Infectious conjunctivitis, keratitis and kerato-conjunctivitis in cats Part 2: feline herpesvirus

Feline herpesvirus stands out as the pathogen most commonly responsible for respiratory and ocular abnormalities in cats. The virus is ubiquitous, has high morbidity, and becomes latent after acute infection, often reactivating during stress or immunosuppression. The viral infection may cause keratoconjunctivitis with corneal erosions/ulcers. The ocular disease occurs in four clinical forms: ophthalmia neonatorum in newborn kittens, acute infection in juveniles and young adults, recurrent infection due to reactivation of the virus after latency, and stromal keratitis which represents the chronic manifestation of the disease. While the diagnosis is relatively simple during the acute phase of the disease, it becomes challenging in the other cases. It is essential to modulate therapy based on the specific clinical form of the ocular disease. This review aims to comprehensively outline the etiology, pathogenesis, ophthalmic clinical signs, and diagnostic and therapeutic options of herpesvirus infection in cats.