Abstract

McDevitt, D. G. (1973).British Journal of Industrial Medicine,30, 385-389. Symptomatology of chronic brucellosis. A survey of the occurrence of symptoms commonly attributed to chronic brucellosis was carried out by questionnaire in four different occupational groups in Northern Ireland—veterinary surgeons working in private practice, veterinary surgeons employed by the Ministry of Agriculture, general medical practitioners, and a group of forestry workers. The veterinary surgeons generally had a higher incidence of symptoms than the other two groups. This could not be accounted for by age, heavy physical exertion or professional familiarity with disease but could be related to contact with cattle and hence to possible brucella infection. Of the symptoms investigated, sweating, weakness, malaise, irritability, depression, rheumatism, arthritis, and backache occurred significantly more often in the veterinary surgeons than in the others, with selective differences between the types of veterinary practice: the alimentary system symptoms, headache, and insomnia were more evenly distributed between all groups and their inclusion as part of the chronic brucellosis symptom complex must be seriously questioned. The lack of specificity of the symptoms, their occurrence in normal persons, and the finding of high serological brucella antibody titres in asymptomatic persons who are exposed to brucella infection emphasize the need for caution against overdiagnosis. This need is illustrated by the fact that a higher proportion of Ministry veterinary surgeons unexpectedly complain of symptoms now than five years ago. The incidence of symptoms in this group is now approximately equal to that of the veterinary surgeons in private practice, although the latter continue to have much greater exposure to brucella infection. Alternative explanations for this increase are discussed.