For some years veterinarians and researchers have noticed syndromes of immunodeficiency or weakness of the immune system in cats which could not be explained. The similarity between the syndrome in these cats and in humans suffering from AIDS was clear. Then, in 1986, veterinary researchers discovered a virus called the Feline Immunodeficiency Virus (FIV). The virus was related to, but not the same, as the human immunodeficiency Virus (HIV). Some 20 years before that, however, another virus called the Feline Leukaemia Virus (FeLV) was also discovered that may cause a similar AIDS-like syndrome in cats.
These two viruses, FIV and FeLV, are related and may thereforee have similar effects. They are slow viruses and it may typically be months or years after infection before they ultimately cause significant disease, although fatalities may also occur early in the course of infection. Infection is (almost) invariably fatal. Typically, various phases are recognised in the disease: There may be an acute phase after infection with fever and gland enlargement. That may be followed by an asymptomatic carrier stage (during which time no symptoms are seen, but the cat carries the virus and which may last months or years), and thereafter AIDS related illnesses and full-blown AIDS may set in. The viruses may also cause primary disease, or result in secondary disease by interference with the immune system. Cats infected with viruses may show any of the immunodeficiency syndromes such as:
- Chronic recurrent gum and mouth infections
- Chronic respiratory disease
- Skin and ear infections
- Weight loss
- Eye inflammation
- Intestinal infections
- Increased susceptibility to other common viruses
The viruses also cause illness directly, and various forms of cancer (especially lymphoma and lymphoid leukaemia), as well as bone marrow failure, anaemia, fading kittens, and kidney problems are associated with the infection.
How do we diagnose the infection? There are now well-developed and sensitive tests available to identify cats infected with the viruses and these can be performed by your veterinarian in the consulting room or by veterinary laboratories. Occasionally, especially in the early phase of infection, the test may be negative, and when there is doubt your veterinarian will advise a repeat test after some period. Some cats may also be infected with both viruses at the same time.
How are the viruses transmitted and can we prevent infection? FIV is not strictly contagious and transmission occurs primarily through bite wounds. It is thereforee possible for a cat that has FIV to live in a multiple cat household without being a risk to the other cats. FeLV, however, is contagious and transmission occurs through casual contact. An infected cat in a household would thereforee put other cats at risk of also contracting the infection. The viruses may also be transmitted to their offspring. To prevent infection with FIV is relatively straightforward: Prevent roaming and fighting with feral and other cats. Sterilisation is an effective method to assist in this. No vaccine is available to prevent FIV infection. FeLV prevention is more difficult. A vaccine is available, which can significantly decrease the risk. Vaccination is strongly recommended. It is also important to identify and remove carrier or infected cats from multicat households and to screen the viral status of new introductions.
There is currently no effective treatment available. Secondary syndromes such as bacterial infections are treated individually and symptomatically. Cancers can be removed or treated with chemotherapy in some instances. The viruses cannot be killed however, and infection will invariably be fatal once the AIDS syndrome appears. Resolution of one secondary infection is often followed by another. Prevention is thereforee most important and your veterinarian will be able to advise you specific to your circumstances. It should be remembered though that is not necessary to put all infected cats to sleep. As long as an infected cat is living a quality life and secondary problems are controlled, and the cat is not a threat to others, it may live a long time. Importantly, cats with AIDS do not infect humans and pose no threat to the health of its human family.Leave a reply →