No Increase in Multiple Sclerosis among Veterinarians

To the Edior: Canine distemper virus, a paramyxovirus morphologically related to measles virus, can produce a progressive demyelinating disease in dogs. In 1977, Chan suggested a possible relation with human demyelinating disease.¹ The current dispute over the possible relation between exposure to dogs (particularly small dogs) and the subsequent development of multiple sclerosis was initiated by Cook and Dowling² and further elaborated by Cook et al.³ Other studies have failed to confirm the suspected relation or have been critical of experimental methods.^{4 5 6 7} We sought to determine the prevalence of multiple sclerosis in a group of subjects with increased occupational exposure.