Here are some diseases that you should watch for and their symptoms.
Feline Infectious Peritonitis (FIP) is the disease most feared, and in fact, is the leading cause of death in cats. It is caused by a coronavirus infection and the worst is that the symptoms are very common with other ailments, so it's really hard to tell.
There is also Feline Immunodeficiency Virus (FIV) which is similar to HIV (human immunodeficiency virus). Like the human version, is a life long infection that moves slowly and can kill the cat.
Cats can also be infected with Feline Leukemia Virus (FeLV). FeLV is a retrovirus that causes terminal cancerous and noncancerous diseases. Fortunately, you can try using detergent and bleach, as well as warmth and drying to cure the virus. The virus is spread by saliva, tears, urine and feces of an infected cat. Unlike the other two diseases, it will not live that long in the environment and it is contagious only when the infected cat stays with another cat for a long period of time.
Worms are also another problem to cats and this is caused by a fungus infection that is spread by spores. Because it is self-limiting illness, you don't need to do anything to make it disappear. It will eventually go away, but it may take a few months.
If your cat is overweight, it probably already has feline diabetes. The symptoms of this disease include excessive urination and thirst plus noticeable weight gain or loss. Vets are not sure what causes this, but there have been some scientific studies that have shown a connection between pancreatic disease, hormonal imbalance and certain medications.
The symptoms of most of these diseases are very similar. These include diarrhea, vomiting, lameness in one leg lasting for longer than 5 days. Also decreased vision, excessive panting, a seizure, blood in the stool or urine, hair loss, and persistent coughing or gagging. To find the proper answer, your cat needs to see a vet to be tested.
Your veterinarian will sample blood, urine and feces. Any input from your observations will also help. When results of the tests are finalized, proper treatment can begin. Keep in mind that each case varies, and what works for one cat may not work for another.
Your cat can remain healthy if given constant attention. This can be done by feeding him high quality food and providing fresh water. In addition, your cat needs proper exercise, grooming, and make sure your pet stays indoors. And importantly, regular visits to the vet.