Deltavirus /del′təvī′rəs/ , a genus of satellite viruses that require a helper hepatitis B virus for their replication. An individual consists of spherical virion 35-37 nanometers in diameter with an envelope derived from the helper virus surrounding a spherical core 18 nm in diameter; the genome consists of a single molecule of single-stranded, negative-sense, circular RNA (size 1.7 kb). It contains a single species, hepatitis D virus. See also hepatitis D.
