The symptoms of FeLV are often similar to those of advanced FIV, which is why the two are sometimes confused. Symptoms may include lethargy, poor appetite, weight loss, vomiting, diarrhea, oral inflammation, chronic eye problems, and pale mucous membranes. However, one of the biggest differences between the two viruses is that an FeLV+ cat will often exhibit these symptoms regularly throughout its life, but an FIV+ cat may remain asymptomatic for its entire life.
Interestingly enough, about 70% of cats exposed to FeLV are able to resist infection or eliminate the virus on their own. However, as described in our post The Ins & Outs of FIV, once a cat has been infected with FIV, the cat will always have it. A cat cannot fight it off and then develop an immunity, like with FeLV.
FeLV, however, is a different story. FeLV can be passed through biting like FIV, but it can also be passed through shared grooming, shared food/water bowls, and shared litter boxes. The chances of the virus being passed through these friendly activities is less likely than through biting, but the risk is still there.
Confusing these two viruses is one of the reasons that some may believe that FIV+ cats cannot safely live with FIV- cats.
Treatment of the two diseases is basically the same. There is no cure for either, but as long as an infected cat is kept indoors, given proper care and love, and is treated for any secondary illnesses, they may live a healthy life. However, 85% of cats who are persistently infected with FeLV will die within three years of diagnosis, whereas an FIV+ cat can live for several years without even showing signs of illness.
There is an FeLV vaccine, but like the FIV vaccine there are a few issues – the biggest being the risk of injection-site sarcomas. Also, the vaccine is not 100% effective at preventing infection. It is important to discuss the pros and cons of the vaccine with your vet before making a decision about whether or not to vaccinate.
If you have any questions about FIV, please do not hesitate to ask us. We are more than willing to help out in any way possible. If you would like to read more about FIV, we recommend visiting the Catwork website. It contains a wealth of information on the subject.
Also, we created this FIV awareness badge for anyone who may have an FIV+ kitty. Please take it if you would like to and display it however you see fit. Maybe if someone see that there are so many homes with FIV+ cats, they will think about making their home open to one as well.