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With all that has happened globally within the past couple of years, Coronavirus is not a word that should be thrown around willy nilly. Some may associate Coronavirus with CoVID-19. Others may think all Coronaviruses are transferable to humans from animals.

Today, be talking about Feline Coronavirus, for anyone who might be worried about their precious kitty’s health (and how it might impact them!)

First, though, here’s a review of exactly what Coronaviruses are…

Let’s Talk About Coronaviruses

Coronaviruses are single-stranded, enveloped, positive-sense RNA viruses that belong to the Coronaveridae family.


The meaning of Coronavirus may have the average human scratching their head in bewilderment, but the definition isn’t the important part. The point is that all coronaviruses are structured this way.

A Coronavirus can be specific to a particular species, like:

A Corinavirus can also be zoonotic, transmitted from one species to another like avian flu or H1N1. Despite the category or the circumstances, all Coronaviruses are single-stranded, enveloped positive-sense RNA viruses.

Coronaviruses infect many mammals, including:

  • Birds
  • Humans
  • Livestock
  • Wildlife
  • Domesticated animals

Coronaviruses can be divided into groups. These groups are;

  1. Alpha
  2. Beta
  3. Gamma
  4. Delta

Too much to grasp? Don’t stress. These are just basic definitions to help understand the broad spectrum of Coronaviruses.


Alpha coronaviruses occur in mammals. Alpha coronaviruses often affect the intestinal tracts causing gastrointestinal discomfort. Feline, Canine, and some human coronaviruses exist in this category.


Beta coronaviruses present themselves in mammals like cats, dogs and humans. Instead of gastrointestinal upset, however, Betacoronavirus causes mild to severe upper respiratory symptoms.

Canine Respiratory Coronavirus is in this category, as well as the human virus causing the common cold.

Gamma & Delta

While alpha and beta coronaviruses are known to originate in bats, gamma and delta coronaviruses originate in birds. Delta Coronaviruses are a relatively new classification of Coronavirus in songbirds and leopard cats in China.

There will be more coronaviruses to come. Unfortunately, evolution applies not just to humans and animals but also to the viruses that attack them. Coronavirus is a vast topic to cover, better explained by scientists, so, back to Feline Coronavirus.

What is Feline Coronavirus?

Feline Covid
Feline Coronavirus is a virus that is specific to cats – both wild and domesticated. Feline Coronavirus causes infection of the mucous membrane of the small intestine. This infection may cause gastrointestinal discomfort or gastroenteritis.

Some cats, however, may be entirely asymptomatic, possibly showing mild symptoms of cat cough or other upper respiratory infections.

These symptoms include:

  • Watery eyes
  • Sneezing
  • Nasal discharge

For the sake of awareness, Feline Coronavirus can be split into two categories. 

  1. Feline Enteric Coronavirus or FCoV
  2. Feline Infectious Periodontitis or FIP

Please keep in mind that these two versions of Feline Coronavirus begin as the same intestinal infection. Yet, a mutation can occur in some cases, causing a dangerous condition in cats called Feline Infectious Peridontitis.

Feline Enteric Coronavirus

Feline Enteric Coronavirus
Feline Enteric Coronavirus may be referred to as FCoV or FECV.

Why so many acronyms?

Well, every Coronavirus requires diligent studying before scientists and doctors can define the virus and the diseases it causes.

For a long time, scientists and veterinarians assumed Feline Enteric Coronavirus and Feline Infectious Peridontitis were two completely different viruses caused by two separate infectious agents. Eventually, they concluded that FIP was actually a variant of FECV caused by often uncontrollable circumstances.

So, Feline Enteric Coronavirus is now referred to as plain old Feline Coronavirus with a possible mutation into FIP or Feline Infectious Periodontitis.

What is Feline Enteric Coronavirus?

Feline Enteric Coronavirus is the less severe of the two strains of FCoV. However, FECV is quite prevalent, infecting about 90% of cats in multi-cat households worldwide.

