Dec 9, 2024
Cat flu, commonly known as feline upper respiratory infection, is a widespread condition that affects many cats worldwide. Similar to the common cold in humans, it primarily targets a cat's respiratory system, leading to symptoms like sneezing, nasal discharge, and eye issues.
This disease is generally not life-threatening in healthy adult cats. However, cat flu can be dangerous for kittens, old cats, and cats with weak immune systems.
What Causes Cat Flu?
Cat flu is a term for an upper respiratory infection that is usually caused by two viruses: feline herpesvirus and feline calicivirus. Additionally, cat flu can also be caused by bacterial infections. This makes cat flu more of a general term for infections involving a cat’s upper respiratory system.
Feline Herpesvirus
Feline herpesvirus, also known as FHV-1, is a highly contagious virus that targets a cat’s upper respiratory system. It primarily affects the eyes, nasal passages, and throat. Once infected, the virus can cause serious issues other than cat flu.
The virus causes multiple problems, such as corneal ulcers, conjunctivitis, and other eye problems in cats. Be sure to look out for your cats as the virus can spread from cat to another easily, especially in crowded areas.
Feline Calicivirus
Feline calicivirus is another major cause of cat flu, affecting the respiratory tract and oral health. The virus comes in multiple strains, with some causing mild symptoms and others leading to severe, systemic illness. These strains can also affect the joints and kidneys.
The virus will mostly stay on the lining of the cat’s mouth. After replicating, it can spread to other organs. This can cause sneezing, nasal discharge, fever, and drooling. In more severe cases, cats may experience joint pain or pneumonia.
FCV is remarkably resilient and capable of surviving in the environment for extended periods. This makes it easy to transmit through contaminated bowls, bedding, and toys, as well as through direct contact with infected cats.
Chlamydia felis
Chlamydia felis is a bacterial pathogen that primarily affects the eyes, causing conjunctivitis. Cats infected with C. felis often have red, swollen eyes with watery or thick discharge. It can also contribute to problems in the upper respiratory symptoms, gastrointestinal tract, and reproductive tract.
This bacterium spreads through direct contact with infected cats, as it can’t survive in the environment. Co-infections with viruses can worsen symptoms, making infections harder to treat.
Bordetella bronchiseptica
Although more commonly associated with kennel cough in dogs, Bordetella bronchiseptica can also infect cats, particularly in crowded settings such as shelters or catteries. This bacterium causes symptoms like coughing, nasal discharge, sneezing, and fever.
Bordetella is highly contagious and spreads through respiratory droplets. Cats can also contract it from infected dogs, making it an issue in households with cats and dogs.
How Do Cats Get the Flu?
Cat flu is highly contagious and can easily spread from one cat to another. Here’s how the cat flu spreads:
Direct Contact
Cats infected with the flu shed the virus or bacteria in their saliva, nasal discharge, and tears. When an infected cat sneezes or coughs, droplets containing the pathogens can spread to nearby cats. Direct contact is the most common way cat flu can spread from one cat to another.
Contaminated Objects
Transmission doesn’t stop at direct contact. Contaminated food and water bowls, bedding, toys, or even scratching posts can harbor the pathogens. If a healthy cat interacts with these items, they risk becoming infected.
Human Contact
Additionally, humans can act as carriers for pathogens. When a person or their belongings touch the cat, the virus or bacteria can easily be transmitted.
What are the Symptoms of Cat Flu?
Generally, cats experience the same symptoms humans do when they have the flu. Here are the most common symptoms of cat flu:
Respiratory Symptoms
One of the most noticeable signs of cat flu is through respiratory symptoms. Cats with flu often exhibit sneezing, coughing, nasal congestion, and nasal discharge. You might hear wheezing or see your cat breathing through their mouth if their nasal passages are severely blocked.
In more serious infections, symptoms can escalate to breathing difficulties, pneumonia, or severe dehydration. If untreated, these complications can be life-threatening.
Eye Issues
Eye-related symptoms are a hallmark of cat flu, especially with infections caused by feline herpesvirus or Chlamydia felis. Cats may develop conjunctivitis, which causes redness, swelling, and discharge from the eyes.
The discharge can be watery or thick, often making it difficult for the cat to open its eyes fully. In severe cases, untreated eye infections can lead to corneal ulcers or long-term damage.
Fever and Lethargy
Many cats with flu experience a fever, which can make them feel tired and less active. Lethargy is common, and your normally playful cat may spend more time resting or hiding. They may also appear less responsive to stimuli or avoid interaction altogether.
Loss of Appetite
Cats with flu often lose their appetite due to a combination of nasal congestion and oral discomfort. Feline calicivirus, in particular, can cause painful ulcers in the mouth and throat, making eating or drinking difficult. As a result, dehydration and weight loss are inevitable.
