Coryza in cats

Coryza, the common cold, feline viral rhinotracheitis, or influenza… many names for the same entity. This syndrome affecting the upper respiratory tract is unfortunately not rare in cats.

What is the cause of coryza ?

Although this highly contagious condition usually affects the upper respiratory system, and is therefore frequently expressed by the presence of nasal discharge, sneezing, fever and reduced appetite, this is not always the case. Indeed, it all depends on the origin of the condition: there are actually several causes. Most of the time, coryza is of viral origin:

• Calicivirus is very often associated with gingivitis and/or stomatitis, with mouth ulcers and salivation;
• Herpes virus is very often associated with coughing and/or conjunctivitis, which may be complicated by a corneal ulcer.
• Polyarthritis – an inflammation of the joints – may also be present.

It is also possible that bacteria are involved, such as Bordetella bronchiseptica, Chlamydophila felis and Mycoplasma felis.

How is coryza transmitted ?

Coryza is only transmitted between cats. This is either through direct contact, via eye discharge or saliva, or indirect contact via sneezing – which can reach up to 1.3m! – or by eating. Rhinotracheitis usually affects young animals (between 2 and 12 weeks of age) that have not yet been vaccinated, cats living in groups, and immunocompromised cats – such as cats with FIV or leukemia. A large number of affected animals are considered to be healthy carriers, which means that they do not show any clinical signs.

Feline herpesvirus, like other viruses of the herpesvirus family (the human fever blister is also due to a herpesvirus, different from that of the cat), can become latent – dormant – in the lymph nodes. The animal is therefore still a carrier, but it does not excrete the virus during this time and shows no signs. In times of stress, fatigue, deficiencies, during gestation or after major surgery, for example, the virus can wake up.

The best way to prevent coryza in cats is through vaccination. The vaccine protects against herpesvirus, calicivirus and Chlamydia, and the first injection can be given from the age of 8 weeks.

How do I treat my cat ?

If your four-legged friend retains his energy and appetite despite the sneezing, there is no urgent need to consult a doctor. You can help him by regularly cleaning his nose with saline compresses and by using a suitable eye cleaner for the eye area. You can also increase the amount of wet food in his diet to make it easier to take and increase water intake. Inhalations are usually helpful: remember to use a cat-friendly mixture. Not all essential oil-based formulations are suitable.

However, if your cat seems weakened, is no longer eating or is showing signs of a corneal ulcer, make an appointment with your vet without delay. Depending on the symptoms and the suspected agent, the treatment may vary: oral or nebulised antibiotics, bronchial fluidizers, antivirals, anti-inflammatories, etc. If ocular signs are present, your vet will prescribe local treatments in gel or eye drops, such as antibiotics or antivirals. Your vet may also advise an eye lubricant, as tear production may be temporarily reduced due to the virus.

Your vet will probably want to know more about the agent that causes your pet’s high fever, in order to prescribe the most appropriate treatment. In this case, your vet will send a swab sample to the laboratory for PCR identification. Depending on your cat’s profile, your vet may also test your cat for feline leukemia or FIV. This test can be done in the clinic, after taking a small amount of blood.