An<unk>  is a virus that has ribonucleic acid <unk>  as its genetic material and does not replicate using a DNA intermediate.<unk> es belong to either Group III, Group IV or Group V of the Baltimore classification system of classifying viruses. Their nucleic acid is usually single-stranded<unk>  (ssRNA) but may be double-stranded<unk>  (dsRNA). Notable human pathogenic<unk> es include SARS, Influenza and Hepatitis C.
RNA virus
Aerobic organism
Helper dependent virus
Viral vector
Anaerobic organism
Parasitic worm
Gram-negative bacteria
Cancer bacteria