Upper respiratory disease is a common condition seen in kittens and outdoor cats, but is also relatively common in cats that are kept primarily indoors. This is an infectious disease that can be caused by one or more agents. The most common primary causes are the Feline Herpes Virus (FHV) and Feline Calicivirus (FCV), but there can be other organisms that cause signs to occur. Secondary bacterial infections are also very common.

The typical signs are sneezing, ocular discharge, and fever. However, in some individuals other signs can develop, and can be quite severe. These include ulcers of the tongue and oral cavity, dehydration, crusting around the nose, very painful lesions of the eyes known as corneal ulcers, and in some individuals sore joints and lameness may result. In very rare cases, death has been reported. The majority of cats we see have mild to moderate signs, and respond well to basic medical and supportive care.

Most of the time we classify these individuals based on their clinical syndrome rather than arriving at a diagnosis based on the exact causative organism. For the individual cat, knowing the exact virus that is causing the signs is not usually needed because specific antiviral therapy is not used in the vast majority of cases. If there is a prolonged outbreak in a shelter, identifying the specific infectious agent may be pursued with a test known as a polymerase chain reaction. This is done via an outside laboratory.

Treatment may include systemic and topical (ocular) antibiotics to treat the opportunistic bacterial infections that occur, as well as supportive care in the form of providing proper nutrition, airway humidification, and a clean environment. In some cases if corneal ulceration is present, topical as well as systemic antiviral medication may be used. The type and duration of treatment will be tailored to the individual patient. It is also important to note that in a multi-cat household that affected individuals should be separated from the other cats. This condition is not felt to be contagious to dogs or people.

There is a vaccine for FHV and FCV however if the individual is vaccinated after exposure, there will be little benefit to vaccinate. FHV behaves the same way that the human herpesvirus does in that once an individual is infected he/she will be a lifelong carrier, and may develop signs of infection from time to time.