Many cats may be asymptomatic, showing no clinical signs whatsoever. 

Feline “Enteric” Coronavirus, enteric meaning “affecting the intestines”, causes an infection of the mucous membrane in the small intestine. After a couple of days, after antibodies develop, they work to eliminate the virus through shedding. The virus “sheds” through the faeces in otherwise healthy cats. FCoV may cause diarrhoea in cats.

Usually, Feline “Enteric” Coronavirus doesn’t require medical intervention, only supportive care from a loving cat parent. However, kittens and some immunosuppressed cats are at higher risk of developing symptoms that may be detrimental.

Feline Coronavirus Signs & Symptoms

Feline Coronavirus Symptoms
Signs of Feline Coronavirus can easily go unnoticed by even the most attentive cat, mom or dad. Feline Coronavirus signs and symptoms are relatively mild in most cases, involving the intestines and causing gastrointestinal discomfort.

Top 5 Most Common Signs of Feline Coronavirus

  1. Diarrhoea
  2. Vomiting
  3. Abdominal Pain
  4. Lethargy
  5. Fever

Feline Infectious Peritonitis – The Feline Coronavirus Mutation

Feline Coronavirus Mutation
In a small number of cats with certain strains of Feline Coronavirus, a calamitous mutation occurs, causing the development of Feline Infectious Peritonitis, more often referred to as FIP.

This mutation of Feline Coronavirus is theorized to be caused by one of two things:

  • An abnormal immune response to the virus
  • A predisposed genetic variant or abnormality

What Is Feline Infectious Peritonitis?

Feline Infectious Peritonitis causes the FCoV antibodies, which would otherwise protect the cat from the virus, to mutate into a criminal enemy of the body.

The disloyal antibodies then infect the cat’s white blood cells. As a result, the white blood cells are carried throughout the body, destroying the immune system.

Feline Infectious Peritonitis leads to the deteriorating health of the unlucky cats that are affected.

Signs and Symptoms of FIP include but are not limited to:

  1. Weight loss
  2. Effusion in abdomen and chest
  3. Anaemia
  4. Uveitis
  5. Defecating outside of the litter box

Weight Loss

Weight loss is a common sign of many conditions, mild to severe. Quick weight loss is a definite indication that something unsavoury is going on. Many symptoms can cause an animal to lose weight, like pain, lack of appetite, listlessness, or lethargy.

Effusion In Abdomen and Chest

Feline Infectious Peritonitis often causes a severe inflammatory response. This response can lead to effusion.

Effusion is the escaping of fluid into different body cavities and organs. The infected white blood cells can then end up in the most dangerous places, such as:

  • Brain
  • Kidneys
  • Abdomen
  • Chest


When the body stops producing red blood cells at the normal rate, this is called anaemia. Anaemia is a sign of something serious. For example, feline Infectious Peritonitis can cause anaemia as the immune system collapses.


Uveitis is a painful eye condition prevalent in cats. Uveitis causes inflammation of the uveal tract, the layer of tissue between the outer and inner layer of the eye.

Uveitis can lead to damage and the breakdown of the eyes’ protective barriers, causing severe discomfort, severe sensitivity to light, and even blindness.

Defecating Outside Of The Litter Box

Cats like to keep things clean. They aren’t going to poop in their living spaces unless something is up. Maybe a busy feline foster parent forgot to refill the litter box and ended up with a surprise on your pillow that night? Or a cat may be indicating sickness or disease. Either way, this is a red flag that something is up.

How Long Does it Take for FIP to Develop?

First things first, FIP itself isn’t contagious. FIP develops as a result of a mutant strain of Feline Coronavirus that only occurs in predisposed cats.

It can take several months after the infection of Feline Coronavirus for Feline Infectious Peritonitis to develop. By this time, the virus that causes FCoV has most likely been expelled from the cat’s system.

