; and few veterinary surgeons seem prepared to wear thick rubber gloves, again because they impair careful

manipulation. In considering the danger

to the veterinary surgeon himself by wearing gloves, the protect far of brucellosis importance outweighs that of salmonellosis. The bovine placenta is the perfect culture-medium for B. abortus,19 and the abraded skin is an effective portal of entry.20 Until brucellosis is eradicated, therefore, veterinary schools should emphasise more the teaching of asepsis, principals should encourage their younger colleagues in the practice of asepsis, and industry should be asked to produce a supple and more durable veterinary

who does

not

glove. The suggestion that farmers should own and retain the non-disposable items of protective clothing worn by veterinary surgeons, including rubber gloves, gowns, and over-shoes, is considered unrealistic; but this would at least help to ensure that veterinary surgeons among human migrants are above suspicion of spreading disease. Meanwhile the measures being directed towards the eradication of brucellosis are hesitant and perfunctory; and their severest critic is the veterinary surgeon in the field, who is especially well informed and especially at risk. I am indebted to Dr. David Morgan, director of the Public Health Laboratory, Carmarthen, for the bacteriological

findings. ADDENDUM

A veterinary surgeon in practice in the North of England has been examined since this report was submitted (J. H. McCoy, personal communication). Lesions had appeared on his arms several days after

he had cleansed a cow assumed to have aborted as a result of brucellosis. Six lesions were found on one arm and four on the other. Each consisted of a small central pustule over an area of inflammation more than 1 cm. in diameter confined to the dermis, and the smaller pustules could only be seen through a magnifying lens. S. typhimurium was isolated from one of the lesions. Blood taken from the cow did not contain antibodies to B. abortus, but antibodies to

739

S.

typhimurium

veterinary

were

present in high titre.

surgeon had not

worn

The

protective gloves.

REFERENCES

Field, H. I. Vet. J. 1948, 104, 251, 294, 323. 2. John, F. V. Vet. Rec. 1946, 58, 211. 3. Gibson, E. A. J. Dairy Res. 1965, 32, 97. 4. Taylor, J. in Food Poisoning. London, 1962. 5. Report of a Joint Working Party. J. Hyg., Camb. 1965, 63, 223. 6. Cockburn, W. C. in Food Poisoning. London, 1962. 7. McCall, A. M. Lancet, 1953, i, 1302. 8. Miller, A. A. Br. med. J. 1954, i, 194. 9. Davies, D. G. Mon. Bull. Min. Hlth, 1954, 13, 202. 10. Purnell, G. V. ibid. 1952, 11, 96. 11. Smith, J. J. Hyg., Camb. 1933, 33, 224. 12. Communicable Disease Report, Public Health Laboratory Service, July 11, 1969. 13. Huddleson, I. F. Brucellosis in Man and Animals. New York, 1.

1943.

14. 15.

E. Unpublished. Haxthausen, H., Thomsen, A. Arch. Derm. Syph. 1931, 163,

16. 17. 18. 19. 20.

Semmelweiss, I. P. Z.k.k. Ges. Aerzte Wien, 1847, 4, 242. Sjollema, P. Personal communication. Williams, E. British Veterinary Congress, 1968 (unpublished). Smith, T. J. exp. Med. 1919, 29, 451. Hardy, A. V., Hudson, M. G., Jordan, C. F. J. infect. Dis. 1929,

Williams, 477.

45, 271.

Conferences

necessarily include schemes for improvement in the inborn or genetic capabilities of man, but the fallacy of this was made plain, and was illustrated by reference to stockbreeding : specially bred " super-animals " could not at the same time represent the optimum eugenic end-product and also be parents of succeeding generations of super"

