By John Andersen, DVM

Humane euthanasia (putting an animal to sleep) is something I have to do a lot of. I see the full gamut of human emotions when people lose their pets, from complete breakdowns and intense sadness to casual disregard for what has just occurred. Most people’s response is appropriate and part of my job is to help them through this very difficult event. They need to know if the time is right or not, if the animal is suffering or not, and what to expect. It is a journey into unknown emotions and is always a stark reminder that life is very precious.
Many clients ask me how I do it, assuming that it must be hard to put animals to sleep as part of my job. Although it is never a pleasant experience, the majority of times it is not an unpleasant one either. Most of the pets we put to sleep are old and suffering with a terminal illness. These pets have lived a full, spoiled life and it is simply their time. Whether it’s cancer or organ failure, these animals typically have constant pain, nausea, or disability, and no hope is in sight. Instead of letting nature take its course, which often takes a very long time, we can stop their suffering. Each owner has a different take on this process and I have learned to respect everyone’s own beliefs on such a personal decision.
Most euthanasias eventually lead into a discussion of the pet’s life story, how much it meant to the owner and their family, and tales of mischief and adventure. Euthanasia can close the long, natural process of death and I am glad I am able to help people through this event with compassion and care.
Although most euthanasias are the end of a long, good life, euthanizing sick kittens has got to be one of the worst parts of my jobs. Because of a viral disease called FIP, it is something that I must do all too often.
FIP stands for Feline Infectious Peritonitis, an ultimately fatal virus that infects young cats. As common as FIP is, it is still somewhat poorly understood.
FIP is actually a mutated form of a widespread intestinal virus called Feline Coronavirus (FCV). FCV is widespread in shelters and stray cats, but usually just causes mild, self-limiting diarrhea. The majority of cats who acquire FCV simply get over it and never look back. Unfortunately, in some kittens and young cats, FCV will undergo a genetic mutation and transform into FIP. That sounds like horror science fiction, and I guess it kind of is. This transformation is poorly understood, but once changed into FIP, the virus eventually will cause the kitten to become sick and die.
FIP usually progresses over several months. A typical case usually involves the adoption of a seemingly healthy kitten from a shelter or friend. The kitten is playful and active and the future is bright. Several weeks or even months later, we get a call that the kitten seems sick. These kittens usually have fevers and seem depressed—most kittens are very wild and rambunctious. We may not always suspect FIP in these initial appointments because there are a ton of other more common viruses that cause fever and lethargy. So perhaps we prescribe some supportive treatment. But the FIP cat does not get better. The fever remains, and the kitten starts to lose weight. Clinically, this is one of the dead giveaways for me—a sick kitten with a fever who has lost weight. They are in a time of their lives when they should be gaining weight. Only something very serious causes a kitten to lose weight.
FIP makes cats sick through a very complex interaction with the host’s immune system. The FIP virus causes inflammation throughout the body that leads to a fever, leaky blood vessels (vasculitis) and a sick cat. The vasculitis can lead to swelling in the brain and fluid buildup in the lungs or abdomen.
Unfortunately, there is no definitive test for FIP. It’s difficult to acknowledge this to owners when we are telling them their kitten “most likely” has a fatal virus. However no blood test or sample can positively identify the virus. We can only rule out other diseases and build a body of evidence for FIP. Elevated immune proteins and changes in the kitten’s white blood cell counts are very suggestive. Fluid in the abdomen is also highly suggestive.
You can test for the Feline Coronavirus, although this test is essentially meaningless because a large percentage of cats have had coronavirus without any serious consequence. There are also false negatives.
In most cases, though, it is pretty clear that the kitten has FIP. These are often five- and six-month-old kittens who are the joy of a little girl, or the pride of a young couple. These kittens look like they’re 18 years old: they’re skinny, not eating, and very lethargic.
Sadly there is no treatment for FIP; these kittens all die. We can give medicines to help them feel better and give them a little more time, but the virus always wins.
Eventually it’s time to put the kitten out of its terminal suffering. These euthanasias are the tear-jerkers for me. This is life telling us it is not fair or easy. At least these kittens had youth and a home where they were probably spoiled and cherished. Their time on earth may have been short, but maybe they were sent to remind us that life is very precious indeed and a gift that must not be squandered.