A national survey of human Mycobacterium bovis infection in France. Network of Microbiology Laboratories in France.

OBJECTIVE

To evaluate the role of Mycobacterium bovis in the epidemiology of human tuberculosis in France.

DESIGN

A national survey in France in 1995 using a questionnaire mailed to all French microbiological laboratories performing mycobacteria cultures.

RESULTS

M. bovis was isolated in 38 out of 7075 cases of bacteriologically confirmed tuberculosis (0.5%) notified to the National Reference Centre (CNR) in 1995, resulting in an incidence of 0.07 per 100,000 population. Incidence rates increased with age, and were the highest among patients of 75 years or more (range 0.02-0.33/100,000). Two cases of tuberculosis due to M. bovis were reported in foreign-born children who had come to France for treatment of their disease. No cases were reported among French-born children. The site of tuberculosis was pulmonary in 17 cases, extra-pulmonary in 14, both pulmonary and extra-pulmonary in one, and unknown in six. Extra-pulmonary sites were more frequent in older patients, and pulmonary sites more frequent in younger patients. Two patients were coinfected with the human immunodeficiency virus. Occupational exposure was identified in 13 cases and ingestion of non pasteurised milk in three. In addition, 11 patients had a possible risk of exposure related to their country of birth, family contact or occupation.

CONCLUSION

In France, the 0.5% proportion of human tuberculosis due to M. bovis is similar to that of other developed countries. The higher incidence of the disease among older people is likely to reflect the efficacy of the control measures for tuberculosis in cattle.