animals ". Medawar thus saw no prospect for the contrived genetic improvement of man; so " in the main, for many centuries to come, we shall have to put up with human beings as they are at present constituted ". Miss JUDITH WRIGHT, as a writer, saw the divergence of science and humanism begin from the time of Goethe, the last " poet-scientist ", leading steadily to the antihumanism of present-day technology. Dr. H. C. CooMBS, economist and Chancellor of the Australian National University, examined Science and the Future of Man from the standpoints of social science and animal behaviour. He drew on his own deep interest in aboriginal affairs, and on the writings of Konrad Lorenz and Arthur Koestler, to examine the survival value of genetically based patterns of behaviour. Dr. Coombs discussed man’s " curiosity or the urge to explore" as the essence of science and a faculty which, in the past, had unquestioned survival value, but made the chilling remark that " curiosity, the overwhelming desire to experiment, was, even in the minds of the scientists, a major reason why the Hiroshima bomb was dropped and the reason why, compared with the compulsion of that urge, the demands of humanitarian compassion were scarcely heard. Can it not be, therefore, that even this-the most exciting if not the noblest capacity in man-has itself become a genetic

hazard ?

MAN AND HIS SCIENCE THE 70th birthday of Sir Macfarlane Burnet was marked by a symposium, sponsored by the Felton Bequests, in Melbourne on Sept. 15. Many of the several hundred who attended felt that there were sombre overtones, although Burnet himself considered that the papers were questioning rather than pessimistic. Dr. IAN WOODS illustrated the many areas in which Burnet’s work had influenced the practice of medicine: staphylococcal infection, culture of influenza virus, influenza vaccines, the different strains of poliomyelitis virus, Rickettsia hurneri as the cause of Q fever, the virus of Murray Valley encephalitis, immune tolerance, autoimmunity as a cause of disease, and the function of the thymus. Prof. Gus NOSSAL reviewed Burnet’s great scientific accomplishments and examined the basis of his intuitive genius. Nossal also drew attention to a quality of Burnet that is seldom appreciated: his capacity as a research director and his status as one of the foremost scientific administrators of the 20th century. He achieved this, first and foremost, by retaining his credibility and reputation as a scientist-also by wise delegation, limiting the work of the Institute to a single theme, and giving senior colleagues complete freedom in their research, yet encouraging each to participate for part of their time in a broad team effort. So a sense of collegiality grew up and " The Institute " came to have an importance quite apart from that of the individuals composing it. Sir PETER MEDAWAR’s paper, on the Genetic Improvement of Man, was read in his absence by Dr. Ian Mackay. Medawar first examined the various visions or conceptions of what man’s place in the world might be: he described these as Olympian in which man gains peace of mind through spiritual insight, Arcadian in which man turns back to the tranquil fraternalism of the Golden Age, and Utopian in which man shapes and re-creates the world according to his own desires. The Utopian vision would

"

Prof. FRANK FENNER gave a detailed and rather alarming account, drawn particularly from American writings, of the likely effects of human overpopulation, environmental despoliation, and over-utilisation of natural resources on ecosystems that had taken thousands of years to evolve. He accepted assertions by American visitors that Australia was very like America, although this was not " a matter for thoughtless self-congratulation". Australians were urged to look on the American situation as a warning of what lay ahead unless preventive action was quickly taken. Without this, man on earth had to face a future of increasing misery, even in an uncluttered " lucky country such as Australia. Sir MACFARLANE BURNET gave the final paper, Life’s

Complexities-Misgivings about Models, the models being primarily those of molecular biology. " The model we have built from the biochemical genetics of microorganisms is only a gadget, a mnemonic, to help us in speculation about human biology-it is useless for any practical purpose." He looked to other model systemsthe models of the animal ethologists-to help us interpret the nature of aggression, of the human fascination for weapons, of rank and hierarchies, of territorial imperatives, and of ritualised behaviour. Such models must be developed until they were simple enough to be understood by children-" yet their effective application will call for all the political virtues-wisdom and decision, tact and charm-at their highest level of expression ". Burnet saw this as a time for decisions which would determine whether mankind headed towards Sir Charles Darwin’s " next million years " of overpopulation, war, and misery, or alternatively developed " a stable human ecosystem that must necessarily involve the whole Earth ". The theme of the symposium was epitomised by the final comment by Dr. Coombs: " Never in the history of man was the imperative, ’know thyself ’ so

categorical."