Remember, FCoV causes the viral infection that mutates into FIP in 5% – 10% of infected cats.

Feline Coronavirus and FIP in Kittens

FIP in Kittens
Though a cat may be infected with Feline Coronavirus at any age, kittens are more susceptible for a few reasons, including:

  1. Purebred
  2. Underdeveloped immune system
  3. Mother to kitten transmission
  4. Stress


Studies say that purebred cats account for 1.3% of FIP cases while only 0.35% of mixed breed cats develop the disease.

Some breeds are thought to be at higher risk than others, like:

  • Absynnians
  • Bengals
  • Birmans
  • Himalayans
  • Ragdolls

There is still much to be learned about Feline Infectious Peritonitis and its prevention and vaccination.

Underdeveloped Immune System

Kittens are always at higher risk for any infectious disease, viral or bacterial infection than their adult counterparts. Due to their underdeveloped immune systems, kittens are vulnerable to a myriad of viral and bacterial infections, including Feline Coronavirus.

Feline Enteric Coronavirus can be more dangerous for kittens. A bout of diarrhoea can have serious consequences for a tiny furball weighing only a few pounds leading to dehydration and sometimes even death.

Mother To Kitten Transmission

Mother-to-kitten transmission of Feline Coronavirus of the most common and sure-fire ways a cat acquires the infection. Kittens who nurse from an infected mother will have feline Coronavirus, but the development of FIP is still rare.


Early life is tough enough for a kitten without extra stressors like Feline Coronavirus. As mentioned above, kittens are already more susceptible to infection and disease because of an underdeveloped immunity. Add the stress of living in a shelter, and its amazing kittens manage to pull through.

Stress in kittens may be caused by:

  • Early weaning
  • Abrupt diet changes
  • Community overpopulation

Is Feline Coronavirus Contagious?

Is Feline Coronavirus Contagious?
Yes, Feline Coronavirus is contagious from cat to cat.

After FCoV is contracted, it takes about one week for viral shedding to begin. However, viral shedding may continue for anywhere from 2-10 weeks! During this time, cat’s are contagious to other cats, particularly if they are sharing a litter pan.

How long does Feline Coronavirus survive in the environment?

Outdoors, Feline Coronavirus, last for a mere few hours. Inside, however, in a contaminated litter pan, the virus can last for up to seven weeks!

How Does Feline Coronavirus Spread?

How Does Feline Coronavirus Spread?
Feline Coronavirus spreads through the faeces; therefore, multi-cat households are more likely to see cases of FCoV. About 90% of cats in multi-cat homes will contract FCoV.

Here’s how it works:

  1. Cat #1 lives unbothered as the only cat with his owner in an apartment.
  2. The owner adopts cat #2 from the animal shelter, breeder, animal rescue or the like.
  3. Cat #2 has FCoV, most likely from the shelter
  4. Cat #2 uses the litter pan in his new home.
  5. Cat #1 uses litter which is now shared with cat #2
  6. Cat #2 contracts FCoV from exposure to cat #2’s doo-doo.

It’s as simple as that, folks. Luckily the FCoV infection tends to be pretty mild, manifesting with minor to moderate symptoms.

Feline Coronavirus spreads quickly in places where cats share things like:

  • Litter pans
  • Food and water bowls
  • Toys
  • Bedding

Since cats who share often are more at risk for FCoV, it only makes sense that FCoV would be more prevalent in cats who frequent places where many cats congregate. These places may include:

  1. Animal shelters and the like
  2. Multi-cat households

Animal Shelters and the like

Cats are the most susceptible to Feline Coronavirus in places where cats are nearby and sharing litter pans or food and water bowls. Places like these may include:

  • Catteries
  • Boarding facilities
  • Foster rescues

A study showed 15% of feral cats have FCoV antibodies at the time of admittance to a shelter. However, after a few weeks of being in the shelter and being housed with one or more other cats at any time, virtually all cats tested positive for FCoV antibodies. 

