Feline viral rhinotracheitis due to herpesvirus and calicivirus
What is feline viral rhinotracheitis?
In the case of herpesvirus, replication occurs in the nasal, tracheal and conjunctival mucosae. Besides these locations, calicivirus can also replicate in the pulmonary or oral mucosae, which explains the differences in their associated clinical signs.
Latent stage of feline rhinotracheitis
In addition to the acute clinical signs, feline rhinotracheitis can follow a chronic course, so the cat becomes a chronic carrier. The infection can also be reactivated if the animal is subject to certain stresses (disease, surgery).
In the specific case of calicivirus, it is constantly eliminated via the oropharynx, spreading the infection to other cats.
Clinical signs of feline rhinotracheitis
Feline rhinotracheitis can occur at any age, but it predominantly affects younger cats. Herpesvirus causes signs for 2–4 weeks, while calicivirus lasts for 1–2 weeks.
The main clinical signs are sneezing, conjunctivitis, blepharospasm, hypersalivation and cough. Herpesvirus infection can lead to ulcerative keratitis, whereas calicivirus causes pneumonia and ulcerative stomatitis on the tongue and palate. Both may be involved in chronic lymphoplasmacytic gingivitis stomatitis complex.
If there is a large amount of secretion in the airways, the patient may suffer dyspnoea due to obstruction.
Prognosis for feline rhinotracheitis
This depends on the cat’s baseline status. The prognosis is usually good, although there may be serious complications in malnourished or very weak kittens.
Treatment of feline rhinotracheitis
There is no curative treatment for feline viral rhinotracheitis, rather just symptomatic and supportive measures. Broad-spectrum antibiotics, such as amoxicillin, may be used to prevent or treat secondary bacterial infections.
In case of shock, fluid replacement therapy should be administered, together with nutritional support for small kittens.
Antibiotic eye drops should be used to treat any incidents of purulent conjunctivitis.
Keep the airways clear using saline drops or decongestants to avoid dyspnoea.
Corticosteroids are the best treatment if lymphoplasmacytic gingivitis stomatitis develops in chronic calicivirus carriers.
Kittens can be vaccinated after week 8 or 9, repeating the dose after 4 weeks and every year thereafter. Bear in mind that even after vaccination, a cat may still manifest mild clinical signs following exposure to calicivirus due to the different strains of the virus.