FeLV and FIV are viral diseases that affect your cat in a similar way.  Both viruses attack your cat's immune system and leave it susceptible to many secondary infections.

The FeLV (Feline Leukemia Virus) virus is typically spread when the saliva of an infected cat
comes into contact with another cat. This commonly occurs when cats lick and groom each other or share water and food bowls.  The virus can also be spread through urine and feces which occurs when cats share litter boxes.

The outcome of FeLV infection is variable.  Approximately 30% of infected cats recover completely and no longer carry the virus. Approximately 30% of infected cats become carriers of the virus. The remaining 30% of cats succumb to the disease.

The FeLV virus causes several conditions to occur in the cat. These include lymphoma (a type of cancer affecting white blood cells), anemia (too few red blood cells) immune deficiency and immune-mediated conditions.  FeLV infection is diagnosed using a simple blood test which identifies FeLV antigen.

There are no proven effective treatments for FeLV, although there is continuing research to find a cure or treatment for the disease.  It is important to treat the secondary bacterial and fungal infections and to provide supportive therapy when necessary.

FeLV infection can be prevented by eliminating or minimizing contact with FeLV infected cats and by vaccination with a FeLV vaccine.  It is recommended to test for FeLV infection prior to vaccination.

The FIV (Feline Immunodeficiency Virus) virus is shed in the saliva of infected cats and is spread through bite wounds occurring when cats fight.  For this reason, outdoor cats (especially intact males) or cats that come into contact with stray cats are the most likely to become infected.

FIV infection leads to destruction of T-lymphocytes (a white blood cell which is an important part of the immune system). This results in chronic and recurrent infections.  Infection is life-long and eventually fatal.  FIV infection is diagnosed using a simple blood test which detects antibodies to the virus.

FIV infection is incurable but asymptomatic cats may live for years before developing signs of the disease.  Sick cats often live for months with judicious use of antibiotics and supportive care.  There is no vaccine for FIV.  The only way to prevent infection is to prevent exposure.  Inside cats have little chance to be exposed to infected cats.  Neutering outdoor male cats decreases their chance of exposure since they are less likely to fight with other cats.

If your cat is infected with either FeLV or FIV it is important that you prevent their coming into contact with other non-infected cats, for example infected cats should not be allowed outdoors.

To this date, FeLV and FIV have only been found in domestic and wild cats.  There is no risk of you or your children or non-cat pets becoming infected with either virus.