Dear Dr. Fox: I just lost my sweet, affectionate Bosco to feline infectious peritonitis (FIP). He was only 4-1/2 years old. I've talked to his regular vet and have done research on my own, but I would appreciate your thoughts as well.

It appears that while there are tests to detect feline corona virus, there is no test to accurately determine the presence of the specific corona virus that causes FIP. There is a vaccine, but it's not very effective and sometimes even causes FIP. The FIP virus is transmitted via saliva and feces, so keeping litter boxes and food bowls clean and disinfected is crucial.

Is there anything else I can do to make sure that my other cat, Spike, doesn't develop FIP? If I adopt another cat or kitten (which I will likely do because I agree with you that domestic animals are happier living with another of their own kind), how can I ensure that the new cat doesn't develop the illness? Or is my only option to watch and wait? -- N.P., Washington, D.C.

Dear N.P.: Spike could be a carrier of this virus and infect a new cat. This corona virus is highly contagious and in most cats that become infected only causes transient diarrhea and then the cat recovers.

Why it mutates in the intestines and invades the body to cause generally incurable (wet or dry, effusive or non-effusive) immune-system responses is not known.

Feline genetics and epigenetic factors (including nutrition and social/environmental stress) influence how the body reacts to infectious agents like viruses and bacteria. Generally, symptoms are treated with anti-inflammatory, immune-system-suppressing and modulating drugs. The available vaccine is not recommended.

Good nutrition (no "junk" pet food) and a harmonious, safe environment is the best prevention. So I advise you to follow that path, and watch and wait for two to three months before adopting a healthy and compatible feline companion for Spike.

Dear Dr. Fox: I've discovered "naturopathic" food products for dogs late in life and am sorry it has taken so long for them to become somewhat mainstream. Your recommendation for using herbal products was a big plus here.

I use serrapeptase and have given some to my daughter for her older, overweight dog. I use natural products (flea repellent, etc.) for my older Yorkie mix. I've started her on coconut oil, and her coat is returning to a lovely auburn color.

She walks with me twice daily and looks great. She did have a cough (with gagging) that you described, but I switched to a harness for our walks, and that truly was a miracle treatment. I cannot tell you how much that means to me.

I've visited your Web site and copied the recipe for home-cooked meals. She originally balked at the vegetables, so I chopped them in the food processor and she does fine with that now. She also gets a high-quality dry food for crunchies. -- D.T., Springfield, Mo.

Dear D.T.: I am glad that you have taken more responsibility for your dog's health. It amazes me how little people know about basic preventive health care, maintenance and alternative treatments to the costly prescriptions too many drug-pushing doctors advocate.

Serrapeptase is purportedly an effective anti-inflammatory product that I would use in conjunction with turmeric. And yes, coconut oil -- about one teaspoon in the food for a 15-pound dog -- is good for the coat.

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