Calicivirus Isolation From an outbreak of Vesicular Disease in California Pinnipeds
E. S. Berry1; J. E. Barlough1; D. E. Skilling1;
A. W. Smith1; N. A. Vedros2
A severe outbreak of vesicular disease was observed in pinnipeds at the
California Marine Mammal Center in 1984. Vesicular fluid collected from these animals was
examined by direct electron microscopy and found to contain calicivirus-like particles. Samples
of vesicular fluid inoculated into cell cultures (Vero cells, a primate cell line) produced
cytopathic effects; passaged cell culture material was found to contain calicivirus. The isolate
was cloned by 4 plaque-passages in Vero cells. Antibodies to this isolate, designated CSL-461,
were found in 24/29 California sea lion pups sampled on San Miguel Island, California, in
September 1984. Antibodies to CSL-461 have also been found in 2/69 bovine sera collected in
Oregon in late 1984. Currently serological and biochemical studies are being performed to
identify this new isolate, for comparison to previously isolated marine calicivirus
serotypes.