Microscopic and Molecular Evidence of the First Elasmobranch Adomavirus, the Cause of Skin Disease in a Giant Guitarfish, Rhynchobatus djiddensis

Only eight families of double-stranded DNA (dsDNA) viruses are known to infect vertebrate animals. During an investigation of papillomatous skin disease in an elasmobranch species, the giant guitarfish ( Rhynchobatus djiddensis ), a novel virus, distinct from all known viral families in regard to particle size, morphology, genome organization, and helicase phylogeny was discovered. Large inclusion bodies containing 75-nm icosahedral viral...