Oral Pain
Mouth ulcers caused by feline calicivirus often result in excessive drooling. Cats may also paw at their mouth or show signs of oral pain, such as avoiding hard food or refusing to eat altogether.
Behavioral Changes
Cats suffering from the flu may show subtle behavioral changes. Because of the stress and discomfort they experience, they’ll be grooming less and might seek to hide in solitude. Other cats might also become clingy and vocalize more.
Additionally, they might also lose interest in things that they love, such as playing and cuddling. The stress from cat flu will make them super uncomfortable.
How to Diagnose Cat Flu?
Cat flu can be easily diagnosed because of the clear symptoms it presents. Determining the cause of your cat’s flu will be the main thing to look for in order to proceed to the most appropriate treatment option. Here are the ways vets diagnose cat flu:
Veterinary Examination
When you take your cat to the clinic, the first step will be an extensive checkup. With your help, we’ll assess your cat’s overall condition, which will include their breathing, eyes, nose, and mouth. Our vets will need to ask for the symptoms you’ve noticed as well as any medical history.
Diagnostic Tests
To confirm our diagnosis and identify the virus or bacteria causing your cat’s flu, we may recommend certain tests:
Swabs
Samples from your cat’s eyes, nose, or throat can be collected using swabs. These samples are sent to a laboratory to test for the common causes of cat flu. Once the results are back, treatment for your cat’s flu will depend on what pathogen was identified from the sample.
PCR Testing
Polymerase chain reaction tests can detect the genes of viruses and bacteria. This test is particularly useful for pinpointing whether feline herpesvirus or feline calicivirus is the cause of the cat flu.
Blood Tests
In some cases, blood tests will be used to assess your cat’s overall health and check for any signs of systemic infection or inflammation.
X-rays
If your cat shows severe respiratory symptoms, such as difficulty breathing, we may take X-rays to check for pneumonia or other complications in the lungs.
How to Treat Cat Flu?
Treating cat flu focuses on alleviating symptoms, supporting your cat’s recovery, and preventing complications. Sadly, there are no specific treatments for the viruses. But with timely care, your cats can be treated for cat flu.
Medications for Cat Flu
Medications will be used to treat and relieve the symptoms cats with the flu face. Here are some of the common ones that will be used:
Antibiotics
Doxycycline is a popular antibiotic that is effective against Chlamydia felis and Bordetella bronchiseptica. It is often used for respiratory infections and conjunctivitis. Amoxicillin-clavulanate is also another antibiotic that is effective against a wide range of bacterial pathogens.
These antibiotics may be given as oral tablets or liquids, depending on the severity of the infection and your cat’s ability to tolerate the medication.
Eye Drops and Ointments
Additionally, we may also prescribe antibiotic eye drops or ointments to treat bacterial conjunctivitis and reduce eye discharge and swelling. If your cat’s eyes’ are irritated, we’ll use eye drops to lubricate the eyes to provide relief.
Other Medications
In addition to antibiotics, medications such as anti-inflammatory medicines can also be of good use when dealing with the symptoms. Other medicines tailored for each specific symptom will be prescribed when needed.
Supportive Care for Cat Flu
Cats will often lose their appetite, become dehydrated, and experience discomfort. To help them recover, using supportive care options along with the main treatment plan will be helpful.
Hydration
Dehydration is a common complication of cat flu, especially when cats stop drinking or lose fluids due to fever. Encourage drinking by providing fresh water at all times and placing multiple water bowls around the house. Wet food can also help strategically maintain hydration.
Nutrition
Offer soft, highly palatable food like tuna or chicken to help your cat eat. You can also throw in a few healthy treats to make them gain interest in eating.
Clearing Nasal Congestion
Nasal congestion makes breathing difficult and can suppress appetite. A simple home remedy can help. Do this by letting your cat sit in a steamy bathroom for a few minutes to loosen mucus and clear their nasal passages. Gently clean the nasal discharge with a soft, damp cloth.
Comfort
Provide a comfortable resting area for your cat with soft bedding. Give your cat time to rest and avoid making any noise in the process. Also, continue to stick to your cat’s routine. You should also keep your sick cat separated from other pets to prevent the flu from spreading.
The Importance of Vaccinating Against Cat Flu
Because the most common causes of cat flu are viruses, vaccination proves to be an important factor in preventing flu in cats. It protects your cats, reduces the severity of the illness, prevents the spread of cat flu, and is a very cost-effective solution.
Conclusion
Because cat flu is commonly caused by viruses, treatment might be tricky. The treatment process only helps manage the symptoms and kills bacteria. This is why preventing cat flu through vaccination is the most effective way to protect your cats.