Kittens can die from the disease, especially if they get pneumonia. Cats with respiratory disease have watery or sticky discharge from the nose and eyes, nose and mouth sores, inflamed eyes, and fever. Most respiratory diseases are caused by one of two viruses - feline rhinotracheitis virus or feline calicivirus. Rhinotracheitis tends to be more severe and can cause abortions in pregnant cats. Vaccination against these two viruses is usually given in a single dose.
Veterinarians can use either an injectable vaccine or one given as droplets in the cat's nose.
Vaccination helps prevent, not cure, disease. Vaccines contain viruses or bacteria that have been altered so they don't cause disease. When your cat is given a vaccine, its immune system produces special substances called antibodies that work against the viruses or bacteria that cause the disease. Later, if your pet is exposed to that disease, these antibodies quickly destroy the disease-causing agent. The protection provided by a vaccine gradually declines after a pet is vaccinated.