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Symptoms of Feline Leukemia, What to Watch For

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In last week’s post we answered the question, What Is Feline Leukemia? Today we turn our attention to the symptoms of feline leukemia. Read on to learn how to look out for this disease, and how to better protect your cat.

Just what is Feline Leukemia (FeLV)?  And, what is the cause of this deadly cat disease?  These are good and important questions.  After all, before any real discussion about the Symptoms and Spread of Feline Leukemia can proceed, the cause and prevention of this lethal cat disease must be understood.

What Feline Leukemia Is

Feline Leukemia is a highly contagious, ubiquitous, and species-specific blood disease of cats.  While deadly to cats, FeLV does not infect other species―including humans―at least not yet. FeLV is a gammaretrovirus―which is more than a big scary word!  Basically, it means the virus can suppress the immune system and cause lymphomas in cats.

People and other non-cat animals won’t get this blood disease from infected cats.  In other words, you can’t catch FeLV.  Unlike the Covid-19 virus, FeLV has never been shown to jump to humans or other non-feline animal species.  Cats alone suffer this specific disease though other species, such as humans, do get their own variety of blood diseases. These can include various other types of Leukemia.  As a cat parent you and your non-cat pets are currently safe from FeLV.  However, your pet cats should get the FeLV vaccine for their protection since they may directly or passively catch the virus from another cat.

Cause of FeLV

Like I said above, FeLV is a contagious disease of cats caused by a virus that is spread from cat to cat by close contact.  The most probable spread results from saliva, bites, or scratches that happen during fighting, mating, or playing.  But, there may also be FeLV spread from residual contamination of grooming tools, food and water bowls, or other shared contact surfaces.

Symptoms of Feline Leukemia

Cats may not have symptoms of FeLV in the early stages, especially if they acquire it at a young age. But, they will get weaker and more symptomatic over time. This may take several months or years post-infection.  Not vaccinated and infected, the cat’s health will probably go downhill with frequent swings between apparent good health and sickness.

FeLV Symptoms to Be Aware Of:

  • Very contagious among cats
  • No interest in food
  • Weight loss
  • Rough haircoat
  • Swollen glands
  • Persistent fever
  • Constant diarrhea
  • Chronic eye infections
  • Pale gums
  • Severe tooth loss
  • Excessive saliva
  • Chronic skin infections
  • Nervous system disorders
  • Pregnancy abortions
  • Death within 3 years

Spread of Feline Leukemia

As you can see, the symptoms of FeLV are many.  The very important takeaway is that Feline Leukemia is a highly contagious, yet preventable cat disease.  Usually, but not always, FeLV infection is a death sentence to the cat.

Some unprotected cats do survive FeLV and some may not even show symptoms.  However, most will have symptoms and will probably die from it.  It’s important for cat owners to know that all non-vaccinated, infected cats will likely spread the virus to all other cats they come into passive or direct contact with.

Though they may be asymptomatic, all unvaccinated cats will carry and transmit the disease once they are infected.  Cats diagnosed with Feline Leukemia usually have a life expectancy of less than three years.  There will be more on that and FeLV prevention in the third and last article on this subject.

I hope this article on the symptoms of feline leukemia has been informative to all of you pet parents.  If you missed the first feline leukemia article you can read it here.

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