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Pets & Animals: New treatment found for fatal cat infection

Dr. Courtney Andrews is excited to share news that a treatment has been found for a type of coronavirus infection that used to be a death sentence for cats 

By now, most of the world is familiar with a class of viruses called “coronavirus”. Cats seem particularly sensitive to them. 

You may have read about the tigers in the New York Zoo contracting COVID-19 from a zookeeper in 2020.

Coronovirus in cats is usually found in their intestines and shed through their feces. This is called feline enterocoronavirus (FECV). This biotype is highly contagious, and most cats are carriers. 

Many of them will never show symptoms. In a small number of infected cats, the virus can mutate into feline infectious peritonitis virus (FIPV). We don’t know exactly how or where the mutation is, but FIPV acts differently in cats. 

It causes severe and until recently likely terminal disease. However, this form does not appear to be contagious. So cats with FIPV do not need to be isolated from other cats.

FIPV presents in cats between three months and 2 years of age, and is commonly seen in multi-cat households or shelter situations, places where there is a high density of cats or cats are under stress.

It can present in the wet form (fluid building up in the chest or abdomen) or dry (pyogranulomas or inflammatory cells infiltrating organs, disrupting their function). Neither FECV or FIPV transmitted to other species.

Diagnosing FIPV is almost as baffling as how it is caused. There is no specific test to run. Your veterinarian uses the symptoms, patient information and lab results to make a presumptive diagnosis. 

Antibody tests are not specific to the FIPV form, and unreliable. PCR testing (polymerase chain reaction) is a sensitive technique, but also not necessarily specific to the virulent form. The gold standard is biopsy of affected tissues, which requires general anaesthesia, surgery and a three- to five-day wait for results. 

For years, once a cat received an FIPV diagnosis, the only thing we could do was try and support the animal through the infection, which was rarely successful. Until very recently, the last six years or so, FIPV was largely terminal. 

Considering it’s usually cats under the age of three that are affected, it was a devastating disease for cat owners and veterinarians.

That is until trials of various anti-virals were started in 2018. 

Scientists have been testing two main classes of antivirals: Antiprotease Inhibitors and Nucleoside Analogs. The trials have been showing so much promise that complete remission is seen in many cats. 

This is amazing news and the evidence of how well these drugs work is only increasing as time goes by. The downside to these great discoveries is that the drugs are not readily available in North America. These drugs were not FDA- or Health Canada-approved for animals.
Many groups have worked hard over the years to get these treatments to North America, and many cats have been treated by using drugs from black market production. This is problematic for two reasons: it bumps up the cost of an already high-cost drug, and; there is no quality control of the drug itself.

But the good news just keeps coming.

As of February, Canadian veterinarians have a legal way to access two of the drugs. Veterinarians working with Health’s Canada’s Veterinary Drugs Directorate (VDD) have been able to get the approval to import compounded versions from the United Kingdom. 

Only veterinarians can request these drugs for a specific case, so we still won’t have them in-clinic ready to use, but this is a huge step forward in getting cats treatment for this terrible illness. 

FIPV is a gut punch. The cats become so sick. As a veterinarian, I would feel so helpless having nothing to offer owners or the cat. It is an exciting time to finally have the ability to legally and safely offer a treatment option with such a high success rate. 

Dr. Courtney Andrews is a veterinarian at Lockerby Animal Hospital, a graduate of the Royal School of Veterinary Studies and dog mom to Argyll and Einstein. Animals & Pets is made possible by our Community Leaders Program.

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Dr. Courtney Andrews

About the Author: Dr. Courtney Andrews

Dr. Courtney Andrews is a veterinarian at Lockerby Animal Hospital, a graduate of the Royal School of Veterinary Studies and dog mom to Argyll and Einstein.
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