Experimental infections with feline caliciviruses (picornaviruses) in specific-pathogen-free kittens

Fifteen isolates of feline caliciviruses (picornaviruses) from Britain, the United States, and Australia have been compared with feline herpesvirus in their pathogenicity for SPF kittens in a gnotobiotic-type isolator system. Some isolates were apparently non-pathogenic, but the typical disease displayed transient fever, lingual ulcers, depressed appetite, and mild ocular and nasal discharge. Symptoms with the feline herpesvirus were more marked, but in no case was a disease comparable to that seen in the field produced. Pathologically at least 3 of the caliciviruses produced an interstitial pneumonia.