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Cat Encephalitis

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Encephalitis in cats is a rare but potentially life-threatening disease. It involves the inflammation of the brain and can sometimes be accompanied by the inflammation of the spinal cord (myelitis) and the inflammation of the meninges (meningitis).

What Causes Encephalitis in Cats?

There are a few different causes of encephalitis, which can each affect the severity of the condition in various ways. Many types of infections can cause encephalitis. Feline immunodeficiency syndrome (FIV), feline infectious peritonitis (FIP), and rabies are all types of viral infections that could lead to encephalitis. Bacterial, fungal, and parasitic infections could also be other types of causes, along with autoimmune diseases. In this case, the brain can attack itself, which leads to inflammation.

With encephalitis, some causes may also be idiopathic, meaning that the origin is unknown. No matter the cause of this condition, nearly any cat, no matter age or breed, could still be affected.

Symptoms of Encephalitis in Cats

Encephalitis symptoms can often appear spontaneously and progress rapidly. Because of this, it’s crucial that upon noticing any unusual behavior or physical changes in your feline friend, you take them to their veterinarian as soon as possible.

Symptoms to be aware of include,

  1. Fever
  2. Seizures
  3. Behavioral changes
  4. Head tilting
  5. Facial paralysis
  6. Decreased responsiveness
  7. Pupil abnormality
  8. Uncoordinated movements

The severity of these symptoms may alter as the condition progresses. However, if you observe any of these in your cat, begin taking note of them right away. There are many symptoms of encephalitis that can overlap with other health conditions. Being able to provide some additional information to your veterinarian about the changes your cat has been experiencing may help in the diagnosing process.

Diagnosing Encephalitis

In order to know if your cat actually has encephalitis, it will be necessary to take them to their veterinarian or animal clinic. Once there, you will need to provide your cat’s medical history (if it’s not already on records) and updates on the symptoms your cat has been experiencing.

After which, your cat will receive a complete examination, in addition to some physical and neurological tests. Some veterinarians may order an electroencephalography (EEG) in addition to urinalysis, bloodwork, and possibly a sample of your cat’s cerebrospinal fluid. Your veterinarian will utilize these tests to look for other possible causes of symptoms. For instance, seizures could be caused by epilepsy. Through some elimination, they will have a better idea about the root cause.

The results of these tests will depend on the cause of the encephalitis. For example, with some infections, your cat’s blood count will be abnormal, but their platelet numbers could decrease in other instances.

If your veterinarian wants to do further neurological testing, they may order an MRI (magnetic resonance imaging) or a CT (computerized tomography) scan. With more severe cases, when other efforts and tests return inconclusive, there is the option of doing a brain tissue sample. However, this is typically viewed as the last option because of the higher price and increased risk.

Is Encephalitis in Cats Contagious?

With feline encephalitis, people shouldn’t have to worry about the condition being contagious. However, depending on the cause of your cat’s encephalitis, you may want to double-check with your veterinarian if your cat should be separated from other cats or dogs in the house. There’s a slight chance that other pets could become affected.

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Encephalitis in Cats Treatment

As there are multiple underlying causes of encephalitis, there can also be many treatment options. However, as many veterinarians would agree, the first step of treatment is to decrease the swelling in your cat’s brain, followed up by managing and hopefully stopping any seizures. Once the serious symptoms are more under control, your veterinarian will most likely want to prescribe an antifungal, antiviral, anticonvulsant, or antibiotic. The exact medication will depend on what has caused your cat’s inflammation.

If tests conclude that there is no infectious disease as the root cause of this condition, your veterinarian may then prescribe a medication that will help suppress your cat’s immune system. The course of your cat’s treatment may look different than that of another cat with encephalitis, depending on the cause and how well they react to their treatment.


Although you may begin to see an improvement in your cat’s condition after just a few weeks of treatment, in some instances, treatment may need to continue for many months. For some felines, symptoms might reappear once the medication has been stopped. In this case, a second round of medicines may be necessary, or your cat might require a long-term treatment plan.

As part of your cat’s path to recovery, it is recommended that you take them for frequent check-ups with their veterinarian. During these appointments, your veterinarian will check how well treatment is working and make any alterations to your cat’s wellness plan as they deem necessary.

Encephalitis and Meningitis in Cats

While encephalitis involves inflammation of the brain, meningitis is when the outer membranes (called meninges) surrounding the brain, spinal cord, and central nervous system become inflamed. Although encephalitis and meningitis are two different health conditions, it is not unusual for them to appear simultaneously. When the two conditions occur at the same time, it is known as meningoencephalitis. This form of inflammation can be accompanied by more neurological signs such as depression, seizures, blindness, loss of consciousness, and seizures.

Like encephalitis, meningitis is a relatively rare disease, but it can still be a serious one. Although the condition may seem similar to encephalitis and a few of their symptoms might overlap, meningitis can present itself differently with a list of other signs. These could include a rigid neck, pain around the neck or back, decreased appetite, lethargy, fever, head tilting, and unbalanced walking.

Similar to encephalitis, if you notice meningitis symptoms occurring, it’s crucial that you take your cat to their veterinarian as soon as possible. Receiving a proper diagnosis and immediately beginning treatment can make all the difference for your feline friend. Each cat’s recovery can look different depending on how quickly they receive the medicine they need and how well they react to it. While some may return to their previously healthy selves post-treatment, others may live with side effects from this condition for the rest of their lives.

Encephalitis in cats is a serious condition that could be around for just a few weeks or months or cause life-long symptoms. Although not every cat may return to the health they had before encephalitis, with quick and proper treatment, many cases can be managed to help give your cat a normal, happy, and healthy life once again.

An ASPCA Pet Health Insurance plan can help you with eligible costs for covered conditions like surgery expenses for accidents and help provide peace of mind that your pet can receive the care they need. Check out our online resources to learn more about your insurance options and get a free quote today. The information presented in this article is for educational and informational purposes only and does not constitute or substitute for the advice of your veterinarian.

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