Angie Panczak
Savannah Super Cat
FIP is caused by a mutated version of Coronavirus, but research shows that the immune system of the cat can be key to development of the disease also...so the cats that fall ill may have some defect to their immune system. That is the genetic portion of this. So sometimes a cattery will have a litter where kittens get FIP and it might not just be exposure to the virus (as we know that most cats are exposed to Coronavirus and don't get ill) or a "hot" virus (as the FIP form is not shed in feces) but that there was a bad genetic combination and the kittens have some as-yet-undefined fault that made them more susceptible.
What is meant by 'hot Virus'?