He remembers one man with non-Hodgkin's lymphoma whose doctor encouraged him to give up his two birds. He gave them up, then died six months later. Another man who had had his cat for 18 years at the time of the cat's death was thinking of looking for a boyfriend to keep him occupied, until a friend asked how many of his boyfriends lasted for 18 years. He went out and got two cats. In my mind the epidemic really is an equal component between physical health and mental health.
Mental health pushes the physical health.
And I believe research will find some magical, mystical substance in dog saliva that we benefit from when they lick our face. Remember that some cats can be very affectionate. Also, puppies may be too much work for someone with advanced disease. Plus, with older animals, you can see whether their size and temperament agree with you. Most birds pose a minimal risk for transmitting disease.