Past pets and Paget's disease.

There is strong morphological evidence that Paget's disease is caused by a chronic focal paramyxovirus infection of osteoclasts, but the source of this virus and the reason for the wide variation in the incidence of the disease are unknown. The infection may be a zoonosis, with a domestic animal as the usual host. Past exposure to pets was studied in 50 patients with Paget's disease and 50 age and sex matched control subjects with diabetes mellitus. Dog ownership was significantly more common in the patients than in the control subjects (odds ratios at different ages varied between 4 and 8). 44 of the Paget's patients and 30 of the control subjects had had dogs before diagnosis of Paget's disease (or the equivalent age in the control subjects). Exposure to domestic cats was identical in both groups (26 each), and there was no significant difference in exposure to budgerigars. This suggests that a canine virus (possibly canine distemper) might be the primary infective agent, although other factors probably contribute to the particularly high incidence in the North West of England.