Diseases transmitted by Man to Dogs
There are certain diseases which are primarily of human origin but are acquired by animal like dogs. Among such diseases of major public health significance are tuberculosis of the human type and several animal parasites, including amoebic dysentery.
Mumps:
The chief reservoir of the virus of mumps is man himself. Animals may be a factor in the spread of the disease from time to time. Dogs also may acquire the disease, though only a few cases of mumps in dogs have been reported. The author however knows the case when a young dog was allowed the freedom of going not only into the sick room but even on to the bed of the patient when the latter was suffering from mumps. The dog was reported to be ill with swollen parotid glands; he experienced difficulty in swallowing and the mumps virus showed up in his saliva. After a few days the dog died. Another case of a similar type recovered after two weeks.
Measles:
Measles is another highly communicable disease caused by a virus. Man is the chief reservoir of infection and the disease spreads by droplet transmission of nasal and throat secretions of infected persons. The role of animals in the spread of this disease is not considered of importance. However the viruses of distemper (fatal disease afflicting dogs) and measles have been shown to share identical antigenic components. When scientists infected some dogs with the virus, fever and coryza along with rash were noticed in quite a large number of them. The virus was isolated from them. The relationship between the virus of canine distemper and measles has been used in the development of heterotypic vaccination procedures. Dogs immunized with measles vaccine are subsequently protected against clinical distemper. Even today measles vaccine is available for use in pups of less than 12 weeks of age, but its use is not advisable in pups over 12 weeks of age. Diphtheria and streptococci may also infect dogs.