>
Biogal's e-News No. 2
 
Unexplained Deaths in a Multi-Cat Household
By Ephraim Keren, VMD

I recently gave a lecture that included the subject of Feline Infectious Peritonitis (FIP), the well-known fatal disease of cats. Following my presentation, one of the veterinarians in the audience, Dr. Noam Ronen, came forward to discuss a clinical problem that he had encountered, which involved the occurrence of respiratory illnesses and fatalities in a multi-cat household. These cats were, by in large, adopted as strays and there was a continuing turnover in the population. He noted that another veterinarian had previously diagnosed FIP in similar cases in this population in the past. Dr. Ronen would now like to rule out FIP as a potential etiology on his differential diagnosis list of viral and bacterial etiologies. He asked me for recommendations regarding diagnosis and prevention of this disease.

1. Background - A number of risk factors are known to predispose cats to developing FIP. These include genetic susceptibility and chronic shedding of Feline Corona Virus (FCoV) by cats in multiple-cat households or catteries. It is important for practicing veterinarians to understand that FCoV, by in large, infects the GI tract without causing clinical disease. While only a small percentage of cats that become infected by FCoV ultimately develop FIP, the problem can be of great concern. Veterinary medical treatment of FIP may sometimes achieve remission of clinical symptoms, however, the disease is virtually incurable and associated with a progressively debilitating fatal outcome. 

2. Clinical Signs - Typical initial signs of FIP in young cats include lethargy and fever, which does not respond to antibiotic treatment. The disease progresses to either "wet" or "dry" forms. Cats with "wet" FIP develop pleural or abdominal effusions, which may cause difficult breathing or abdominal distension. The "dry"form is associated with masses (granulomas) usually affecting the kidneys, abdominal lymph nodes, eyes, and/or brain. (1)

3. Diagnosis - The diagnosis of FIP is based on both clinical and laboratory findings. A number of tests are useful in working up suspected cases of FIP. These include a Complete Blood Count (CBC) and antibody titer to FCoV. CBC abnormalities include an elevated white blood cell and total protein count. Whereas a positive antibody to FCoV titer does not confirm a diagnosis of FIP by itself, most cases of FIP have very high FCoV antibody titers. A negative antibody titer often, but does not always rule out a diagnosis of FIP. Characteristic cytology of effusion fluids or biopsy histology of masses contributes to the diagnosis, however confirmation of FIP is based on identifying FIP virus in tissues via immunochemistry techniques.

4. Prevention Guidelines    
I. Practice Good Husbandry(2)  in order to minimize or prevent exposure to FCoV.
►  Keep clean cat litters and well-separated from food and water.
►  Reduce overall cat numbers and keep cats in small socially stable groups of 4-6 cats. 
►  Isolate queens about 2 weeks before delivery to give them time to get over stress-induced corona virus shedding.

II. FCoV Serology(3) - Knowing that a cat is FCoV antibody positive indicates that the cat is at risk for developing FIP.  
(a). Test cat(s) who have been in contact with a cat suspected of excreting FCoV. Testing can be useful to obtain an antibody titer, which can be used for comparison, when in 2-3 months a repeat test is taken to determine whether the antibody titer is declining. If so, the cat isn’t shedding FCoV and will not develop FIP.   
(b). Test before mating with a known positive or negative cat. It is important that cat breeders avoid infecting their own or another person’s cats by only mating antibody positive cats to antibody positive cats, and antibody negative cats to antibody negative cats.  
(c). Screen cats in a household for the presence of FCoV. It is not always necessary to test all the cats in a household to establish whether or not FCoV is present. If the cats are in groups, then only a sample from each group need be tested. Usually, when FCoV is endemic, over 90% of the cats have antibodies. In control programs, the cats are tested every 2-3 months and as cats’ antibody titers decline to zero, they are put in with the negative group to prevent re-infection.  
(d). Screen a cat for introduction into a FCoV-free household. Once a household is FCoV-free, it is vital to stay that way, so all new cats and kittens need to be tested antibody negative before being      

III. Selective Breeding - It has been estimated that about 50% of the cases of FIP involve inherited susceptibility. Dr. Susan Little has recommends that breeders keep track of FIP cases, look for common parentage, and consider removing sires from their breeding program that have produced kittens that died of FIP.

References:
(1) Dr. Niels Pederson www.vetmed.ucdavis.edu   
(2) Dr. Susan Little, 2nd International FCoV/FIP conference 
(3) Dr. Diane Addie, www.catvirus.com


A Technical Tip
Warming up Biogal’s ImmunoComb® Antibody Test Kits is essential. The kit is based on enzymatic reaction, therefore it requires warm room temperature of 20° – 25° C (68° – 77° F). Since the kit is stored in the refrigerator, it is highly recommended that when you plan to perform this assay, you take out the kit from the refrigerator and you maintain all elements in warm room temperature of 20° – 25° C  (68° – 77° F), preferably for at least an hour. This way you will receive optimal results! When you are finished performing the test, it is necessary to reorganize all elements back into the box and store it in temperature of 2° – 8° C (36° - 46° F) in the refrigerator. Mind you, that Biogal carried out several experiments ensuring the quality of tests done following 12 of these cycles of temperature changes. Findings showed that the 12th test was as accurate as the 1st.

For any further assistance contact us at: info@biogal.co.il