Multi-Cat Households

Cats are awesome. Having one cat is a slippery slope to having five. They are full of personality and just so cute, but just like in a family home with several members, viral and bacterial infections spread easily.

Prevention of Feline Coronavirus

Prevention of Feline Coronavirus
Preventing Feline Coronavirus infection in multi-cat homes can be challenging but not impossible. Here are some helpful tips to avoid illness in the house.

How To Prevent the Spread of Feline Coronavirus

Two cats, one litter panHave several litter pans

Keep litter pans as clean as possible

Scoop waste from litter pan often

Adopting a new catIsolate the new cat in one room with their own litter pan, bedding and food and water for the first few weeks
Contaminated Food and Water BowlsHave cats eat out of separate bowls

Clean and change food and water bowls daily

Keep bowls away from litter pans.

Handling multiple cats.Wash hands between handling each cat

Can Feline Coronavirus Transfer to Humans?

Is it Contagious to Humans?
Oh, humans, not everything is about us, but no. Humans cannot contract Feline Coronavirus. However, the virus could plausibly be transferred between cats from human handling. So, wash your hands frequently.

Feline Coronavirus is species-specific, only affecting exposed cats. 

Humans are in no danger of catching, transmitting or experiencing symptoms of Feline Coronavirus!

But my cat has Feline Coronavirus, and then I started experiencing similar symptoms.

No, no, no! Don’t be that person blaming your cat for the take out you got last night or the expired dip you ate before bed. Humans are not susceptible to Feline Coronavirus!

Is Feline Coronavirus Serious?

Feline Coronavirus alone is not much to fret about; conversely, the mutation into Feline Infectious Peritonitis is concerning.

The problem is that most owners, shelters and breeders don’t know when a cat or kitten is susceptible to mutation. 

FIP is a perilous feline disease for which there is currently no cure. It only occurs in 5% of cats, but for that 5%, it is genuinely heartbreaking. Unfortunately, the mortality rate of Feline Infectious Peritonitis is close to 100%.

Feline Coronavirus Vaccine

Vaccine for Feline Coronavirus
The Feline Coronavirus Vaccine is a tricky one to nail down. Although there is a vaccination for FCoV/FIP, it is not generally recommended by the American Association of Feline Practitioners.

The vaccine may be available in some parts of the world, but not all. Ask a local vet for their opinion on the matter.

FIP Vaccination Schedule

Age Vaccination
16 weeksFIP Initial dose
20 weeksFIP Booster
AnnuallyFIP Booster

Immunization via injection or inoculation may seem futile, considering Feline Coronavirus in its enteric form often causes no or mild symptoms and will leave the cat naturally immunized.

While a vaccination to eliminate the risk of FIP in cats is the goal, simply injecting FCoV antibodies would adversely cause the mutation to begin in cats susceptible to mutation.

Testing for Feline Coronavirus

Testing for Feline Coronavirus
A stool sample can determine the diagnosis of Feline Coronavirus.

Although this form of testing only confirms the diagnosis of FCoV, it does not ensure whether or not a cat is susceptible to the often fatal Feline Infectious Peritonitis. 

Routine blood tests for Feline Coronavirus are not valuable for diagnosing FIP because they do not pick up the mutant gene or abnormality that causes the manifestation of the devastating disease.

Therefore the diagnosis of FIP is made from a positive FCoV result and evaluation of clinical signs.

Conclusion: Remember, the Mutation of Feline Coronavirus is Very Rare

So don’t worry too much without reason. Immunization of the mutation of Feline Coronavirus may not be possible at this point in time, but keeping up with annual vet visits and boosters are still the key to disease prevention in beloved pets.

In addition, simple things like healthy eating, hydration, and some good old fashioned love and attention from adoring pet parents can do more than one might think in averting illnesses and infection in cats.

Check out the blog for more detailed advice to help you take care of your beloved feline companion.